I've recently bought a set of HSS turning tools from Grizzly (picture below) and was wondering if anyone would be so kind to show me how they're used properly. Up into this point I've used the really cheap carbide tools from HF. These new tools have a little bit of a different design to them. I've found diagrams showing how the tools are should be used, but couldn't find anything on these.

Thank you
Chris

Here are a some pictures of what I'm getting

Material
- 6061 Aluminum
- 3.7" diameter
- 6" length

Grizzly 3/8 HSS Turning Tool ( I think this is the off set left hand tool, but not sure)


Lathe Settings

RPM's - 1000
Gear Box set to Lever 9 - 0.005" (A 28T gear, B 60T gear, C 120T gear)
Taking cuts of - 0.11" (3mm) per pass





My question is why am I getting such a deep grove ?

I'm still learning be gentle... :)

Anyone??

I have the same set that you do and looking at the picture that shows the tools I would use the one on the lower left. I use this tool and I dont have a powerful lathe at all but I can take about 1mm off a side cutting steel

I have the same set and get pretty good cuts on everything but the cut off tool.

You didn't mention what type of lathe you have. But I know I won't take cuts of .11" of at a time. Maybe .020 to .030 off onr side but that is about it. I would back the cuts off and try that unless your size was a typo.


I run my lathe around 1000 and below for speed. I am using a 9x21 lathe from Grizzly if that helps at all.

Sorry about that, I'm running a standard 9 x 20 lathe.

I'm using the second to the upper right tool, which I believe is a left hand offset tool, but I'm not 110% sure. I found a few things on the internet, but not much for running a 9 x 20 lathe ( hell I'm still trying to figure out the clutch on this thing ). I found a site that gives examples of how to determine the RPM's to use. Here's what I got


For 6061 T6 Aluminum with HSS turning tools, it says to use 500 - 600 and other sites recommend lower speeds such as 175 - 250. I'm a little lost on this one. :confused:

500 CS x 4
------- = 540rpms
3.7 D


Is this right??






I've kind of brushed the surface with the clutch on my lathe, but really didn't understand it. Here's my question

1. When the clutch is engaged (on), does that mean that the piece of rubber inside is pushing on the thin little rpm belt?

2. After starting the lathe and I'm ready to start cutting, do I leave the clutch engaged (rubber piece pushing on the belt) or away from the belt?

First off the tool you are using appears to be a facing tool but I could be wrong, The pattern in the first part of your post indicates which each is used for, typicaly a LH turing tool is all you will be using besides a facing tool on the conventional tool post, I will repost when I get home so I can look at you pictures a little better they don't come through well here.
As for cutting speed on the lathe with HSS bits I use a very simple rule and it works well,

4 times the cutting speed divided by the diameter, this also works for drills and mills wereas the mills/drills are the diameter for the speed, but not the feed.
I use for the most part unless I really know for sure what the speed is I use


4*CS/D
Alum/wood 200
steel 100
cast iron/bronze 150
brass 200
alloy steel and plain steel to from 1040(shafting) 50 or less
These are just guides the machinerys handbook has all the speeds.
With the case of carbide dry I do normally double speed and feed if possible, I don't use coolant often but when I do I go even faster, but no light cuts.
I go to the next slowest speed if I don't have one within a few rpms, as I face I try and run the speed up some(I have a DC motor now), as the diameter is decreasing resulting in higher rpms.
As for the clutch, you should. start the motor, engage the clutch, cut, you can either leave the clutch in while shutting off the motor, or disengage it first. My lathe(g4000 9x20) will not even spin with the clutch fully disengaged, please note there are a couple of operations that you may need to leave the clutch engaged esp metric threading(refer to manual) and only stop the motor. You can start the motor with clutch engaged but its hard on the motor and belts/gears.

I will try and help with the bits when I get home.


chris

Thank you!! Yes any tips, help would be greatly appreciated.


For 6061 you use a cutting speed of 200?


I notice when I move the carriage by hand slowly toward the chuck, at 600 rpms I get a nice finish. Now when I put it on auto feed, it comes out very groovy and not polish looking at all.


1. When engaged does that mean the clutch lever is toward me or away
- On - rubber pushing on the belt?
- Off - rubber off of the belt?

Basically which way is on and which way is off?

(The I'm using is the 9 x 20 Harbor Freight.)




"I have a DC motor now"

So you made the upgraded, did you do it yourself?




.

I would say that for the answer to one of your questions as to why you are getting the large grooves or rough surface finish is because there is a very small, if any radius ground into the nose of that tool you are using. If you are using a 5 thou per revolution feed than you need to have at leat 5 thou of the tip touching the work to give a smooth finish. I would grind a small radius of maybe .03" You can just use a honing stone to do this. Hope this helps.

chris.

Thank you!! Yes any tips, help would be greatly appreciated.


For 6061 you use a cutting speed of 200?


I notice when I move the carriage by hand slowly toward the chuck, at 600 rpms I get a nice finish. Now when I put it on auto feed, it comes out very groovy and not polish looking at all.


1. When engaged does that mean the clutch lever is toward me or away
- On - rubber pushing on the belt?
- Off - rubber off of the belt?

Basically which way is on and which way is off?

(The I'm using is the 9 x 20 Harbor Freight.)




"I have a DC motor now"

So you made the upgraded, did you do it yourself?




.

I got a better look at your pics, first things you need to do is make yourself a new compound rest mounting I think you maybe even be able to buy them through LMS now. That will make big difference, Second you need bring your tool into the post as close a possible the more ridgid the better, the chip breaker on the tool you are using indicates that you are using a facing and not a turning tool(its odd either way), lookin down onto the tool you should have a narrow steep left shoulder and broader shallower right the chip breaker should be near parallel to the work piece, although it may not have one at all. Your speed was too fast, and your are heat treating your tool tip which indicates you are rubing more then cutting, you may need to regrind the tool gently and keep it cool untill you are past that the heat treatment. Your grooving indicates that your feed is to aggresive, which means your tool isnt right/ bad angle/or sharp, I would expect that kind of find finish on a piece of 1045 shaft steel.
Also you have to remember if you are not using coolant that your tip will expand as it heats so agresive cuts should be avoided untill you have a good base cut, with a rough cut like that you will hit high spots creating even more heat.
I use a CS of 200 for most of the alum I do(i do mostly sand cast with some bar stock), typically I don't know for sure what the material is so I play it safe which seems to work well for me, its not a die hard rule, if I have finish problems which I often do I typically start to change the speed both up and down and see if it matters. Tool angle is critical with HSS, its not as forgiving as carbide in that right, also making sure you are on center, and of course sharp.
As for when you have the autofeed engaged(and not the screw cutting) that entirely depends upon your feed rate per revolution typically the slower you go the better the finish. Also with a finishing tool, you dish out the tip more then a roughing tool, I don't concern myself with finish on any alum I do, but cast iron I do, there I provide a very braod radius on the tip maybe near half of the tool bit but that is a different animal. So I can't help you much with fine finish on alum I just use a regular turning tool. Also how are are your chips breaking off? you might need to touch up the tool with some grinding wheel on the top to provide better chip clearance.

I suspect there is a problem with your clutch, can you provide a pic? with the lever towards you the clutch is disengaged, with it away the clutch is engaged. There is not any question when its in and when its out, mine stops and does not turn, as it should. The grizzly manual is decent try downloading that and see if gives a clearer picture, I would have to actually look at mine to determine which way the wheels bind up, if memory serves the belt is engaged from the bottom but don't hold it to me. Sorry I have not made it home yet to look, I had to babysit a friends forklift today.

Variable speed yes and no, the lathe I have at work which is a piece of scrap iron with a chuck, has a variable speed motor. My 9x20(same lathe as yours) is still stock but I do have the motor and control(90 VDC 1 HP) to put on, when I get some time I will it should be straigh forward as the motors are nearly the same size maybe a mounting or belt issue, if its not possible with the DC I have a metric 3 phase I will through on instead which is the same frame size(DC would be more fitting for this application). At this point use the machine untill you are comfortable then worry about upgrading, I have not used mine at home all that much( I got it third hand about 3 months ago) I currently use my shaper more then anything, so I have be careful about my HSS tool statements as they are ground different, I still refer to drawings when I have to grind new tools esp the lathe.

Chris

"I got a better look at your pics, first things you need to do is make yourself a new compound rest mounting I think you maybe even be able to buy them through LMS now."



Yes I completely agree. Here are a few pics that show exactly why I would need one. I can't understand why they would sell the machine this way. Only 2 hex bolts to hold it down, what a crock of sh*t. :(





"Second you need bring your tool into the post as close a possible the more ridgid the better, the chip breaker on the tool you are using indicates that you are using a facing and not a turning tool(its odd either way), lookin down onto the tool you should have a narrow steep left shoulder and broader shallower right the chip breaker should be near parallel to the work piece, although it may not have one at all. "



Yes that's what I have been reading. What if it can't reach, like when parting. Speaking of which my parting tool isn't working to great, well not really working at all. In the pictures below, you'll see a really chopping surface. I'm guessing it's the compound rest that I need to upgraded.

BTW I'm only seeing the 7 x 10 compound rest, not 9 x 20 over at LMS. I really don't have any time right now to make a Compound Rest as I have a critical deadline for the products I sell. However I might have to make some room for it, I can't have a finish that looks like this. Do you know of any other stores that sell any?

It's too bad that know didn't upload there Gcode file for a micro/mini CNC mill, but that would be to easy.:)




"As for when you have the autofeed engaged(and not the screw cutting) that entirely depends upon your feed rate per revolution typically the slower you go the better the finish. Also with a finishing tool, you dish out the tip more then a roughing tool, I don't concern myself with finish on any alum I do, but cast iron I do, there I provide a very braod radius on the tip maybe near half of the tool bit but that is a different animal. So I can't help you much with fine finish on alum I just use a regular turning tool. Also how are are your chips breaking off? you might need to touch up the tool with some grinding wheel on the top to provide better chip clearance. "




I read all night after I posted, and found that my speed was to high, and my feed was to fast. I didn't know that if you have a feed of .005" the tool needs to be in at the same distance. Very helpful, thank you!!!

I've read on finishing tools, looks like a really round edge (almost ballnose). I have a blank, so maybe I'll try to make one.


"Also how are are your chips breaking off?"


Well with the parting tool, they break off into little 2mm - 3mm chips, but it chatters like hell as I move in. With the facing and turning tool, long spirals, not chips.




"I suspect there is a problem with your clutch, can you provide a pic? with the lever towards you the clutch is disengaged, with it away the clutch is engaged. There is not any question when its in and when its out, mine stops and does not turn, as it should. The grizzly manual is decent try downloading that and see if gives a clearer picture, I would have to actually look at mine to determine which way the wheels bind up, if memory serves the belt is engaged from the bottom but don't hold it to me. Sorry I have not made it home yet to look, I had to babysit a friends forklift today."


Yes, below. In the one picture below you'll see the clutch disengaged, is the belt suppose to be that loose? I'm turing the material at 600 rpms, but with the clutch engaged. Now when I have it at 1000rpms, no slack at all. In the picture I'm pushing on the belt with my finger to tighten the slack, I'm pushing in about 2 inches or so.





"Variable speed yes and no, the lathe I have at work which is a piece of scrap iron with a chuck, has a variable speed motor. My 9x20(same lathe as yours) is still stock but I do have the motor and control(90 VDC 1 HP) to put on, when I get some time I will it should be straigh forward as the motors are nearly the same size maybe a mounting or belt issue, if its not possible with the DC I have a metric 3 phase I will through on instead which is the same frame size(DC would be more fitting for this application). At this point use the machine untill you are comfortable then worry about upgrading, I have not used mine at home all that much( I got it third hand about 3 months ago) I currently use my shaper more then anything, so I have be careful about my HSS tool statements as they are ground different, I still refer to drawings when I have to grind new tools esp the lathe. "


Keep me updated on this, I'm very interested!!!!:cheers:

I think your problem comes from lack of rigidity. basically your tool is bouncing off the work peice.

1. check your spindle bearings and make sure they are tight. (my 9x20 was loose from the factory.) you want the head to be really warm to the touch when running about 1000 RPM. you may want to pull the spindle out and lube the bearings prior to this.

2. i found the my compound was flexing. buy a quick change tool post with a larger diameter shank down the center. the stock one i think is around 8 mm. i currently use a 13 mm post down the center of my quick change tool post.

3. add a larger diameter handwheel to the cross slide feed. you can replace the lead screw as well but i noticed the largest difference with the larger hand wheel and tightening the gibs.

4. get some carbide tooling. do not get the brazed carbide get the inserts. there are inserts specially designed for aluminum and they are well worth the money.

5. after the mods above i can take .150 per pass when turning. thats about .300 of mterial removed from the diameter. (i did upgrade to a 3hp motor and a vfd for my lathe.)

I would first recomend going through your 9x20 and getting to know it very well. These machines need some attention in order to work anywhere near the machines physical limits. My 9x20 is heavily modified but it's still a 9x20 import.
I hardly ever use HSS bits anymore unless I need to form cut something or need a special bit.
As mentioned, the stock 9x compound clamp is a bad joke. And 3.7" Diameter turning is going to show you it's weakness.
Upgrade it ASAP.

Grizzly sells the Glanze carbide tool set. They work real well on this lathe.
Here is a pic of my 9x20 under powerfeed hogging 1/8" DOC( 1/4" off the diameter in a single pass) with a Glanze bit and CCMT insert on 6061.
http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/7xcompoundconversion014.jpg
http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/7xcompoundconversion020.jpg

Here is my photobucket of various 9x20 mods I have done. I have done some pretty neat things to this lathe.
http://s109.photobucket.com/albums/n48/S_J_H/9x20%20mods/?start=all

Double checked the lathe, the rubber wheel goes into the belt when engaged(dah) but that relieves the spring tension. So when the lathe is in neutral the spring is stretched.

When parting(the hardest and most dangerous normal operation) I give this advice, mount your tool on the back side and up side down then draw it into the piece from the rear, you will still get chatter esp with that tool post. Its almost worth either making or buying a new tool post if you do alot of cutting off. I goto about 90% of the way then stop the lathe and take a couple hits with a hack saw. Also make sure there is a small amount of side relief on the tool, a tool which is flush with the sides of the cut will rub an make alot of noise, again this is the most dangerous operation so be careful and make sure things are as rigid as you can get and expect a problem, being caught off guard can really hurt. Although there is nothing wrong with carbide, it still pays to understand how HSS works, this in turn will make using carbide that much easier. The other thing is that the HSS is flexible because you can grind without special equipment. Just today I ground JT33(about 1.5 degrees) taper on the end of 3/8 piece of HSS this in turn was mounted to my drill press table set at 90 degrees to clean up a bent noise on the spindle, I feed it by hand and spun it by hand. I took a TIR of .010 down to .001 or less. Never would have been able to do that with carbide esp not by hand.
chris

S_J_H sweet jesus is that a cnc machine you are running? what is that like 120 thou on one pass.

WOW you've been busy!!! Well I've found a site that sells a compound rest already made for only $40.00 bucks and anodize black, what do you guys think?

http://www.peck-polymers.com/store/Category.asp?Cguid=%7B510B48C6-9795-4824-AE8E-A5350E6A7232%7D&Category=LatheUpgrades%3AChineseMachines


OR



Should I just make one out of 1/2" steel





"Grizzly sells the Glanze carbide tool set."

Is this the set?

http://www.grizzly.com/products/G5640

S_J_H sweet jesus is that a cnc machine you are running? what is that like 120 thou on one pass.

That is my Grizzly 9x20 manual lathe. It's .125" deep in one pass :)
I normally take lighter cuts as even though the lathe can handle it, it's sort of rough on the machine.

This is the Glanze set- http://www.grizzly.com/products/h5680

Steve

Guys thank you for the help and advice.



------------------
$130.00 bucks for tools is a little out of my range right now, but they do look good!! What's the tool life on the inserts?




I'm just a little precautions on cutting raw steel with this setup, I've never cut anything this hard just yet. Hell maybe I'll try to make this thing tomorrow and stop being lazy!!!

BTW I'm only seeing the 7 x 10 compound rest, not 9 x 20 over at LMS. I really don't have any time right now to make a Compound Rest as I have a critical deadline for the products I sell. However I might have to make some room for it, I can't have a finish that looks like this. Do you know of any other stores that sell any?


http://www.littlemachineshop.com/products/product_view.php?ProductID=3027&category=

Well I've started on making one of my own, but if it doesn't work out I'll definitely buy this! Thank you for the link.

That is my Grizzly 9x20 manual lathe. It's .125" deep in one pass :)
I normally take lighter cuts as even though the lathe can handle it, it's sort of rough on the machine.

This is the Glanze set- http://www.grizzly.com/products/h5680

Steve

Thats crazy, even better I have those tools I got them with my lathe from the last owner, I have not used them yet but I think I will instead of the crummy cemented bits that were with it also. After I get a chance to got through it and fix a few more things.

chris

WOW you've been busy!!! Well I've found a site that sells a compound rest already made for only $40.00 bucks and anodize black, what do you guys think?

http://www.peck-polymers.com/store/Category.asp?Cguid=%7B510B48C6-9795-4824-AE8E-A5350E6A7232%7D&Category=LatheUpgrades%3AChineseMachines

OR

Should I just make one out of 1/2" steel


I made one like that and wasn't happy with it. So I made a heavier one out of cast iron. You can see it on my website. Even then I didn't get really good cuts until I adjusted my spindle bearings.

Alan

"spindle bearings"


Hmmmm, any guides showing how to?

Ok complete! Now I did fine up until the drilling holes part, two were a little off, but hell saved me $40.00 bucks. Here are a few pics of the part being made. Enjoy :)





Now if you look at the last couple of pics, this goes out to anyone trying this with very little experience. I definitely learned my lesson this time. I had a spiral piece of steel catch around my facing tool. I then tried to pull them off while the machine was still running with my fingers. It almost feels like the shredded steel has fingers, and yes they do grab you. Anyway the spiral piece of steel that was caught up on my tool, then caught my fingers and pulled me into the chuck almost severing my fingers. Aluminum is very forgiving, but steel is no joke.

DON'T GRAB ANY DEBRIS COMING OFF THE WORK PIECE UNTIL THE MACHINE HAS COME TO A COMPLETE STOP.

Hi, Geezus wept,words fail me, you are paying the price for messing about with a dangerous piece of machinery, if you had the sense to get some tuition before you switched the machine on you would know that anything that rotates, slides, vibrates, or just plain moves under power is a lethal cocktail that to the uninitiated is tantamount to a death wish.
To all those who mess about with machinery, without any form of training, count your fingers before you start, and if your a little short digitally at the end of the session, I told you so, but if they're still all there, count your blessings, you're living on borrowed time.
Ian.

Your pics show a dead center in the tailstock, and a VERY shallow center drill for the size of the stock you are using.

I suspect that if you just invest in a set of center drills of assorted sizes and also in a live center for your tailstock, you will solve all of your chatter and cut quality problems.

(btw, I also could detect no trace of lubricant at the dead center in your photos. Have to lube when using a dead center, with good high temp grease, and then make sure you keep your center adjusted during cutting)



Tiger

DON'T GRAB ANY DEBRIS COMING OFF THE WORK PIECE UNTIL THE MACHINE HAS COME TO A COMPLETE STOP

And DON'T grab any debrees with your hand, even with the machine stopped...stringers are sharp and will cut you, it won't even hurt their feelings. keep a small brush handy or pliers or something.

chris

I'd love to take classes, but with my business I work from 8 - 11 Mon. - Fri. If they had weekend classes, I'd probably go. I was hoping with my schedule that maybe someone here could help me or give me any advice... :)


I will say that getting the hex bolts ground perfectly to a T shape is a pain in the as* Soon to post a few pics. :)

Well since you are not familiar with some of the ground rules here it goes.
Anyone please feel free to add I am sure I am assuming things out of habit.

#1 Safety Glasses, I frequently break the gaurd has been removed for clarity sub rule(aka table saw). They should be worn at all times, that way you get used to them. I often see complaints at work about wearing them for odd operations, people who don't wear glasses esp this is true, if they would just leave them on longer they would get used to the effect of having them on.

#2 Treat all machines as they are engergized, many in fact are often considered engergized in the eyes of the goverment even if they are not plugged in as they often have springs, air, or gravity to work them. Although it would be a little over the edge in a home shop, LOTO (lock out tag out) should be understood, things like un plugging a wood router when changing bits, or using a disconnect on a mill/drll when changing bits. Its easy to bump switchs and hard to sew back on digits. I also have gotten into the habit of now including a 3 wire setup on machines which I need to rewire for what ever reason in my house. Loss of power results in loss of the control and the machine will not run untill restarted.

#3 Never grab a machine tool which is running, moving, traversing, indexing, or cutting. That part is easy, but included in that is too not grab chips untill you are stopped(and then with a hook or suitable tool), I will precluded one operation later. Also don't try and fix a part which has come jammed, disjarred, spun, or snapped. Push the stop button control the situation, as a shop teacher pointed out to me so easily it only takes 4 seconds to stop a drill press from high speed, (holding up his hand with four digits my favorite finger missing) and a fraction of a second to stop it with you finger. That point was well taken.

#3 Do not wear gloves, loose cltohing, shorts, tank tops, jewelry, watches, and keep hair above your shoulder tied back. Don't wear contact lenses around anyone welding, cutting, or otherwise using a welder. Beauty is for end product of your machine not for your body, clothes, and hair.

#4 If you are unsure of a particalar operation, look it up, ask someone, or call the manufacturer were applicable. A person was killed about a decade ago at the illinois railway muesum, he was cutting piston rings for a steam engine, had he done one simple thing in his setup the ring would have not come dislodged and cut his head nearly off.

#5 Never under any circumstances, operate a machine tool while by yourself, if there is not someone in ear shot of you, then you need to either have someone check on you occasionally or not operate it at all. Even the smallest machien tool can become deadly, ask anyone who has broken a small drill bit which has become lodged into they're body in some way shap or form, size can be decieving small machines spin fast. Often with a big machine you can stand out of the way while its working, small ones almost always need attention. If you accidently breakoff your finger tip while running a lathe, who is going to drive you to the hospital, besides you will have to hold your finger. My grandfather also a machine repair man got his right hand stuck in a press on a saturday while shut down, he was lucky there was atleast 2 other people in the plant at the time, he recovered most of his hand, the other person reached in and got 3 of his fingers back, had they not been there he would most likey have been dead by the time they found him. He lost his 2 middle fingers but we still had him, also he could not back the press of himself, once they got him free he fainted fromt he pain.

#6 Don't stick your hands were they don't belong, mom alwasy said don't stick your had in that hole. Belts, chains, crossheads, and shafts don't stop quickly, you may think you are faster then they are rest assurd you are not.
Driling a hole through a piece which is blind requires special care, when clearing chips use a brush or hook, grab it lightly, should it beocme entangled in the drill realease it. Also when drilling a hole, when its not possible to clamp the part down, make sure its held in such a way that should the part start to spin that it contacts the column, or is held to pieces which will.

I am sure I forgot some of the finer points.

chris

Well put in2, I weep for some of the well meaning blokes that just want to work, but haven't a clue when it comes to self preservation.
Cold steel, never a truer word spoken in hushed tones.
If I had a cent for the number of times I've seen people working on a simple drill press, and holding the job with one hand while leaning on the handle with the other, and that isn't counting the fact that they wouldn't think of wearing eye protection of any sort as well.
You get older as you get wiser, if you just take the time to learn the rules.
Ian.

Thanks guys for the advice. :) Sometimes the simplest mistake can be very costly, so I've slowed down a little and started reading more (not much on the internet from what I've found). I know sticking my hand in grabbing the spiral pieces of steel was a very stupid thing to do. I'm the kind of guy that's always safety first, but this time I just wasn't thinking. It was a fast reaction, that could of cost me dearly, but I'm determine to learn!

So I've started to make a plexiglas don't touch grad, that will come over the whole machine just clearing the carriage.



Now I understand most of the basic, I'm just a little confused on these grizzly tools and how they're properly used...


I've had success with the clamp, finally! I had to shave another .20 off the bottom, fits like a glove. I've noticed a big difference in the finish, but I'm still getting that choppy noise and finish when using the parting tool only??? :devious:

I think the problem is that my parting tool isn't high enough when cutting causing it to crash. There's also alot of vibrating along with noise when using this tool. So for a quick fix I'm just going to use a reciprocal saw to part my work for now.

when ever i part something off i use one of the slowest speeds and a lot of wd40.

make sure that your parting tool is aligned exactly on center with your spindle, an easy way to do this is to line the tip of the parting tool up to the dead center in your tailstock.

chris

"when ever i part something off i use one of the slowest speeds and a lot of wd40."


I was watching a utube video on parting with a lathe. The operator parted to work piece very easy, not like mine (and the video wasn't speed up). However he might have been using a much better lathe. :( I'll give it a try and see what happens. Thank you

"make sure that your parting tool is aligned exactly on center with your spindle, an easy way to do this is to line the tip of the parting tool up to the dead center in your tailstock."


Yes I've tried this last night after I posted, seems to be inline. I even tried a little test. I faced a part to see if it was inline, no little nub in the center, it cut right thru no problem. I then checked to see if the chuck and tailstock were inline, yes 100 %.

"when ever i part something off i use one of the slowest speeds and a lot of wd40."


I was watching a utube video on parting with a lathe. The operator parted to work piece very easy, not like mine (and the video wasn't speed up). However he might have been using a much better lathe. :( I'll give it a try and see what happens. Thank you

well what type of lathe was it? was it a cnc lathe? what was the material?

i always listen very closely when i part, when i start to hear the tool grab i quickly try to pull it out, sometimes it happens so fast that the tool gets jammed under the part and i have to stop the lathe, i make sure the belt is a little loose so that it can slip if it needs to. i have a crappy parting tool holder that doesnt hold it perfectly straight so thta is mostly my problem.

Ian, and others have also stated that its a good idea esp on older lathes to mount the toolholder upside down and on the back of the crosslide. I always thought that was standard practice myself untill real recently but I never do alot of parting on my lathe.

chris

SJH


On your lathe, did you need to make any mods for the phase 2 tool post (lager center bolt or anything at all)?

http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/7xcompoundconversion023.jpg







I'm really wanting to go all the way now that I've seen what I can do. The tool post is first on my list, and I'm really thinking about the insert bits too, but they're a little expensive.


1. QCTP

http://www.littlemachineshop.com/products/product_view.php?ProductID=2271&category=-139540609



2. Turning bits (LMS or Grizzly)


What's the difference between these sets?

Little Machine Shop

http://www.littlemachineshop.com/products/product_view.php?ProductID=1679&category=1208242246

OR



Grizzly

http://www.grizzly.com/products/H5680

http://www.grizzly.com/products/H5682


It sucks that I just bought the Grizzly HSS set for $50.00 with shipping, when I could have put that toward something better. :(

Hey twocic, now that's a nice lathe you've got, I can see one of your problems straight way, and this is common to practically ALL lathes.
The top slide or compound slide is so far up in the air, by nature of it's design, that when the parting tool is applied to the work it exerts a leverage on the tool post tool holder, and in addition, when a QCTP is being used, the parting tool is now unsupported beneath it, and so you are virtually out on a limb of a very flexible tree branch.
The sum of all fears is that the parting tool is pushed back like a spring, and when sufficient pressure has developed the tool point will be dragged into the cut, as the top slide deflects, and so you get a steady digging in effect, which double loads the tool and in the worst case the job, if it is sticking out far enough,just tries to climb up onto the tool.
The solution to your, and anyone else's problem with parting, is instantly cured if you make a solid block tool post of steel, to the height of the top slide, and having a slot in the side to mount the parting tool holder in it UPSIDE DOWN, but with the point on centre.
It just requires a sketch to get the proportions right.
This is mounted on the end of the crosslide and stays there with the parting tool permanently available.

I'll attach a photo of my capstan lathe, (they all have this arrangement) so that you can see the proportions of the tool post.
I have known some people to remove the compound slide completely, and make a solid steel spacer to mount a four way tool post on.
You lose the advantage of the compound slide for inching the tool when facing etc, but sometimes when the devil drives then needs must be.
I wouldn't recommend this method as it is only resorted to by some people when things get really bad.
Personally, I part from the front, in the normal way, but due to the flimsy design of the crosslide/compound slide set-up on my old lathe, I get traumatised occasionally and have to resort to the smelling salts and medicinal brandy to calm the nerves, and that is before parting off starts.
However all is not lost, as I am in the process of making a new longer crosslide that will have a back toolpost on it as I've described.
Ian.

"well what type of lathe was it? was it a cnc lathe? what was the material?"


I believe it was a 9 x 20 or a little bigger. I don't believe it was a cnc, but I could be wrong. The material used I think was 6 series, but I can't really tell from a picture.




handlewanker

If you're referring from the picture above, this is not my lathe (I wish it was). I was asking a question, and thought it be easy to see what I was talking about.


Wow you have definitely researched this problem. I was going to buy the QCTP and hope that this would help. I'd be really interested in seeing what you have come up with, please do post pictures or maybe even a how to?? :) :) :)

Hi twocik, been machining all my working life, started at age 14 in school metalwork room after school, about 1952, became an insatiable metal monster ever since.
It only really became a problem when I started work for real in 1958, and realised that they expected me to actually kick my habit and stop doing "foreigners" in the firms time and the rest is history, so to compensate for my curbed appetite I bought a small lathe from one of my fellow apprentices and learned rapidly what the difference was between a 20" swing DSG centre lathe in the workshop and a little 3" swing Flexispeed piece of iron mongery that went by the very dubious name of a lathe.
You just can't substitute solid mass for flimsy framework, and if you try it's a nightmare.
But that's another story.

The QCTP is a feature on a lathe that I would not under any circumstances be without.
The ability to have preset tooling that is always on centre height and orientated correctly is a feature I put at No.1 posi.
To this degree of desire I am so inured, that In 1966 I built a small centre lathe for my future model aero engine maintenence needs, realising that I wouldn't always have the firms tools to use.
Like all things mechanical you have to compromise for one reason or another, and the design was made light to allow X-ray investigation by the security force at the job I was in, which was on the diamond mines in South West Africa.
This was really necessary as I was working on the mines to save money, and when I was to leave I wanted to take the lathe I had made with me, so it had to have steel no thicker than 1/2" maximum anywhere.
A long story short, one of the features, apart from umpteen others I dreamed up, was a QCTP.
So it was design time for yours truly, and a good thing I did too, as some years later I used the model lathe to make some serious money, and the QCTP was a godsend.

Now when you're in industry for real, you have all the expertise and equipment to go wild with specifications, usually time is the hardest bit to find.
A QCTP can be made for a very modest outlay and with the very simplest of machinery, a lathe and a mill, plus a bit of heat treatment availability, nothing very exotic, but the end product is still very accurate.
I'll attach a photo of the lathe to show you what the QCTP is like, and another photo of a newer design that I am currently making, (80% finished), and this one is for my 10" X 30" Colchester Bantam lathe.
It was designed using Cadkey Light, a cad training program, that came with Cadkey in the 80's at the firm I last worked for.
I always design from the making aspect, as if it's difficult to make it won't get made.
Too many design draftsmen fail to understand this simple principle, and dream up some totally incongruous bits of illogical artwork that has to be reworked, usually on the bench, before it can be made, K.I.S.S. is never more desirable than in this scenario.

As far as parting off is concerned, most lathes except the larger models with lots of metal mass, and over sized proportions for enhanced rigidity, give trouble parting off, which as the Duchess said to the Bishop," You can be good looking, but you better be rigid".
If you take a gander at the QCTP in the photo you attached earlier, you will notice that although it is a solid block with dovetails for the tool holders, the fact that the tool holders themselves are off to the side, and not directly down on the slide top, like in a 4 way toolpost, makes them less rigid and more prone to deflect under load, which is not a problem with straight turning or boring but tantamount to a death wish when parting.
The 4 way toolpost is a tried and trusted tool set-up, much loved by the old guard and most European lathe users, but a bit of a PITA when it comes to getting more than a few tools into the firing line, but still pretty usefull.

There's a whole gaggle of options that you would want to short-list when you choose a lathe,and rarely do they all happen from the same machine tool supplier.
One of these days some lathe maker is going to do what the camera makers do and that is sell the machines to customer specifications with all the options of variety available, such as a bed with tha option of a headstock with either belt drive, gearbox or VFD motor, the list could stretch a block.

If you've got the dosh to get a QCTP, go for it, best thing since sliced bread, especially if you can get at least 8, not less, tool holders.
It won't cure your parting problems, but if you have a chuck system that is bolted on like a Camlock system and their varietys, and you have reverse capability,then you can just turn the parting tool upside down and part off with the chuck going in reverse, in the front tool post.
Quite a few lathes have screw on chucks and this prevents using reverse while cutting, otherwise you'll screw the chuck off.
Even then it's handy when you are cutting Metric threads with an Imperial leadscrew, and instead of disengaging the half nuts at the end of the thread, you just put the motor into reverse and traverse the carriage back to the beginning of the thread with the nuts still engaged.
The thread indicator doesn't work for Metric threads, or for that matter on any thread that is pitch based instead of threads per inch based.
If you don't believe me, try using the thread indicator to cut a pitch of 3/32" with a leadscrew of 8 TPI, as opposed to having something nice like a pitch of12 TPi to cut.
I might have to put the photos in the next post as the file size was saved as it came from the camera, about 2 or 3Mb.
Ian.

Here's the photos. I've even used the small QCTP on the Big lathe, photo #4, because I've got so used to using it while on the small one.
The new QCTP in photo #3 is just balanced on the top slide of the Colchester Lathe, to give an indication of how it would be when it's finished.
Photo #2 is of some of the 8 tool holders for the small QCTP.

BTW, when using a QCTP, do not move the main block around AT ALL, or you will lose the register ability of the system to keep the tools exactly on position.
This type in the photos will enable you to change tools for repetition jobs and still be dead on position to the "thou".
Ian.

Handlewanker you out done yourself, and seem to have alot of experience in this field. Have you ever thought about putting out a instructional DVD?




"It won't cure your parting problems, but if you have a chuck system that is bolted on like a Camlock system and their varietys, and you have reverse capability,then you can just turn the parting tool upside down and part off with the chuck going in reverse, in the front tool post."



So the QCTP isn't going to completely get rid of the choppy finish, but it should at least help, right?



The QCTP that LMS sells is $87.50, is this good or should I look at a different post? The reason I ask is, I see it's made of 6061 aluminum. I would think they'd use steel or something stronger (kind of like yours), but what do I know.

Or what if I made the mounting bolt lager for the tool post, you think that might make it a little more sturdy?




http://www.littlemachineshop.com/Products/Images/480/480.2461.jpg



I see in one of your photos that you're using a plate of some sort to underneath the tool. This is what I was using to heighten the 1/4 turning tools, and my current tools 5/16 tools. With any QCTP allow me to adjust the height? If so this is a no brainer(chair)


I'll try mounting the parting tool upside down and switch the motor in CCW. :)



Thank you for your help and photos. My learning curve continues....

twocik you may not want to switch your parting blade upside down as Im sure that your lathe probably has a threaded spindle nose holding the chuck on. and by cutiting in reverse you have the chance of it comming loose and hitting you in the forehead

chris

twocik you may not want to switch your parting blade upside down as Im sure that your lathe probably has a threaded spindle nose holding the chuck on. and by cutiting in reverse you have the chance of it comming loose and hitting you in the forehead

chris

Chris you may want to rethink that statement slightly. When you cut with the blank upside down you do it from the back on a seperate toolpost with the lathe in normal forward, I think you could do it reverse on the 9x20 as mine has locks also but I would not trust them.

chris

I've made a plexiglas face shield so that this doesn't happen.



Alright so let's see if I have this right. Now it's ok to mount the parting tool upside down, but at the back of the lathe (second hole)? Picture attachedPicture below



What about the QCTP, any good?

I also have found this one, but I will need to modify a few things from what it's saying. What do you guys think, is it worth it or does someone sell a QCTP ready togo?


http://www.littlemachineshop.com/products/product_view.php?ProductID=2271&category=-139540609

OR


http://www.littlemachineshop.com/products/product_view.php?ProductID=2280&category=-419988835

I'll try mounting the parting tool upside down and switch the motor in CCW.



Chris you may also want to rethink your statement... as twoick did not say anything about mounting the tool behind the work peice he said just flip it upside down and run the motor ccw. I just don't want to see anyone get hurt. Plexiglass will do little to stop a flying chuck.

chris.

twoick if your cross slide will move far enough back that you can use that second hole from behind the work than you could certainly use that one. Although I think that most people just make up a mount that will go into the t-slots on the cross slide so that they can leave it on the lathe all the time back out of the way and then just use it when they need it.

chris.

Hi Twocic, the post #42 shows the QCTP made from alluminium, this is a bad design, from two points.
#1 Alluminium is too soft for most machine applications especially a toolpost that's going to take a bit of stress, even if the manufacturers have tested it and say it will last, in my experience ally is not a material I'd use in this location, one reason being that the chips no matter how well you clean out the cavities will get pushed into the soft metal, even if this is a tough grade of alluminium.

#2 The design shows a "PISTON" type locking device whereby the plunger or piston in the centre of the locating face pushes the tool holder OUT to lock the tool holder against the dovetail end inner faces of the ally body block.
This is CRAP, when you are resisting a load you don't push it away from you but hug it to you so to say.
When the lathe is working the load on the tool is in a downward direction, trying to rotate the tool about the toolpost centre axis, and also towards the tailstock.
On clamping, the tool holder is being pushed towards the headstock by the piston in the body to lock it, and so is trying to resist the load that is coming at it from the bar of material being cut, or as the carriage is pushing the tool at the job.
For this application, it is better to have a tool holder that is being pulled to the body of the tool post, going with the load, which is why I designed the QCTP on the small lathe with this type of clamping device.
For light loads on small hobby lathes the design you have shown would PROBABLY, (dozens have been sold and are being used) be adequate, but I am of the opinion that you can't under design a requirement either for cheapness or just because it's the simplest method to produce a device that appears to do the job.
The same as you wouldn't use plain bronze bearings in the front wheels of your car when tapered roller bearings are necessary, even if you only use the car to go to church on alternate sundays, and even if both types work.

The second design you show appears to have the clamping device that pulls the toolholder to the post, can't quite see how it works, but being made all of steel, I would say this is superior, even if the price is double, quality doesn't come cheap if it's really present.

The type of QCTP that I have used for 50 years on and off, in industrial conditions, has the tool holder located to the tool post body, by 2 vertical vees and a tee type clamp in the middle, pulling the tool holder to the body.
All hardened and ground, they are excellent for total accuracy and repeatability when a few repetition jobs have to be made, even if they are pretty costly, but like all things mechanical ALL QCTP's have the one drawback that rigidity is sacrificed for convenience of tool changeability.
With heavy machining conditions it take a lot to beat the 4 way type of tool post, a condition not really encountered in hobby lathes general.

With regards to the parting tool set-up, you really want to mount the tool, upside down in a seperate block, as far as you can get it, to the back end of the crosslide as noted in post #48 by Snowy.
This will keep it always available, but back and out of the way of the chuck when you're using the front toolpost.
The lathe you showed in the earlier post, (that I admired), has two tee slots running to the end of the crosslide.
I would mount a plate on top of the crosslide and across the end, bolted to these two slots with a central block having a slot in the side to take either a ground up HSS tool bit or a parting tool holder with a parting blade in it.
Either way it would pay to make a simple drawing or sketch to scale, and project the dimensions of the crosslide height to the bed and chuck centre line so that you can position the slot to take a parting tool in whatever form you wish.
With this design make sure that you have enough room to allow for tools that are wider than normal toolbits, like a parting tool holder, or for regrinding, and just get tool height by using packing strips as normal, bearing in mind when designing it that the tool is upside down but still on centre.

Personally I would use one of the parting tools with the seperate blade, ONLY sticking out the bare minimum for rigidity, as they can be pulled out to get a deeper cut when the diameter is a bit bigger.
If you are going to use the front tool post with tool upside down and lathe running in reverse, make sure the chuck is the bolt on type NOT the screwed on, or else it will screw off under load, apart from smashing the tool and job as it move sideways.
The second design I am currently making has the dovetail at the front of the tool holder pulled into the toolpost by a piston type plunger situated at the back of the post and pulling against the back tool holder dovetail.
The synopsis is that they will all work to one degree or another but some just cost more or work better or are easier to make.
Once you have used one and come to terms with their attributes or limitations you won't want to be without one.
BTW, parting off speed is as per normal machining operations, that is 100 feet per minute for HHS, or by rule of thumb for a 1" diam job use 300 rpm, and 2" diam use 150 rpm etc. etc.
N E V E R use a slow speed if the tool chatters or kicks up a fuss, just increase the pressure on the tool slightly, and remember as you get closer to the centre the surface seed is actually slowing down and care shoud be taken to back off the feed rate.
Make sure the tool is ground correctly, SQUARE on the end, not slightly slanted like capstan lathe parting tools, otherwise you will get tool drift to the side due to the tools being flimsier than capstan lathe tools, that is unless you are a bit more experienced at turning when you can grind the end at a bit of a slant to get pipless parting off, and also have the front clearance NOT MORE THAN 2-3 deg otherwise it will self feed in, old hands use 1 deg and auto feed.
Now on a note of safety first......when using a tool in the back tool post upside down, it is a wise precaution to stick a piece of large bore plastic tubing on the end of the parting tool when it's not in use.
The reason will be obvious when you drag your hand back from retrieving a piece of material or tool from the crosslide top and contact the hooked point of the blade with the back of your hand.
Ian.

Ok so we've eliminated the aluminum QCTP. I found this Specifications chart for all LMS QCTP

It's saying wedge for the AXA Series 100, what does this mean? I not understanding how this locks into place. picture below


I have about $200.00 to spend, maybe a little more if I need to. I'd really like to find something really rigid that will withstand 3 & 4 inch 6061 aluminum material.


UPDATE

Now I just found the ajax site and they have them in Piston and Wedge, AND for almost $30.00 dollars less??? Is this to good to be true or is LMS really jacking up the prices??

http://www.ajaxjaws.com/wizzc/wizzp.html






Harbor freight sells a QCTP, but I'm not sure what it's made of.


here

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42806

Twocik,

I bought an AXA-100 Wedge type QCTP from SHARS (DISCOUNT TOOL) on ebay. I paid $119.50 plus shipping for it. I use it on my Grizzly G4000 9x19 lathe. I use a BXA size on my 12x36 lathe.

I bought a HF piston type qctp (39083?? -- AXA size) that fit my 9x19 but the quality was nowhere near as good. It wouldn't lock the tool holder in position on one of the slides. (Now I have two sets of tool holders.)

Alan

Alan,
Did that QCTP for the 9x20 work well or did you have to screw around with the mounting stud? also is there a make or is that a generic?

chris

I'm in need of a QCTP badly, can someone confirm a good tool post to buy?? I'd like to order one tomorrow, along with new turning tools & heavy duty boring bars. Please anyone... :)



I also just read that the ajax wedge tool post is the one togo with, not the piston post. The review was saying something about it being more sturdy and precise. Can anyone confirm?

i have the a2z cnc qctp, a piston type, and it is kinda flimsy, when i get some money i plan on buying a wedge type.

Hi all, just looking at the Harbour Freight model, the 42806, it would seem from the design that it will locate and hold the tool holder firmly by nature of the split in the body being squeezed closed and gripping the tool holder.
Provided the QCTP body is made of steel, I would think that this is an ideal design for the money, but not having used one I can only go by what I would look for as regards to rigidity when clamped and most important repeatably locating when the tool holder is removed and replaced.
The locking method is by a nut on the side of the block that squeezes the split in the block to grip the toolholder, and this is a slow way of unlocking the toolholder, but very adequate for the job, PROVIDED that a ring spanner or socket is used to unlock it as an adjustable spanner will rapidly damage the nut after a few tighten and untighten cycles.
For the money, $99.00 if I remember rightly, this is very affordable.
While the wedge type and the piston type give quicker action, they by nature of the design are weaker in their holding power.
The type that I designed and made myself has been used on steel bar 6" diam taking cuts about 1/8" deep, which as the tool was designed to be used with a smaller lathe is pushing it to the outer limits, but it still does the job.
One of the main reasons I use it is because it will repeat the holding position accuracy when removed and replaced.
Ian.

Alan,
Did that QCTP for the 9x20 work well or did you have to screw around with the mounting stud? also is there a make or is that a generic?

chris

Chris,

I originally made an adapter to screw on to the top of the existing stud. It was never quite satisfactory. When I got the new qctp, I drove out the original stud and drilled and tapped the hole for the 14mm metric stud that came with it. It works like a dream. The one from Shars (Discount Tool) is a generic AXA wedge type. It is not quite as nicely done as a PhaseII or an Aloris but works quite well.

Alan

I have been bouncing around about making my own, a friend did for his altas-clausing, but then again he said that had he know you could get one cheap he would have bought it. Now as of today I own another 9" so I might invest in a set of good tool posts, depending upon what I find is wrong with this new logan then tooling is that much easier.


My wife asked me why do you need to two lathes and drill presses(we were on a cast iron crawl as I say)? I quickly corrected her, honey I have 4 lathes, 3 drill presses, and for the moment 1 shaper and 1 mill.

chris

Yep, can't have too much machinery, I guess the ladies don't understand the power you have when at your command you can dim the lights and make the TV's for miles around flicker.
When I run up my capstan lathe with the 3 HP single phase 2800 rpm motor it creates a bit of a stir.
I almost joined you with that buy all habit when I got another lathe going cheap on Ebay last week, but a mate of mine wanted one bad, so I let him have it.
It's a Hafco AL 150, or as sold in UK an Emco 8.
A very basic lathe, missing the fixed and traveling steadies and some of the screwcutting gear train, so he'll be busy for a while tooling and refurbishing.
Ian.

Hi twocic, re post #11 where you show the end of your lathe with the belts and gears.
I don't think this is a "clutch" in the truest meaning of the word.
If you have the belt on the largest pulley it will slip off if you move the lever back while it's running.
Unless the book says otherwise, it's a "belt tensioning lever", and sholld only be moved when the lathe is stopped to shift belts from one pulley to the next.
The reason I think this is because I just got a lathe on Ebay, a Hafco AL 150, and the belt set-up is exactly the same.
There is no way that the belt will stay on if the lever is moved while it's running.
The other thing is, on the lathe I've just got, the final drive belt is a piddly narrow vee type belt, about 3mm, (1/8") wide, and is starting to shred up, so a new belt is wanted.
I am going to have a look at replacing the belt with a 1/2" wide Poly Vee belt and either add some material to the rim of the pulleys or just make a new set wider from steel or ally.
Ian.

HA, you can never have to many tools.


For anyone that has been following the thread, I went with the AXA 100 Piston. WHICH I GOT ON SALE at ENCO for only $90.00 (free shipping), WOO HOO The post is made of steel, not sure of the grade, but it's at least steel.



http://www.use-enco.com/CGI/INSRIT?PMAKA=505-2253&PMPXNO=953080&PARTPG=INLMK32



I'll let you guys know how it turns out.

Hi, happy is the man who knows what he wants and gets it. (he's also one of the seven dwarves).
You should be able to copy the toolholders and save a bundle.
I reckon to have 8 tool holders, with 7 permanently loaded, is the bare minimum for tools you use all the time, with one empty for the odd occasion when a special tool is required.
I don't have a drill chuck holder for the QCTP, as it puts a lot of strain on the carriage and tends to want to twist the toolpost out of allignment.
Instead, because you usually need a variety of drilling operations just to drill a single hole, I use a tailstock turret attachment, that fits in the tailstock spindle morse taper, and gives me 6 tools without having to constantly open and close the drill chuck.
Ian.

Ian it seems as though you've got quite the little production lathe there. sounds good!
chris.

Twocik,

I posted this originally on your DIY Coolant system thread, but it probably should have gone here instead.

Alan

Originally Posted by twocik View Post
Ok the AXA 100 QCTP came in and now I need to figure out what mods I need to make to the post. I was told to drill and tap the post hole and that's it, but well see.

twocik,

I took off the top of my compound and just tapped on the top of the original tool post bolt and it came right out.

My new mounting bolt was a 14mm x 1.5mm pitch. My drill chart calls for a 12.5mm drill bit (0.4921") for that size tap. The next smaller Imperial size is 31/64" (0.4844") and the next larger is 1/2" (0.500"). Since the compound is cast iron, drilling it to 31/64ths should work, because cast taps easily.

Alan
__________________
http://www.alansmachineworks.com

Hi snowshovel, the production components I mentioned were originally set up for a specific job I was doing, and I don't normally use the tailstock turret attachment for ordinary use.
The QCTP is so much used that the original one I made for a small 4" swing lathe was pressed into service and remained in service for 10 years until I decided to design a new one to fit the bigger 10" swing lathe, now almost finished.
One other modification I would like to make is to bore out the spindle nose to accept ER 40 collets, but this is such a radical change to a lathe that most people would shy away at even contemplating it.
The spindle nose is most often equiped with a Morse taper, for between centre work, but as I ALWAYS machine a soft centre on a piece of mild steel held in the 3 jaw, and just true it up with a small recut, I am in the position to think about the modification.
One of the main reasons is the ability to hold work from 1/8" diam up to 1" diam dead true, and as the ER collet system in the Metric sizes allows for a 1mm squeeze down, you are able to get a stepless holding range from 2mm right up to 25mm.
There are a number of factors influencing the move, #1 being that my chuck screws on, and the ER system requires a specific nut to close the collets, so the spindle chuck thread will have to go in favour of the Camlock type of fitting or the other type whereby the chuck has studs and nuts on the back and attaches to the spindle via a fixed backplate with holes and a rotating collar, simple to make and very accurate locating, just requires designing and making.
Ian.

Ian that would be a pretty radical design change to the mill. why not just buy a screw on er collet chuck?

Hi snowshovel, yes you're right it would be like brain surgery, only contemplated as a way out option.
A screw on ER chuck body if available is not an option as it introduces another interface and some overhang, while having the collets directly in the spindle end ensures true running and rigidity, nice to think about when all the other mods are finished, probably in the end a new spindle would have to be made, so the old one can remain stored in "pristine" 1920/30 condition.
The most desired item is the QCTP I've got on the go, which is almost finished, so then I'll be able to join the ranks of the priviliged few, after which I want to think about a QCSCGB and then a QCSC and then............
Ian.

Hello guys,
I've bought my QCTP and tried to drill and tap the 9/16 bolt that came with it into my original compound slide. Well it didn't work, so I'm now waiting on another from China. In the mean time I need something to get me by or a method to replace it. I've seen a few others using different methods, and wanted to know which is the best way of mounting my AXA 100 QCTP.


SJH if you're still with us, how did this compound mount hold up? I've bought a 2" thick 4 x 3 1/2 piece of steel, and almost have it squared and ready for machining. Man it's a pain to cut thick steel, especially with a miter saw.


http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/gearedcrossslide017.jpg

http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/gearedcrossslide016.jpg

Hi twocic, can you be more specific, what happened?
Did you try to put a thread in the compound slide top and couldn't?
The photo of the lathe is not quite clear as to what is happening.
Looks like a humungeous chunk of metal on the crosslide, is this the mounting block for the QCTP?
Ian.

Ian I don't think that is twocik's lathe in the photos I beive it is S J H's correct me if I am wrong. but yes twocik what exactly went wrong when you tapped the compound? if you just simply stripped the threads or messed them up there are many ways to get around this, if the tap broke that is a little bit harder but still not imposible but, more information is needed.

you cut a 2 x 4 hunk of steel with a miter saw? wow hope you were wearing safty glasses or maybe even a full face sheild haha.

chris.

Hi twocic, can you be more specific, what happened?
Did you try to put a thread in the compound slide top and couldn't?
The photo of the lathe is not quite clear as to what is happening.
Looks like a humungeous chunk of metal on the crosslide, is this the mounting block for the QCTP?
Ian.

Ian,
Unlike every other lathe in the world the grizzly has a stud which sticks up, you have the option of trying to replace it with something of more robust construction for the tool post or make the hole in the tool holder smaller. I am not a fan of either, I am thinking that he tried the first option and found out that the metal is fairly hard.

chris

Did anyone notice something missing in SJH's picutres?

I wonder if that is a precursor to a cnc.

chris

Sorry gentlemen, I was using SJK pics as an example of what I'm wanting to make (compound mount). I'm was wondering if it's a better solutions than using the top slide.


Now what I did wrong with the mounting of my new QCTP was,

I tried to drill and tap my top slide to accept the new QCTP bolt 9/16 (LMS recommends this). I drilled the hole and taped it, but when I tried to tighten everything down using a wrench, it would move with just a little bit of force applied to it. After everything was as tight as I could get it, it still wasn't good enough. What happened was, the 9/16 bolt didn't have any sort of shoulder/stop, so it ended up going right thru the hole I just taped. I don't know if it's just me, but the cast iron ( I believe) that the lathe is made with is very soft and almost chips away...



"you cut a 2 x 4 hunk of steel with a miter saw? wow hope you were wearing safety glasses or maybe even a full face shield haha."

Oh yes I sure did, safety glasses is a must in my little shop!! I've been using my saw for just about everything, and yes I've used it to cut steel (no problem). Now it being so thick makes its a little harder to cut, but I've had no problems with it. :)

Hi Twocik, as usual I got the wrong view of the situation, but anyway as the top slide is a bit wonky now you can still recover it and make it stronger by the method that my old Colchester Bantam has.
Instead of a tapped hole in the top slide for the holding bolt I've got a bolt with a ROUND head that is inserted in a counterbore from underneath the topslide, and has a small peg to stop it turning when tightening down.

This is much stronger and doesn't rely on the threads in the metal to hold the bolt in.
To do this on the lathe intended you would have to first mark out the centre of the bolt hole on the back opf the topslide, usually the mid point side to side and half that distance from the end to the bolt centreline, then set up the topslide in the four jaw chuck and bore the hole and counterbore from the backside.
How can you do this when you need the topslide and tool post to mount the tools in?
Well sometimes you have to bend over backwards to achieve the perfection required.

You will have to make a temporary toolpost
If you have a slotted crosslide like in the photo, then just get a piece of 1/4" steel plate and drill 4 holes in the corners to fit the crosslide top.
Then get a piece of 4" square tubing, thick walled, and weld it to the plate.
Next get a piece of 3/8" steel plate about 4" square and weld it to the top of the square tube.
Make sure the bottom face is flat by whatever means available, grinding,filing or turning, whatever.
Drill and tap 1/2" or 5/8" in the middle of the top plate and make a plate clamp to hold the tools down.

The tubing should be long enough so that when the tube and welded plates are stood on the crosslide the top will allow a 1/2" tool bit or boring bar to come to centre height, allow for a few packers.
Once you have this item you can bore a neat hole and counterbore for the new bolt design.
The bolt will want a head at least 1/4" thick and about 1" diam, this will also depend on the THICKNESS ( very important) of the topslide around the old tapped hole, at least 1/4" to 3/8" thick for strength left after counterboring.

The thread on the other end to take the handle or holding down nut on top.
Using this method will allow you to really tighten the toolpost down without it pulling out of the topslide.
You could also turn up a 1/4" thick washer and weld this to the end of the existing bolt and then turn it true in the lathe with the set-up mentioned, making sure that the corner in the top slide is sharp and the bolt head slightly chamfered, about .010".

When you've finished with the makeshift toolpost you can bolt it on the rear end of the topslide and use it as a back toolpost for a parting tool, so it pays to design to the requirements and make a neat job.
Ian.

Hi Ian,
Do you have any pictures of what you're talking about? I kind of follow, but would like to see what you're talking about. I don't own or know how to weld TIG/MIG. Would love to learn, but at this point my money is kind of tide up.


What I was going to do is mill a surface that looks like this out of the steel block I have below.

I'm late to the party on this thread, to your very first question, knowing what cutting tool to use becomes infinitely easier when you understand the basic cutting tool geometry, rake and clearance angles. you'll be amazed at how simple this is....pick up some texts and/or google the US army machining lathe book (its free & online) - it will cover the basics. The two tools I use the most are not in those pics, a left hand knife tool with chip breaker and facing tool with a chip breaker. imo you should do is buy a dozen hss blanks just little square lengths of hss. Then you will be much more willing to make mistakes, grind away and learn what works and what doesn't. after awile you will have dozens

also, Harold at the Chaski home shop forum has put a lot of work into an excellent write up with pics on how to grind tool bits. worth checking out, think its in the general machining section.

Its good to see you making the effort on this. I think a lot of newbies erroneously assume because carbide is more expensive in the tool catalogs it must be better. well it is, if you've a large industrial lathe and are focused on removal rates. For the small lathes, better workmanship will follow learning how to use hss. Two reasons, because a more acute angle is used the cutting force is much lower (which these light machines like) and second you'll learn to sharpen, change angles and grind special shapes to suit materials and jobs, not easily done with carbide

and its cheaper.

and listen to what Ian says :D

SJH if you're still with us, how did this compound mount hold up?It works very good.
That is a solid tool riser to replace the compound. The 9x compound slide and clamp as you probably know is quite poorly made. The solid riser block allows much heavier cuts from this lathe at the expense of not being able to turn tapers etc. But if you rarely find the need to use the compound slide then this will be the most rigid setup to use.

Many guys will make a new clamping setup for the 9x compund and that is a major help. But the 9x compund is still fairly weak even when rigidly clamped.

I ended up doing a 7x compound conversion which is nearly as rigid as the solid riser block from cut comparisons. This is my current setup on this lathe- http://i109.photobucket.com/albums/n48/S_J_H/9x20%20mods/7xcompoundconversion023.jpg
The 7x slide is much nicer IMO than the 9x. But the conversion did involve a good deal of work.
I have a lot of pics comparing 7x to 9x compounds side by side here- http://s109.photobucket.com/albums/n48/S_J_H/9x20%20mods/?start=all
Did anyone notice something missing in SJH's picutres?

I wonder if that is a precursor to a cnc.
Nope no cnc for my 9x20. I'm in the middle of building a cnc bench lathe from scratch.:D

Steve

"I'm late to the party on this thread, to your very first question, knowing what cutting tool to use becomes infinitely easier when you understand the basic cutting tool geometry, rake and clearance angles. you'll be amazed at how simple this is....pick up some texts and/or google the US army machining lathe book (its free & online) - it will cover the basics. The two tools I use the most are not in those pics, a left hand knife tool with chip breaker and facing tool with a chip breaker. imo you should do is buy a dozen hss blanks just little square lengths of hss. Then you will be much more willing to make mistakes, grind away and learn what works and what doesn't. after awile you will have dozens "




Yes I've found a few sites that really helped, and I know what you mean by it gets easier after you see which tool is used for each job. Took a little while to understand how to get a nice surface finish, but I got the hang of it. I've tried to make a few tools, but didn't come out to well. It's definitely something that needs practice, but that's after I finish my invention. :) It's an art making tools, something you have to take in with nothing else on your mind.




SJH thank you for the response. You have made a ton of very nice things, and the block is a definite one I really like. Now I see what you mean about the angling, but can't you loosen the QCTP nut and position that for the angle needed, then retighten nut?

How tall is your steel block that the QCTP sits on? I see that you used the little steel black threaded plate that comes with the QCTP. :)

Hi all, one of the golden rules with machining, and that is RIGIDITY.
Whatever the method you use to remove metal, make sure that the tool is well supported, and that goes for the machine right down to the floor.

I once worked on an an old belt driven lathe that used to do the fandango every time the top pulley was used.
I got over this by dragging the lathe closer to the office wall and wedging it against the doorpost.
Next morning it had moved a foot away.

This happened every day for a week, and on the Friday I was doing a bit of top pulley work, when the boss came out of the office and without a word switched the lathe off at the wall, grabbed the end of the lathe and bodily pulled it away from the wall.
Apparently it was causing a vibration that went through the wall and rattled the window frames.

I've been looking at the photos by SJH on the 9X20 mods, man that fellow has patience.
I thought I was a bit of a wangler, wanting to change things the makers had dreamed up, but then I saw the crosslide mods using a stock material, (allthread?) instead of a left hand thread made for the job.
So that was what the geared mechanism was for at the crosslide front, a reverse gear.

I won't mince words, but IMO it is a heap of crap.
I've modified machinery for one reason or another, but I've always kept the design as pure as possible, that is by not making some outlandish feature to cater for an inadequacy in the modification.

Why didn't SJH just turn up a new spindle and screw cut it left hand as was the original spindle?
CAN'T SCREWCUT?????? I don't believe it. I'll take a few more pills and calm down a bit.

While I like the Chinese lathes, (I think it was the pea green colour and the neat lines), except for the the fact that they have forgotten the very basics of lathe design, and push these horrors on the market, marked down to guarantee that the local lathe makers to be would not/ could not compete, and making a lot of Newbies suffer for inadequacies that more experianced persons just accept and go on and modify the living sh##ts out of them to make them perform.

Some 20 years ago a range of Taiwanese lathes, in the lower price range, came on the market, also very cost effective, and I might add very well designed, robust very functional and fully equipt.
Perhaps it was the workshop standard machinery grey colour that made me tune to the fact that although the design was just a bit more than 1920 lathe design, the lines and proportions were so well balanced and they didn't have SCREWED ON CHUCKS!, no sir, they sported Camlock.

Basically the layout was with a three speed Vee pully headstock, with the pulleys between the head bearings, (ball races not bronze), and a set of back gears for low down torque, and a high and low pulley reduction on the motor, giving 12 speeds alltogether.
The first thing to do was to cut the vee belt off of the head pulley and fit one of the segmented belts, otherwise you have to strip the main spindle out to replace the belt.
I worked on one of these machines at a friends place when I was rebuilding my lathe and coming from an industrial environment felt quite happy with it's performance.
It grates me to see a machine that is adequately made and equipped, but with glaring design faults, faults that make me wonder where these people learned machine layout.
A typical example is the Grizzly 9X20 belt arrangement.

twocic, I'd get a simple cheap arc welder, 120 amp model,basic tool kit, and learn how to use it, opens up a whole list of options.
I'll see if I can post a photo of the toolpost bolt arrangement I mentioned.
Ian.

've been looking at the photos by SJH on the 9X20 mods, man that fellow has patience.
I thought I was a bit of a wangler, wanting to change things the makers had dreamed up, but then I saw the crosslide mods using a stock material, (allthread?) instead of a left hand thread made for the job.
So that was what the geared mechanism was for at the crosslide front, a reverse gear.

I won't mince words, but IMO it is a heap of crap.
I've modified machinery for one reason or another, but I've always kept the design as pure as possible, that is by not making some outlandish feature to cater for an inadequacy in the modification.

Why didn't SJH just turn up a new spindle and screw cut it left hand as was the original spindle?
CAN'T SCREWCUT?????? I don't believe it. I'll take a few more pills and calm down a bit.

Thanks for your input and yes I can cut very nice threads on a lathe,lol

The purpose of the 2:1 gear REDUCTION driven cross slide was for a few reasons- #1,to allow the cross feed handle to always clear the compound no matter what angle or area it is set at, #2 , a 40 pitch feed without fragile threads, #3, I get direct diameter reduction reading on the .050" dial and #4, IT WAS A FUN LITTLE PROJECT!
It face cuts and parts very nice with the 40 pitch feed.

Try and remember many of us enjoy modifying and even building machines as a HOBBY. It's what I do for my hobby as well as making very functional parts for my race car, to building model engines that just sit on display.

Right now I'm building a cnc small bench lathe from scratch..... for fun! Do I really need it? no but it's a nice challenging project for me.
Hiwin linear rails, dual preloaded ballnuts, pneumatic turret tool changer etc. Yeah fun stuff for this guy!
http://i109.photobucket.com/albums/n48/S_J_H/cnc%20bench%20lathe/cnclathe.jpg

Steve

Thanks Ian!! What was the name of the company/lathe? Sounds very promising, I'd like to see the difference.



Yes I do need to learn, but I'll have to save up for this one. I would like to learn how to MIG and TIG. Maybe a machine that can do both. :)





SJH How high was your steel block? I'm going to cut it tomorrow with my mill, that way it's all one piece. What I'm getting from my measurements is 1.2" - 1.5" range. I'm worried about the steel platform being at the right level for the proper QCTP adjustment.

PS: Your lathe is looking GOOD!!!!!!! :O

Thanks twocik.

The total height is around 1.25".

That base was made from an old cast iron press plate I had lying around. It was not quite tall enough so I also used the plate that came with the tool post.


Steve

Hi Steve, I'll still pick holes in things that offend me, machinery wise that is.
I take your point, it's great fun and a way to relax when you've got a designing side to your nature, and if you can improve where others put up with innefficiency, then it's to the better.

As you have said that the crossfeed screw is a stock item, what was your source of supply, and what kind of tolerence does the pitch have?

I blanche to think that it was "allthread", but on consideration of the requirements of a centre lathe crossfeed screw, the only accuracy is ever on the last cut, when a few thou is dialed in, and so it wouldn't matter if the pitch varied by any amount, unlike a mill X axis screw that has to cater for co-ordinate positioning etc.
On the other hand I think you said that you were using a DRO for positioning, in which case it wouldn't matter if the crosslide was dragged across by a bit of banjo cord wrapped round a stick.

I wouldn't dream of criticising your project, too damm nice looking to even fault it.
Just one thing I'd like to know,and this applies to Chinese machines as well, in the photo you have a massive drive belt from the motor to the first pulley, (gearbox?) but to the headstock drive you have two skinney belts, what is the reason behind this?

I always assumed that there is less torque to cater for in the primary drive input than the final drive output where there is usually a low speed hi torque factor present.
I'm not a great fan of rear end drive as opposed to middle drive input, just my preference.

If you haven't already discussed it before, what's inside the headstock, that is, the bearing arrangement, taper roller, angular contact, not bronze I hope, although they tell me some of the best toolroom lathes had bronze bearings, just can't hack them myself.
By the look of the layout you are using a VFD, is that 3 PH or 240V DC?
I look forward to seeing the progress.

By the way, 3 jaw chuck on CNC? I'd have gone for a collet setup.
What's your design criteria for the lathe to handle, not bar work for sure, short bars maybe or billets, just curious.
Ian.

Hi twocic, that lathe was a common or garden Taiwanese lathe, supplied by Herles, now Hare & Forbes, in 1980 in OZ.
About 6" (12" swing) centre height and with a long bed version of about 4 ft between centres.

In your neck of the woods the name would be different, but it would have been around the early 80's.
I'm adding a photo or two of the counterbored compound slide set-up I mentioned, with the screw to show what it does.
Your set-up might be different to mine, but if you can recover the previous compound slide you might be able to rework it to suit.

There's a photo of my existing QCTP, a small one, and one I'm presently building for my bigger lathe, both have 8 tool holders so most cutting variables will be met.
What milling machine are you using to mill that block of steel? Gotta be sturdy.
Ian.

Hi, here's the photos.
#1 is the bottom of the compound slide with a threaded bush inserted to take a smaller screw size.
#2 is the small QCTP that I'm presently using.
#3 shows the QCTP stripped down.
#4 the 8 tool holders.
#5 the bolt that was previously in the compound slide showing the head.
#6 the new QCTP in a half finished state.
#7 an indicator gauge for setting tool height on centre.
Ian.

I have one of the lathes you may be talking about it was made in 1978 and is a takang 101 bench lathe made in tawain it has the belt drive headstock with a back gear. very nice little lathe heres a picture of it. Kind of messy but this is a picture of it before I got it.

http://i194.photobucket.com/albums/z150/snowshovelbmx/lathe2.jpg

chris.

Looks very nice Ian and thank you for the pictures!

Are these all made from steel or are they from a cast?

What's the angle gauge used for in the last picture?


Wow that lathe is older than me. Now that I think about it, my uncle had a lathe that looked like that when I was a kid. I remember the two gear levers at the bottom. It's like mine, but I only have one. I guess over the years they found cheaper ways to make them, and now guys like me suffer having to upgrade them to fit standard needs. In a way it's a I guess it's a good thing, teaching you the machine and how to use it properly. There's alot of time and money that needs to be invested, but you save money in the long run.

Ian,
I'll try and answer some of your questions.
Sit down and take a deep breath...Yes you have a keen eye, the cross slide screw is 7/16"-20 allthread on my 9x20. :rainfro: I used it to save time with that project but it is pretty accurate. At least in the only 4+" of travel I have on the cross slide. I can not even measure an error in 1" of travel with a conventional dial indicator. Good enough for me and no reason to make a new one from scratch.

The reasoning for the belting combo on my cnc lathe project is fairly simple. I use a toothed belt from the motor to the jackshaft. Reasons- You do not need heavy belt tension to avoid slippage and it places a lot less load on the little DC motor, but the timing belt "cogs" and to try and isolate that effect from the spindle I am using dual polyflex 3mm belts from the jackshaft to the spindle. These belts are the smoothest running belts you can get IMO. They have a 60' wedge and can transmit a lot of power in a small sized sheave.
If you look at my 9x20 pics you'll see I made a second low range pulley to be able to use dual 5mm belts. The 9x20 lathe suffers from belt slippage at low speeds and heavy cuts( I won't even touch the horrid clutch issue as mine is long since removed).
Anyhow, In my testing of how much additional power I could transfer with the extra 5mm belt I rigged a torque wrench and chucked up a grade 5 3/8" bolt and spun the spindle at around only 25rpm. Well normally I could stall the spindle and slip the single belt at such low speeds. Now it will twist the bolt in half!
So I used 3mm belts instead of 5mm for this smaller cnc lathe as I am only using a 1/2hp motor vs 1hp on my 9x20.

That 3 jaw chuck is sitting on my cnc project lathe only for setup/build purposes. My very first project will be to make a ER32 chuck for it. I made one for my 9x20 already and it's in those pics. Notice the nice threads I cut on the er 32 chuck if you think I used all-thread for the cross slide because I can't thread on a lathe :D

I'll be running a Minarik DC drive on the little cnc lathe. I run a 3ph VFD on the 9x20.
The little cnc lathe has a center distance of 12". It's for short smallish parts. One off hobby stuff.

The headstock is adapted from a 7x Chinese mini lathe. I used it because the housing is cast iron and having owned one of those lathes I knew it was not to bad. The bearings are deep grooves. I plan on upgrading them to tapered rollers though.
Don't rush to judgment to quick by looking at my cnc lathe pics. I only began this project about 2 months ago and there is a lot of work left and I am sure I will make many changes along the way.I am sure once it is operational I'll find many things I need or want to change. I could wait until it was all finished to post pics and talk about it but a lot of guys like to see works in progress.

Steve

Hi all, the QCTP and holders are all made from nickel chrome steel, left in the natural state and oil blacked, as hard as....but I had the material available and they won't fall apart in a hurry.

The gauge in the last photo, if anyone's interested in making one, is a tool height indicator.
I made it from 316 stainless so that it would always be shiny.
What it does is to measures the height of the tool relative to the centre, beats holding a ruler up to the tool edge and bending down to squint at small graduations.
It's graduated in 1/4mm increments, and covers 2mm above and below centre, with a 10:1 magnification ratio.
When you have a QCTP it's a breeze to just loosen off the height setting screw and set the height of the tool, used for initial setting of a tool to centre height.

Having used a piece of steel plate with a line scratched on it for years, I decided to make an indicator to MEASURE as opposed to indicating the tool height, so that you know to within 1/4mm or .010" the tool height at a glance.
I like to have my tools at centre height with boring bars set a bit above centre.

Now here's a thing for you, the photo of the lathe in post #85 shows the compound slide with a very sturdy base mounting, the type that has two "ears" coming out from the sides for the holding down bolts.
The whole compound slide base is spigotted into the crosslide top face and usually has two tee nuts running in a slot beneath it, very strong and typical of the needs for rigidity.

That lathe in the early 80's in OZ, sold for about A$1500 when wages for skilled workers were around A$400 a week.
As basic and without frills as they were made, the addition of the QC screw cutting gearbox puts them into a special bracket today, when trying to bid for one on Ebay, still going for around A$1500 to A$2000, if you can find one.

I find that the prices have not changed much over the years, which is counter productive to value, as to cater for the demand and keep the price down, the quality suffers, something has to give.

I recently bought on Ebay (where else?) a Hafco AL150, or as it was also known an EMCO 8, about 9X20, for A$400, quite a bargain, but the box only had so much for the money, a 3 jaw and 4 jaw chuck, a drill chuck and that was it, no steadies or face plate or gears for screw cutting, not even a four way toolpost, just one of those plate clamps that held a tool onto the compound slide top, and also missing a bit of the screw cutting gear set mounting.
At least it was in good condition, and was a good starting point to adding on the frills.

I bought it in a moment of bargain finding euphoria, but it was for a mate, so he got it, even though it cost A$140 to have it courier'd from 900KM away to his place.
Here at the pickle works life goes on, and with a collection of old iron it's sure to be a busy future, tweaking and refurbishing.

I just had a look at my own lathe's compound set-up and noticed that there is just one screw to the side of the centre mounting spigot that clamps it.
That's porobably one of the reasons I have parting off complications.
That will have to be amended, as well as the list of other inadequacies that have reared their ugly heads.
No rest for the wicked.
Ian.

The gauge in the last photo, if anyone's interested in making one, is a tool height indicator.

I skipped over that one at first.
Very neat little tool Ian.
I'll have to make myself one!

Steve

Hi Twocic, don't be put off by a lathe that lacks a bit of necessary features.
With a bit of ingenuity, you can make music that would charm the bells off a Franciscan monk.
I find it's good for a learning curve or just the satisfaction of making a bit of useless iron into a usefull tool, and in addition you learn to appreciate the limitations of metal working procedures.

In the meantime you gain the vital bit called experience, which only comes when you've opened the can of worms and pushed the envelope of modern technology to suit your requirements.
I'm sure if you have a problem you'll find a hundred solutions on the forum.

I know it's a daunting task to attempt to hack into pristine metal when you've just bought a new machine, much easier on old iron, but somewhere along the line, if you use your loaf, you can only improve the shortcomings to suit your needs.
Ian.

Hi Steve, I can honestly say that over a period of time a lot of gadgets get made, and most of them end up in the bottom drawer, as being impractical or just too time consuming to use, but this little gadget is used constantly, especially when you get tired of peering at itsy bitsy rule markings for centre height determination.

I made it from stainless so that it wouldn't rust, but the principle is simple.
As long as you get a 10:1 ratio or therabouts, you'll find it very usefull, especially if you like a bit of perfection with tool height needs.
Now I've got a mate who wants one too, so he'll have a bit of spare time to burn up.
Ian.

SJH

One more quick question about the QCTP block.

1. If you had to redesign the QCTP block would you have made it a circle for the QCTP to sit on instead of a square? Making it easier to angle the QCTP for different angle cuts, more stable not hanging off the side of the square or do you think this I'm looking to deep into this?


Thanks for the help guys, really appreciate it!!! :) After I finish this for my lathe, I'm left with is making a coolant enclosure for my mill.

Hi Steve, I would have gone for the Polyvee belt type, don't know if your'e familiar with these.
The belt is pretty thin, and has about 5 or 6 mini vee's on the inside, ideal for getting high torque drive without slippage when you want to run small pulley diameters with big pulley diams for speed reduction etc, and still have the flexibility to get round the small diameters without breaking the back of the belt as would happen if a normal A section vee belt was used.

The belt is as smooth as a flat belt drive, without clips, and doesn't have the problem of throwing off when the drive is slower and heavy, ideal for grinder heads.
The pulleys are easy to make from alluminium, as they start out as a flat pulley, no coning or side flanging required, and just get shallow Vee grooves inserted in the surface, and as long as the pitch of the vees and depth is accurate, no problem.
A belt tensioner is usually applied on the back side near the drive pulley to tension and increase the surface contact area wrap around.

I agree with your preference for tapered rollers for the headstock, but only for a heavy cutting force requirement.
For higher speed requirements I would use angular contacts, two together in back to back configuration, at the chuck end of the headstock, and two radial ball races end floating at the drive end lightly spring loaded endwise to take belt pull.

I've come across the same "clutch" problem you had with the lathe I've just bought, and have come to the conclusion that it isn't a clutch at all, not even in the wildest imaginings of a Chinese lathe designer on happy pipe time, but a belt tensioner to allow slacking of the belts for speed changing.

Some years ago I fitted an electric clutch from a cars airconditioner, to my capstan lathe and also my centre lathe.
If it is suitable for running an airconditioner from an engine doing 4000 rpm it certainly suits my lathes at 1500 rpm.

I see you've got an ER32 planned for the head, how about an ER40, which will go from 3mm to 26mm, (1/8" to 1"+), in a stepless progression of 23 collets.
I had a catalogue price from USShoptools.com a month ago, for ER 32 and 40collets at US$15.00 each
I would definately, (not even debatable), mount these directly in the spindle end for ultimate accuracy and rigidity, especially where high speed is involved, but this is only my preference and might be a bit of overkill.

I highly approve of the 3PH VFD drive for the 9X20, just bought a VFD 3PH converter 1 HP capacity, 240 volt single phase in 240 volt 3 phase out, with ramp up and down, dynamic braking and speed range from 15% of motor to 200%, which I will use for to my centre lathe and other drive requirements.

I'm currently changing all my electric motors to 3 PH as they're so cheap to buy, and now I'll have a complete speed control on all of my machines.
I'll be watching your progress with the CNC set-up with interest.
Looks pretty cool at present.
Ian.

Ian the lathe in post 85 was had for 800 US dollars on ebay. and it was only an hour away so I drove to pick it up myself! needless to say I was a very happy camper.

chris.

twocik, Round is probably a better choice. Remember without a compound slide the only angles or tapers you can cut will be limited to small tool bit chamfers unless you offset the tail stock, and threading will have to be done with straight infeed.

Ian, I had thought about a poly V setup and I am very familiar with them. Yes that type of belt is a very good choice. I have made several 8 ribbed pulleys for automotive use. But I'll wait and see how the machine runs with the current setup.

I was not talking about the belt tensioner on the 9x20. Yeah you can sorta use it as a soft start engagement clutch by slipping the belt, but it's really just a belt tensioner release lever for changing belt location.

There is a ratcheting ball bearing slipper clutch in the jackshaft drive pulley on these lathes. It is supposed to be some sort of over load device. It only functions ( is a major nuisance and limit to spindle power) with the belt drive in the lowest rpm.
The clutch has spring loaded balls that lock into detents. When to much load is placed on the belt the balls will overide the detents and then the pulley slips and stops power to the spindle. In theory or maybe on the much better made Emco compact 8 it works. On the import 9x20 it is so crudely made it's a joke and slips way to easy.

I'm going to make a er32 chuck as I already have a full set of ETM er32 collets and the spindle bore on the little cnc lathe is only a tad larger than .75" anyhow. er32 intergral to the spindle is a good idea. I have not really thought about that. I'll have to take a look at the spindle to see if it is possible.

Steve

Hi Steve, so the clutch is just a safety device in case you get wound up in the swarf, or as someone recently up our way "went through the wringer" when some emery tape he was using wrapped round the shaft and also his arm, nasty, felt sorry for his widow.
I'll check the lathe I just got for my mate in case he gets an attack of the dreaded stop in the middle of a cut syndrome.

I'm wrestling with the idea of one day doing the spindle mod for ER40, but that will also mean changing the chuck screw on thread to the thread of the ER40 nut, which as I want to have a camlock type of chuck retainer anyway makes a design a bit difficult.
I've got a basic set of ER32 collets and chuck also, but fancied going to 40 for the larger diam, quite a big outlay.
I suppose I could always let the thread just intrude into the chuck body but not do anything, early days yet, it'll mean a new spindle probably.

Chris, that was some bargain, even if it wanted work or chucks replacing.
Ian.