Hiya guys, following on from this thread (http://www.cnczone.com/forums/showthread.php?t=10247), I am going to attempt to make the auto lathe turret as found over here (http://www.issintl-inc.com/latheturret/).
I am following the plans that are available on the mach2 yahoo site, but will email the original author to see if he will allow me to post the drawings here.

So then, to start with, I have purchased a 6"x6"x4" block of cast iron for the body. It weighs around 20-25 pounds, and currently have it chucked on the lathe. I have got as far as facing one side, drilling through, and boring the two holes for the indexing spindle to ride in. As a slight change to the plans, I have bored the bearing hole 1/2" oversize, and I intend to sleeve it with phospor bronze. This is where I am at now....

Kong, looks like an awesome project. Do you have any drawings or design plans you are going off of? I am still getting ideas, maybe some day I will build one, more likely if I was to get a bigger lathe.

Jon

Hi Jon, I am using the plans available from the Mach2 yahoo group files section. Hell, I am even working in imperial measurements! That cast iron is not nice to machine, just figured it would all add to the rigidity of the thing. Just having a break for tea, then I will hopefully get the main piston cylinder bored out.

Hell, I am even working in imperial measurements! That cast iron is not nice to machine, just figured it would all add to the rigidity of the thing.

I hear you about the cast iron, When I served my tool and die apprenticship (many moons ago) we broke a cast iron connecting rod in our 80 ton press. Guess who got the job of making the new one out a block of cast iron about 24 X 16 X 8. Nasty stuff.

kong, cast iron's dampening and dimension stability make it right choice and as you've found it usually works best when machined in imperial units, but what’s going on with the cutting problem? aside from being a pain to clean up, I've always found good CI the nicest of material to machine, once you break through the outer skin that is. Machines easily, easy to get a nice finish, no stringy chips, no messy coolant or oil etc.

kong
mcgyver's right cast iron should cut nice when through the skin
i used to make gravity dies from the stuff, if all you've cut before is ali or m/s
you'll find it a bit different but hopefully satisfying (eventually)
mind you the wife will start moaning when you enter the house looking like a miner
(...or maybe not..;-} )
by the way DON'T USE COOLANT ....low revs and a "brisk" feed.
finally there's something about the imperial unit thing .
maybe it's just me.
mike

Lol guys, I am in the UK, and hence always use metric measurements! I can honestly say I have never machined anything to imperial measurements before!
Don't get me wrong on the cast iron, it is just that I am not setup for this large a piece, I am boring a 4" diameter hole, 3" deep into the iron with a 3/4" boring bar. This is why it is hard work! I usualy machine aluminium with bores upto 2.5", so that is what I am setup for.
I suppose I should do a quick update - the machining is slow on the iron for reasons mentioned above, hoepfully I will get that finnished off this evening. Just got back from the scrap yard on the lookout for bronze or brass for the piston - 4" dia, 1.5" long. Everything there was too big, and since they don't cut it, I would have ended up paying £22 for the closest size piece ($45). I will go look again on Monday. I will get some pictures up of my progress later on tonight :)

Good, that is the boring bit done, boring, eh, eh?!
Nevermind, I will go back to work!

Nice Kong,
heh...now I get to watch you! :)

I am watching this project with baited breath.

Right then, next part! I have made two aluminium plates, bored one to accept a stepper-motor shaft, and have pressed dowel-pins at 4 points around the circumference. The second plate is the same size, and bored 10mm so it can be bolted to the main spindle. It also has holes around the edge, but these are slightly large so it can slide on the dowels.
When the turret is in the locked position, the two plates will be (almost) pressed together. When it is unlocked, the piston will push the spindle forwards, therefore pulling the "floating" plate with it. The dowels will keep the stepper motor connected to this floating plate, and will still be able to turn the main spindle. At the moment, they slide perfectly, but when I get everything assembled, there will probably be some binding. If this is the case, I will have to slot the holes slightly, being careful not to introduce backlash into the system.

Clear as mud eh?!

looking good
mike

Good news, the author of theplans has allowed me to put them up for download.
So it is a big thankyou to Ron Kliewer of Vancouver b.c ;)

I got to the scrapyard again today, picked up a nice piece of stainless for the spindle, and a big block of brass for the piston. I only managed to make the spindle today though, and was pleasantly suprised to see it machined quite easily on the lathe. Using speeds and feeds similar to aluminium, I managed to get a quality surface finnish.
Here's a couple of shots to close ;)

Kong, I am redesigning these in 4" diameter turret for my mini lathe, I am assuming the piston is the part that goes on the larger part of that spindle. Do you know what the reason for it being able to slide is? it slides on the spindle. I am trying to decide how I want to do this and it depends on if this thing needs to slide or not.

Your progress is looking great. I am looking forward to possibly making a 4" turret for myself sometime or another.

Jon

Hi Jon, to be honest, I don't know! It only slides around 0.15", so I am guessing the author was just trying to maximise the amount of air used to actuate the assembly. I would say fixed would be fine. I think that brings up one point though, which I know nothing about - how will the reduced air volume inside your smaller cylinder affect it's clamping pressure?
Since you are in design mode, I would also be interested in your ideas for the main tooling plate. I am looking for a method to adjust the centre height of the tools, and also I would like to be able to have "bolt-on" boring bar holders. I am thinking octagonal plate here. Have you got that far yet?

What I would do if I had more room is mount the turret in the back position, this way you can run the tools upsidedown and always have the same tip height. Because I dont have room for it right now, I will put mine infront.
If I went with a bigger face, I would offset the tools down a little, basicly so the tip is at or below the centerline of the tooling plate.

The Dorian tool manual tool turrets have bolt on things that bolt onto the end of the octagon for boring bars and drills and stuff. I was thinking about doing something like this too, the main problem here is that if you have the bar sticking out the back, you cant rotate all the way around.

This is also similar on the auto tool turret on the powerpath 15 we have at work too, their are tool holders that bolt to the end of the faces similar to the boring tools on the dorian tool turret but are on the face of the turret, the boring holders bolt on the end too.

Jon

The volume of the cylinder shouldn't make a difference on clamping force. Your primary concern with a cylinder is the surface area of the inside face. The volume will make a difference if you have a limited air supply or a very small compressor with no tank.

Richard
www.homemachineshop.com

More stuff! I made the piston today, lovely fit. Even without the O-ring installed, I can hear a little "puff" of air if I move the piston within the cylinder. I will go to the steel shop tomorrow and pick up the main tooling plate.7" diameter I reckon, and I will turn it into an octagon. Should work :)

I would think about making the octagon plate bolt on to a second plate hooked to the piston.

Then slot the holes on octagon plate where it bolts to master. You can then adjust center height later.

This is how most turret's are built on full cnc equipment.

Decided to revise his drawing how I would build it. (keep in mind, designs are like opinions, which are like ....)

http://s94691562.onlinehome.us/albums/album12/aau.jpg

So the yellow plate is permanently fixed, and would lock onto the pins on the cast body right? This way the tooling plate is removable/asdjustable. I guess if I went with this syestem, you could have one plate setup for turning tools, and another for drilling.

Yes in my revised design, yellow is plate that locks down.

Dark grey tooling bolts to it, via slotted holes, adjust it to where it is true, then you could either just tighten down, or tighten and drill/pin.

If anybody is interested I could make full drawings of my design. I do have the solid model all done.

ya ya definitely drawings definitely! if you could give up the solid models that would be awsome too!

If anybody is interested I could make full drawings of my design. I do have the solid model all done.

Very Generous TY1295,

Put me down :)

Thanks
Ken

That is an impressive project. Nice work so far!

nice work.
Looks very similar in design to Okuma's turret on their "Crown Lathe" models.
good luck with your build.

ps, If your dowel pin idea dosn't work out for you consider a "hirth" style gear set for meshing....just a thought.

How do you plan on mounting the turret onto your lathe? I am trying to figure out the best way to mount this for when I make mine if I do make mine.
I could screw in from the bottom, could put toe clamp slots in the side, bolts from top, could make flanges. I am not sure what the best way to do it is.

Jon

nice work.
Looks very similar in design to Okuma's turret on their "Crown Lathe" models.
good luck with your build.

ps, If your dowel pin idea dosn't work out for you consider a "hirth" style gear set for meshing....just a thought.


I agree the dowel pin isn't best method, but is probably easiest for most to build.

Working on drawings for everybody. Keep in mind I haven't built it yet, just adapted and changed a few things based on my cnc experience.

Yep, I looked at hirth couplings first, but the dowel pin method is far cheaper. We will have to wait and see how strong it will be!
Jon, I figured on bolting it to a steel plate from below, then using the steel plate as a flange to bolt it down onto the lathe. At present, I don't know how much material I will need to remove or add in order to mount it on centre.

Kong, a suggestion I have is to remove the material from the steel plate rather than the tool turret, it makes for easier transfer to another machine or adjustment.

Jon

Thanks Jon, point taken, just as long as I have enough thickness in the steel plate for a secure mounting - ie, no good having a 1/8" mounting plate!
And here is a quick update too - all seals in place, and ready for assembly!

And assembled! I expected problems, so I figured on at least one test fit. I have a little binding on the drive plate from the stepper motor to the spindle, so I will have to slot the holes a little. By far the biggest problem I found though, was that the dowels themselves were far too short to reach the spindle drive plate - I never had any longer dowels on hand, so I made a new, thicker drive plate to attatch to the spindle, 0.75" thick as opposed to 0.25" on the original. Now just just gotta sort out that binding, maybe tomorrow;)

Nice job Kong.

Looking good.

I did get my drawings of the very similar design with just a different face plate for those wanting it.

The real design credit should remain with the original author, I just made a few personal tweaks.

www.nwstp.com/jsm/turrett.pdf

I would love to build one, but my time is limited.

Anybody want to build one for me?? :)

Thanks man, and nice plans too......just a quick comment though, in the left photo in my previous post you will notice a register on the front of the iron block. The mounting plate must go over this to minimize swarf collecting behind the plate. Without it, swarf can get into the groove behind the main spindle and will eventually cause problems. Hope you have time to work this into the plans;)

in the left photo in my previous post you will notice a register on the front of the iron block. The mounting plate must go over this to minimize swarf collecting behind the plate. Without it, swarf can get into the groove behind the main spindle and will eventually cause problems. Hope you have time to work this into the plans;)


Not following you yet.

You saying between the yellow piece and the main housing?

That is looking awesome! Do you plan on machining the outside of the CI block to make it look all nice?

I was thinking about putting the O-ring grooves on the shaft too, wasnt quite sure if I wanted to or not becuase the seal would be moving too.

It looks good.

Jon

Yeah, either the yellow plate could cover some sort of raised section, or if the front tooling plate overlapped the whole lot (yellow plate AND register) then it would stop the swarf. Look again at the picture on the left and check out the gap between the spindle nose and the iron block. Not much, but could cause problems.
edit - Thanks Jon, yep, I would like to get it all painted up too, so it looks professional! I have no miller yet though, but hopefully it will be delivered on Monday so I can get the thing finnished off.

Quick update for you, I got bored over the weekend and decided to install the pins and the front plate. I have taken the idea from ty1295 and used a secondary plate that is permanently attatched to the main spindle, and so I can have a removable tooling plate which can be adjusted easily afterwards. The dowels were a nightmare to get in since I never had the correct size reamer on hand, the press fit was tight, and I almost did myself an injury squashing the assembly in the vice! The pins did need some grinding afterwards since there were a couple of them that never made it squarely into their holes, but the fit I have achieved is completely rigid. Once I get the milling machine, I can build the front plate, so it just a case of waiting now!
I realise that the brass is not the best material for this job, but it can be replaced easy enough, and for the amount of turning I do, it should last me quite some time. The other thing I need to do is hook up the air supply, then I can get some shots of the pins themselves. The plate comes off easily with the back off, but when it is place (like now) the airlock is very strong.

If you want to get tricky, when you install the tool plate load the endmill in the chuck.

Then use the crossslide to machine the slots.

boring bars, etc could be loaded up for boring a hole, drilling, etc.

Be interested to see how it works for you when done, and any things you would change further.

I haven't gotten to update my drawings yet, for the recess though.

....just waiting for the next post updating this project....
Nice, Kong!

Lol, I haven't abandoned it. just got busy building a koi pond. I have the miller all up and running now, so once I get the time......you know how it is!

And we want video of it operation when it is completed ;)

Hoorah, finally I have some time to complete the turret.

I picked up a 6" x 2" disc of chrome-molly (EN24T) steel for the toolholder. The disc was bored at the rear to fit tightly over the brass face-plate, then I cut some flats on the circumference which were supposed to be for the boring bar holders. Buggered that up though, so I will have another go at that tomorrow!

Got the thing mounted though, it is bolted to a steel plate from beneath, then the plate is bolted to the rear of the cross-slide. I am just cutting the slots for the tools using an end mill in the lathe. It will have to come off again though since I don't a cutter big enough to cut all of the slots I need :(

Electronics and pneumatics hopefully tomorrow...

Thanks for the update Kong. WIll be interesting to hear you experiences once you havethis in service. Do you regularly have runs of parts to make? I find I use my CNC lathe for lots of one offs, so the AXA tooling changed manually is nota big deal.

Yeah, I make RC car alloy wheels. Generally, I use 2 or 3 tools per program so the tool change is a PITA. This will certainly alow me to get more adventurous with my designs.

Well I managed most of the wiring over the weekend, but it turns out my step-motor driver was garbage. I have just ordered a replacement which should deliver full torque to the turret.

Cut the slots today for the tools, I roughed them out on the lathe to get the centres, then finnished on the mill. Slow going, just got the boring bar holders to make now!

i look forward to seeing the final solution to this project. keep up the good work.

Well, almost there! I have the boring-bar holders made, and drilled them on the lathe. Still need to drill and tap for some securing bolts though, oh yeah, and chop off my bars so they don't hit the body of the beast :(

Got the pneumatics all hooked up and under Mach3 control now, but there is a very slight air leak when the turret is closed. Seems to be coming from the main spindle, so I will wip that out tomorrow and replace the o-ring.

Almost had the stepper working today.....Got the new drive from www.routoutcnc.co.uk and got it all hooked up, fired up the stepper, then proceeded to unbolt it due to a slight amount of binding. Being a clutz, I dropped the stepper and somehow managed to blow the board! Never mind, a quick phone call to Mike and a new one is on its way - not free, but since I can't wait for him to fix the broken board, I got a nice discount. Thanks man ;)

Looking good, how are the boring bars held in the tool post?

EDIT: ok apparently i can't read, as you clearly stated you need to still drill and tap :rolleyes:

Kong,
I have thoroughly enjoyed watching your progress, thanks for taking the time to post the results.

We are rootin for ya :D


Ken

Right guys, time to ask for your help!

As you can see, I am using a piece of 1/4" CRS which is tapped to receive 3x 1/4" hex bolts to hold the tools in place. The problem is that I cannot work out how to hold the parting toolholder usingthis method. Any ideas? Just not enough room to get the spanner in top tighten the bolts :(

Apart from that, the stepper motor was junk. I thought thee was binding within the system which was causingthe stepper to stall. It turns out the stepper was faulty and even when I disconnected it from the mechanicals, it still stalled itself. Another one is on order, but I have also gone for a slightly larger motor at 300 oz/in holding torque. Pneumatics are working great, and I will have a go at some test cuts tomorrow....providing I can get that part-off tool installed!

Just a thought, not sure if might help or not.

You could drill and tap the face of the turret inside the tool slot. Then, remove the blade from your parting tool holder. Drill and c-bore a pair of matching holes in the parting tool holder with the ones on the turret face.

Install some cap screws - re-install your blade and you may be ready to go. I don't know if this will give the tool enough support though. The clamping force would be along wrong direction, but it may be worth a "look and see".

Chris

Kong, if you ever redo the tool holder plate, make it so the screws push down on the bottom of the tool, this way you always, regaurdless of the tool size, have it right on center.

That whole setup is looking pretty decent, did you get the leak fixed?

Jon

Thanks Jon, I just made it "this way" so I could find the centres using an end mill in the chuck. I see what you mean though, I guess I was just being lazy ;) Another pointer would be to cut the slots a fair bit off centre so the tools don't all end up touching one another in the middle. I had to chop the end off of my big grooving tool to get it to fit :(

Yeah, the leak was just a sheared o-ring where the fit was a bit tight. All fixed now.
As a temporary measure, I have removed the stepper, and thrown a large piece of rubber over the hole. At least I can have a go with it tomorrow.

To lock that parting tool, how about making a pair of tapers and inserting them from the end, then expanding them against each other to lock. Like a tapered gibb for a lathe saddle.

http://warhammer.mcc.virginia.edu/ty/7x10/vault/Lathes/7x10-7x12-Projects/TaperedSaddleGibs/

:wee: I will get onto it!

Well I have the tapers made, and they work perfectly. Still got problems though, the new stepper was fitted today, and is still not powerful enough :( I am seriously considering using a worm gear now, but I will go and play a bit more first!

How is the turet working??

How well do the locking pins keep it ridged? How my cycles do you think you will get before any slop?
Thanks for documenting your progress. It sure helps give one confidence on undertaking a project like this.

Donny

hi all where can i find the 4" oring been looking everywhere

You can get them here
http://www1.mscdirect.com/CGI/N2DRVSH

Or purchase splicing kits to make them your self as well, it's easy.
http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1797541&PMT4NO=0

Kong,

It looks like a great project. Seems to me you need a good macro to run the tool change process. Enclosed find the one I use with Mach3. I think you can use this one, or get ideas to make your own. I use M10 to unlock the turret and M11 to lock the turret. Could atach those macros if you need them.

Arturo

Enclosed find the macro, forgot to upload last time.
Arturo

Hi Kong

Just finished reading all about your building the Revolver for your CNC Lathe. Excellent job. I am planning to either convert a small Lathe to CNC or possibly build my own from scratch. This Revolver would be a great addition for any CNC Lathe project. I was originally thinking of using Gang Tooling but you are so restrictive and cannot use a Tail Stock.

Question:
In your opinion which is the best all around position for a Revolver? Front or rear of the Chuck center line? I understand that this depends allot on the type of Lathe you are installing it on but if you happened to be building your own Lathe design and could have it either way, what would you pick? Things to consider: (1) Easiest to see cutting tool while machining. (2) Best for controlling Swarf flying around.

Thanks for your help.

Willy

hi all
how can u oprate with ur pc software or in witch software?
moghul

It is used with Mach3 cnc controller software.
http://machsupport.com/artsoft/index/index.htm

I've been checking the drawings and have been reading this thread, but I'm maybe stupid as I can't really get it. How is the turret locking up between tool changes? You're not hanging entirely on the stepper, are you?

--S

Ah, got it at the linked web page, the magic is air... :)

You have to keep the turret locked. My lathe has a pneumatic solenoid valve that I activate with a relay. The pneumatic piston holds the turret in position while the tool is cutting.

Arturo Duncan
http://cnc4pc.com
http://cnc4pc.com/Live_Help.htm

i want to thread cutting on cnc lathe n mach2 . how can i do this? what type of encoder or feedback will be use for spindle?
shabbir moghul

Moghul,

This is what you need ofr threading with a lathe: http://www.cnc4pc.com/Store/osc/product_info.php?products_id=129

Thanks,

Arturo Duncan
http://cnc4pc.com
http://cnc4pc.com/Live_Help.htm