CNC lathe 5C spindle build

[Bob La Londe]

I think 7075 machines easier than 60 61.

[aarongough]

I think 7075 machines easier than 60 61.

I requested a quote from my metal supplier for 7075 a while ago, and their price was like 8 times more than they charge me for 6061-T6!

That's the only thing that's stopped me from trying it. If I could get it at a reasonable price I would definitely try it.

[mactec54]

aarongough

For machining 12L14 is best if you want to use steel for your parts, if you want to use stainless steel 303 or 416 is best, This is mostly what I use, the body can be any thing you want to use, but the better grades of alumumin are stronger as well as a little easier to machine, cast iron is the best, but messy to work with, the benefits are worth it though

[aarongough]

aarongough

For machining 12L14 is best if you want to use steel for your parts, if you want to use stainless steel 303 or 416 is best, This is mostly what I use, the body can be any thing you want to use, but the better grades of alumumin are stronger as well as a little easier to machine, cast iron is the best, but messy to work with, the benefits are worth it though

I've used 12L14 in the past, and found it nice to work with (except the surface finish).

I had *assumed* that 12L14 would be much more expensive than CRS. I called my supplier back on the off-chance and it turns out that they have it for *less* than the CRS!

Well, you know what they say about assumptions!

Thanks for mentioning that, otherwise my assumption would have gone un-checked and I would have been wading through CRS rather than enjoying short-chipping glory!

[aarongough]

Picked up the materials for the spindle and headstock today. The block of aluminum came in at 6x6x6".

It also turned out that they had more than enough CD1144 in their 'scrap' room to cover the entire build... wish I had known that before I ordered the 12L14 as I would have saved a lot of money!

Anyway, I'll be starting on the spindle-mounted parts on Saturday! Looking forward to it!

[aarongough]

My plan was to do the boring of the headstock on the lathe, but looking at the stock I think that might be a bit ambitious/unsafe. Any thoughts?

I have a 6-1/2" 4 jaw chuck for the lathe.

I don't have a boring head for the mill yet, but I can get one if it's agreed that's the best way to tackle the boring.

[aarongough]

OK!

Just ordered all the bearings, including a very nice set of Barden matched A/C bearings that Lakeside pointed out earlier!

I'll be making a boring head for my milling machine this weekend as well, then once the bearings get here I'll be ready to get cracking!

[aarongough]

Progress!

I had a bit of time last night to spend in the workshop, and I got started on the bearing retainer nut.

I used the CD1144 rather than the 12L14 as I've used 12L before and I wanted to see what the CD1144 was like. Beautiful stuff to machine! I'm running it a little slower than I likely should because I'm only just getting used to my new lathe, but I don't even have to try to get good surfaces and nice chips, it just happens!

I'm using carbide tooling at the moment, but I get the feeling this stuff would turn even nicer with HSS and a larger tip radius. The next part I will try HSS tooling and see how it goes.

I don't have a depth micrometer, so all the step measurements are being taken with calipers. I'm taking my time and double checking to make sure I don't screw something up, and so far so good! I also found out rather too late that I don't have any boring tools to fit the new lathe, for some reason I thought my old tooling would fit but it's not even close. All the boring so far has been done with regular turning tools held at 45º to the face of the work, that's actually been working very well so far! less finicky to setup than round boring bars. Obviously it requires a lot more clearance though...

I will finish off the retaining nut today and get started on the first element of the labyrinth seal...

[Bob La Londe]

Sorry, I must have missed it. Did you fially decide to go with sealed bearings or oil splash oil?

[aarongough]

Sorry, I must have missed it. Did you fially decide to go with sealed bearings or oil splash oil?

Hey Bob,
In the end I decided to use grease-lubricated A/C bearings with a separate labyrinth seal at the nose that I am fabricating.

-Aaron

[aarongough]

Unfortunately I just scrapped a part due to what seems to be a problem with my lathe.

The lathe is a Grizzly G0602, manual lathe with a partial threading gearbox.

I have the lathe setup to cut 32TPI threads, but for some reason it is cutting something like 34 or 35 TPI threads... My thread gage says it's not 32TPI and it's also not 36TPI.

I've checked the setup multiple times, even counted the teeth on all the gears to make sure they weren't mis-labeled at the factory.

The setup for taking the cut:
- swap the change gears to the ones indicated on the chart
- set the gearbox to the positions indicated on the chart
- align the thread insert on the centerline of the part, and perpendicular to it
- touch the tool off on the OD of the part, then back away
- move the carriage to the right of the part
- touch the thread dial to the leadscrew
- fire up the lathe
- wait until the thread dial reads '1'
- engage the half-nut
- take the cut
- disengage the half-nut
- move the carriage to the right of the part
- wait until the thread dial reads the same number
- repeat

It's not cutting overlapping threads on anything, just the thread pitch is wrong. The pitch I'm getting is not like anything listed on the thread chart.

This is really ruining my day, any suggestions?

[Bubba]

By any chance you have a metric lead screw????

[Bob La Londe]

Unfortunately I just scrapped a part due to what seems to be a problem with my lathe.

The lathe is a Grizzly G0602, manual lathe with a partial threading gearbox.

I have the lathe setup to cut 32TPI threads, but for some reason it is cutting something like 34 or 35 TPI threads... My thread gage says it's not 32TPI and it's also not 36TPI.

I've checked the setup multiple times, even counted the teeth on all the gears to make sure they weren't mis-labeled at the factory.

The setup for taking the cut:
- swap the change gears to the ones indicated on the chart
- set the gearbox to the positions indicated on the chart
- align the thread insert on the centerline of the part, and perpendicular to it
- touch the tool off on the OD of the part, then back away
- move the carriage to the right of the part
- touch the thread dial to the leadscrew
- fire up the lathe
- wait until the thread dial reads '1'
- engage the half-nut
- take the cut
- disengage the half-nut
- move the carriage to the right of the part
- wait until the thread dial reads the same number
- repeat

It's not cutting overlapping threads on anything, just the thread pitch is wrong. The pitch I'm getting is not like anything listed on the thread chart.

This is really ruining my day, any suggestions?

My first thought when I get an odd ball is to double check I am not cuttin a metric thread that is close instead.

Make both parts 34.X TPI? If you are making both parts does it really matter what thread they are as long as they are the same?

I would drop a line to Grizzly and ask them, also see if there are any Grizzly specific lathe groups where you might get some feedback sooner. Is it possible you got the right gears, but Grizzly sent you the wrong lead screw, clamp nut, etc? I think I recall reading something like that before.

By any chance you have a metric lead screw????

We must have been typing at the same time. LOL. Is this Bubba from the CB forum?

[aarongough]

By any chance you have a metric lead screw????

My thread gage says the leadscrew is 12TPI, that was my initial thought as will... In which case I would have pitched a fit at the company I bought it from (King Canada).

[aarongough]

My first thought when I get an odd ball is to double check I am not cuttin a metric thread that is close instead.

Make both parts 34.X TPI? If you are making both parts does it really matter what thread they are as long as they are the same?

I would drop a line to Grizzly and ask them, also see if there are any Grizzly specific lathe groups where you might get some feedback sooner. Is it possible you got the right gears, but Grizzly sent you the wrong lead screw, clamp nut, etc? I think I recall reading something like that before.



We must have been typing at the same time. LOL. Is this Bubba from the CB forum?

Hey Bob!
I should have thought to measure them more closely and see what I was getting. Here's the info:

7 threads = 0.413"
That's 0.059" thread pitch.

1 / 0.059 = 16.949 TPI (???)

Interestingly the 0.059" thread pitch is 1.497mm, very close to 1.5mm thread pitch.

I really want to pitch this lathe over the hill right now.

[aarongough]

My first thought when I get an odd ball is to double check I am not cuttin a metric thread that is close instead.

Make both parts 34.X TPI? If you are making both parts does it really matter what thread they are as long as they are the same?

I would drop a line to Grizzly and ask them, also see if there are any Grizzly specific lathe groups where you might get some feedback sooner. Is it possible you got the right gears, but Grizzly sent you the wrong lead screw, clamp nut, etc? I think I recall reading something like that before.



We must have been typing at the same time. LOL. Is this Bubba from the CB forum?

The lathe is the King Canada version of the G0602 by the way, identical as far as I can tell.

If I could do it over though, I would buy a grizzly instead. The manual that King supplies is a laughable 6 pages, and is actually wrong in several cases! eg: it says the spindle has left-hand threads when it does not.

The grizzly manual is far better, and also nearly 60 pages long!

[Bob La Londe]

Hey Bob!
I should have thought to measure them more closely and see what I was getting. Here's the info:

7 threads = 0.413"
That's 0.059" thread pitch.

1 / 0.059 = 16.949 TPI (???)

Interestingly the 0.059" thread pitch is 1.497mm, very close to 1.5mm thread pitch.

I really want to pitch this lathe over the hill right now.

I can understand your frustration. I have an old 8.5 x 18 that is much more stout than my 7x10, but the gears it says to use for some threads can not physical reach each other. LOL.

So tell me which hill. I'll park my truck at the bottom. With some luck it will land in the bed and I won't even have to use the bed crane.

[aarongough]

I can understand your frustration. I have an old 8.5 x 18 that is much more stout than my 7x10, but the gears it says to use for some threads can not physical reach each other. LOL.

So tell me which hill. I'll park my truck at the bottom. With some luck it will land in the bed and I won't even have to use the bed crane.

The annoying part is that I went with King rather than another company in order to avoid exactly this sort of problem, and paid extra for the privilege.

I'm going to try another change-gear setup to get the 32 TPI threads and see if that helps. Unfortunately one of the change gears is retained by an e-clip, not sure who thought that was a good idea.

If I could swap you for a working lathe, right now I'd probably go for it.

[Bob La Londe]

See if somebody in this group can help you more specifically.

10x22grizzlyandthelike : 10x22 lathe

Looks like membership requires manual approval, but it might be worth it.

[aarongough]

See if somebody in this group can help you more specifically.

10x22grizzlyandthelike : 10x22 lathe

Looks like membership requires manual approval, but it might be worth it.

I'll have a look there in a few minutes. Right now I'm calling King Canada and seeing what they have to say. They had better say something useful...