Collet systems for lathes

[BillH]

I have a Lathemaster 5c collet chuck on my 8x14. It has a zero set backplate and I can get it within .0002. I need to bolt down my lathe however as it wobbles and I am positive that affects my ability properly "zero it in". Anyhow, the 5c Collet chuck for 269$ is a great value, it is very nice. It does however have a lot of overhang.
The ideal solution is to mount the collet inside of the spindle, with small lathes that means a 3c collet.

 

[rake60]

The only other issue I can see is that nobody has mentioned whether this adapter is being used with a drawbar or not. It MUST be used with a drawbar. Unless you like having adapters flying around your head at high speeds!

Andrew

A very important thing to note!
The collet holder that I bought to use as a makeshift collet chuck, has a 1/2"-13
thread in the back end. I use a 9" long piece of 1/2"-13 all thread rod as a drawbar.

A regular hex nut would be a safer choice over the wing nut that I use.
There would be less chance of making accidental contact with it.

Rick

 

[Noitoen]

Hi,

Since you have that colet holder, check here. I think it's not difficult to build a chuck. Check here for ideas. http://www.optimum-machines.com/fil...laeuterungen/GB/accessories_turning_GB_08.pdf

 

[Paula]

I have seen pictures of one called a "Loop Collet Chuck", and a fellow by the name of Andy sells a kit, I think it's "Metal Lathe Accessories". I have a boring head I bought from him, very nice fellow to deal with and the castings and drawings were very good.

I liked the looks of the "Loop", and so I made this one similar to it. I'm not certain how the innards are on the "Loop"; but from looking at the pictures, he managed to reduce the overhang a good bit from what I ended up with.

Hi Kevin,

I've got the MLA-21 Loop 5C collet chuck on my short list of projects to undertake. In fact, I already have a set of original South Bend 5C collets (1/16" to 1" by 16ths), so I'm champing at the bit to get started. I've already built the MLA quick-change toolpost, and right now I'm working on the T-slotted cross slide, soon to be followed by the T-slotted face plate.

I like your design (reminds me of a space capsule ), and as you say, the big advantage of making your own is that you true up the collet taper on the lathe on which it will be used, so runout is almost nil. The MLA design may have a bit less overhang, but also less "working depth", as a direct consequence (for stock that won't pass thru the spindle).

Here are some pictures that give a better idea of the MLA design. The "nut" is retained by ball bearings riding in semi-circular races in the nose and backplate:

Paula

 

[steamer]

I have the Bison 5C that I bought years ago for the 10" Atlas.
When I sold the Atlas and got the Logan, the chuck stayed behind. Good thing as it is now mounted on the Logan. I had a extra Logan back plate so I modified the Atlas back plate to mount to it and become "adjust true". I love it and I use it all the time.
The Bison chuck is very high quality and I can't speak more highly of it. I use Lyndex collets and their quaility is excellent also. I recently checked the runout on a 3/8 collet with a part in it and it was less than .0002"....I couldn't ask for better.

 

[S.D.L.]

"The brits have access to a sweet setup that puts an ER-32 nose on a 5C collet."

That would be really nice to have. I haven't seen one but I will keep my eyes out for one.

Dave

Get them here.

http://www.arceurotrade.co.uk/Catalogue/Collets/5C-Fixtures

Scroll to bottom of page.

Steve Larner

 

[joeby]

Paula,

Thanks for the photos, I can see now how shortening the overhang was accomplished. As I mentioned earlier, I had only ever seen the chuck in a picture, and started from there. I see the backplate is much thinner than mine and has a flat front face where the nut would be on the bearing balls. I made mine with a raised ring outboard from the bearing race to act as a sort of labyrinth seal to prevent chips from getting into the bearings.

When I get a chance, I will take a couple of photos of mine if you are interested.

By the way, are those photos of your chuck? If so, it looks like you have a good start.

Kevin

 

[steamer]

SDL


Thanks!
Price is not too bad I think.....I'll ponder that a bit.

Dave

 

[Paula]

When I get a chance, I will take a couple of photos of mine if you are interested.

By the way, are those photos of your chuck? If so, it looks like you have a good start.

Kevin

Yes, Kevin, I would definitely be interested in seeing some pictures of your 5C chuck (as I'm sure others would). The disassembled MLA chuck in the pictures I posted was made by John Wagner, over on the SouthBend10K yahoo forum. It does look like he did a very nice job on it.

Paula

 

[joeby]

I took a few photos of my 5-C collet chuck this morning.

You can tell how much longer it is than the Loop Chuck.

The Loop Chuck design has the backing plate flat and much thinner than mine, and the nut is counterbored on the front, instead of the back.

Here you can see how little clearance I left between the nut and the nose-piece bore, that and the raised ring on the backing plate being a very close fit in the nut counterbore were intended to keep dirt and chips out of the bearings. It seems to have done the job so far.

Kevin

 

[Paula]

Great job on the collet chuck, Kevin!

Your workmanship is first class, to say nothing of your design skills. :bow: You used no castings, right?

Thanks for posting the pictures!

Paula

 

[steamer]

NICELY done!

That was a good bit of work!

Dave

 

[joeby]

Thanks for the compliments!

Paula, no, no castings in this at all. The nose was made of a piece of 4140 round that was a leftover from another job. The backing plate was a bar end from who-knows-what; it turned really nicely, like 12L14, but doesn't have the rusting issues like I would expect. The nut was a piece of 1018. Quite a mixture of materials; but when I started making it, what I had on hand was going to have to work.

Steamer, yes, a pile of material had to come off; but I cheated there just a bit. The bulk was removed by using some spare minutes on lunch break! I took the pieces into work with me and used the 14x40 lathe to hog off most, and finished it on my Atlas.

I think I may have drug this thread too far off Smoggy's intended line; but for what it's worth, if you have the time, a 5-C setup like this works very well, the collets are not overly expensive, and in my case, the material costs were next to nothing (I had to buy bearing balls). The biggest drawbacks of it are the lack of range of the 5-C collet, and the fact that the collet stop is in the collet itself (doesn't necessarily have to be though).

Kevin

 

[steamer]

Ahhh good!

4140 can be a bit nasty to rough without a brute machine.

I know my Atlas didn't like it much.....you had to "ask nice"

Dave

 

[Kermit]

I don't know that I would EVER be able to make something like that! Lord knows I Want Too.

If only I had made it this far twenty years ago. :-\ Oh well, enough of the pity party. I'm gonna try hard and pester your friendly butts to death when I have a problem, and then, and then, uh? I got it! I can do like the AMerican Gubmint. I'll just throw money at it till it turns out like I want!

;D

That is some fine workmanship, but so far as my QC eyes can tell, so is most everything on here. Better quality pictures would only reveal better workmanship I fear. What is going to be hardest will be NOT using my own QC skills and history with parts to judge my first creations. I know my first efforts are gonna suck but I can't let that get me down.

Slave to mystical standards and unreachable tolerances,
Kermit

 

[mklotz]

Kermit,

It's far more important to make something than it is to make something perfectly.

Learn to gauge the quality of your work by what you learned from making it.

If you fall into the trap of "I can't start working until I'm ready to do it perfectly" you'll never get anything done.

Ok, enough pseudo-wisdom from the sage in the cave on the mountain, now get out there and make some chips!

 

[joeby]

Kermit,

Marv won't steer you wrong. We all start somewhere. One other thing to keep in mind is how the particular feature that you're working on functions (cosmetic or critical), if it's cosmetic, tolerances are less of a nuisance.

I work on injection molds for a paycheck, and one of the most aggravating things is to try and hold the +- .0002" tolerance on a part only to find out the part it makes has a +- .015" tolerance on it.

If the function of the part doesn't require "perfect" don't waste time to make it so, make it work instead.

Kevin

 

[steamer]

Get them here.

http://www.arceurotrade.co.uk/Catalogue/Collets/5C-Fixtures

Scroll to bottom of page.

Steve Larner

In retrospect, Instead of the above, I think I'll make up a 5C adapter that has a spindle nose to match my small mill. (M22 x 2 thread with a register diameter) so that I can swap a small chuck between the two machines.....thus keeping the number of different tooling systems to a minumum. I think that would be more useful to me at the moment. Thanks anyway S.D.L.

Dave


Kermit, the best way to learn is to do. Do an appropriate amount of planning then " have at it."
There will be bumps in the road, you will get by them.

 

[SmoggyTurnip]

I think I may have drug this thread too far off Smoggy's intended line;

The original poster is loving it. I would love to build something like that. I dont suppose you have any drawings?

 

[joeby]

Smoggy,

I need to do some more looking. I have the solid model on my laptop; but I don't see the 2D drawings. If I don't find them soon, I will make a new set.

Kevin