ER 32 Collet Chuck for SB 9"

[stevec]

(12-11-2013, 08:10 AM)marfaguy Wrote: Yep. That's how mine works. If I just let it very lightly touch the back it will register about .001 out. With just a bit of snugging it settles out to less than .005 every time.

Marf, can we assume you meant "it settles out to less than .0005 every time"?

[Shawn]

Cool thanks Marafaguy, I won't mess with mine then, good to know.

Shawn

[marfaguy]

(12-11-2013, 11:53 AM)stevec Wrote:

(12-11-2013, 08:10 AM)marfaguy Wrote: Yep. That's how mine works. If I just let it very lightly touch the back it will register about .001 out. With just a bit of snugging it settles out to less than .005 every time.

Marf, can we assume you meant "it settles out to less than .0005 every time"?

In the immortal words of Homer Simpson...DOH!! Yes I mean't .0005"

[Shawn]

Almost there, just have to bore out the tapered hole.



Shawn

[stevec]

Shawn, have you a plan for how you will bore the taper for the collets?

[Shawn]

I was going to dial in the compound slide to the internal bore on the ER32 collet chuck I have mounted to a MT3 taper. I set it up last night but will need to fine tune it today. I did remember to set the dial test indicator as close to centre height as I could manage. When I get close I will test the bore with a ridgid collet and some layout dye. Hopefully that will work? I have a fair bit of work into it now, I would hate to turn it into a paperweight.

Shawn

[Shawn]

Well I got the collet chuck finished this afternoon, cutting the taper was a relatively simple task, dialling in the compound was a slightly different story that took me awhile. I finally had to estimate the amount the compound would move as I tightened the two locking screws.





I'm not exactly sure what would be considered acceptable runout? Until I get an accurate test bar of some sort I just made do with and edge finder.





Shawn

[EdK]

Shawn,

That doesn't look too bad. Do you have a DTI? That would be a better tool for the job. Also, try removing and rechucking the edge finder to see how repeatable it is.

Ed

[f350ca]

Looks pretty good Shawn, well dun. I can't get the 5C collet chuck on my well used Colchester to run any better.
Your edge finder is probably ground round and straight.

[Shawn]

I tested the runout again tonight with an Interapid DTI and got pretty much the same results. Repeat ability seems good though and the bore measures less than .0005 runout so I'm going to blame it on the cheap collets I'm using It is much better than my three jaw chuck though and I think its going to get a lot of use. The depth of the bore turned out to be fine, I was measuring the full length of the collet and not thinking that there is a small portion that protrudes out of the chuck to allow it to be tightened down. All in all I'm pretty happy with the final results and I think it looks bad a$$ on the lathe.



Shawn