Shars 5" ER40 Zero Set Fine Adjustment Collet Chuck

[T Bredehoft]

I, too, saw this thread a few months ago, ordered one to use on my (at that time not yet delivered) PM 10-30 Lathe. In the process of mounting it on the appropriate backing plate I incorporated a screw-in adjustable part stop for short pieces.

 

[diamond]

So to follow up I did end up getting the Shars adjustable ER40 and their D1-4 backplate. Today I set it up on my PM 1340gt. I followed the advice of another (deleted?) member in this thread: https://www.hobby-machinist.com/threads/shars-er40-chuck-on-a-pm1340gt.68998/

The short story, I'm extremely pleased. Thank you Mark Jacobs for originally posting about it.

Skim cutting the back plate was very messy. I've never machined cast before. No chips, just black dust everywhere. Yuck. Perhaps that's my inexperience, was using a carbide insert and 1100 rpm. Tried slower but didn't like the finish. Even that didn't turn out to be a mirror but it is nice and true.

Once that was done, I mounted up the chuck and dialed it in. Was able to get it down to less than 0.0002 runout on a Mitutoyo dial indicator. Honestly it's probably ~0.0001. Needle hardly moves. Was very easy to dial in. I didn't take it off the spindle and remount it to see how it holds.

After machining the backplate:


With the chuck installed:


With a bearing nut & a test cut. This is going to be SO much nicer for small parts.


Since I do use my compound I really don't need more stick out. This seems to be plenty.