Er25 Collet Chuck For Atlas 618

[mattthemuppet2]

thought this might be useful, especially with an extra special ingredient - hex stock for the chuck body! That way I can also use it to cut flats on the mill

This was partly inspired by the one on deans photographica website, which is a rich source of project info. Especially useful were the gears needed to cut a 1.5mm pitch thread. http://www.deansphotographica.com/machining/atlas/ER25/ER25.html

stock left over from cutting of the piece I needed

sawn end faced off. Lots of really light cuts with this much stick out and interrupted cuts
spindle hole drilled and bored out, with spindle register and threading relief (you can just see it at the back) cut ready for threading

threading done I'm still amazed when this works out!

 

[mattthemuppet2]

the spindle nose copy I made for my 4 jaw back plate was really useful here - this was only the 2nd test fit and it went on very smoothly

threaded onto the spindle

The cap end rough turned round. I'll turn it to the thread OD and cut the relief later today. I'm on a mission - prep for next semester starts in earnest on Monday plus 2 job applications due then too!

 

[kd4gij]

Looking good so far.

 

[mattthemuppet2]

thanks man! Making good progress so far and fingers crossed the rest will go smoothly

 

[mattthemuppet2]

Cut to the thread OD and relief for the collet nut

32x1.5mm thread cut

nut threads on smoothly the whole way Those dings in the body will get filed off when I'm finished.


drilled out to 5/8in and then bored to 0.7in - a bit larger than the ID of the largest collet (16mm)

compound set to 82deg (ER collets have a 16deg included angle or 8deg per side) and the mouth bored out. I was having trouble getting good readings from the collet about the angle last night plus it was 18F in there, so I left the final finish cuts/ grinding for today. I have plenty of thread and throat depth to play with though, so I'm not too worried about taking more cuts.

 

[JimDawson]

Looking good Matt!

 

[mattthemuppet2]

thanks Jim! It's the taper step that's making me worried - I wish I had some of that high spot paste that Dean used as a sharpie isn't quite cutting it.

 

[Andre]

Get some oil paint from the art supply store, works great for high spot printing.

Nice work so far!

 

[mattthemuppet2]

ooh, that's a great idea Andre, thanks! We have tons of art supplies just under the futon I'm sitting on, so I'm sure I'd be able to find something suitable

 

[David S]

Nice work Matt. I also have a 618 and may put this on the "to do list". I all ready have the ER collets with the MT2 arbor, but it would be nice to be able to put longer pieces through the spindle.

Perhaps you could also put a link in the Atlas Lathe forum.

David