ER chuck collet

[Road_Clam]

I bought a cheap china er32 straight shank holder to experiment with. Did not have high expectations of precision. I was no disappointed. Im seeing about .008" tir. I can correct this by holding in a 4 jaw and indicating but im not sure what collet style i ultimately want to go with . Im also thinking of a 5c setup for more stock diameter capacity.

 

[BGHansen]

Check out the comments from davidpbest in the thread below. He left a post about the advantage of ER collets over 5C. A number of things favor ER's over 5C. One off the top of my head is 5C's only grip at the tip of the collet while ER's grip at two axial rings (more stable). Fewer collets needed for ER's for a full range. RJSakowski has a nice drawing explaining 5C clamping in the same thread.

I have 5C's at two lathes from 1/16" to 1 1/8" by 1/64". Most of the collets will never be used, bought the full set just in case (times 2). Had I to do it all over again, I'd look long and hard at an ER collet chuck. I have an ER40 collet chuck on my Bridgeport which saves me from reaching up for the drawbar (unless throwing on an R8 arbor tool). Also have many ER tool holders for my Tormach.

Bruce

35 vs 72 piece Collet set?

Need a complete collet set and looking at these: https://www.precisionmatthews.com/shop/72-pc-precision-inch-5-c-collet-set-164-to-1-18/ I know twice as many is twice as good - it's also twice the cost and twice the space in my shop. There's not much info on the site - does anyone know the...

www.hobby-machinist.com

 

[T Bredehoft]

...when cutting metric threads when using the transposing gears, you need to back the cutter off and reverse the motor to back the carriage up...

I found that I could (running low RPM on a fair sized (diameter) piece) apply a crank handle on the left end of the spindle and hand crank it back to position easier than reversing the motor. Yes, without dis-engaging the gear train.

 

[Chris Hamel]

I have an 11 inch Logan and am curious whether a transposing gear exists for my lathe. Did you swap out one of the existing gears? Can you post a picture showing the gear in place.

 

[mickri]

Halligan142 did a video on making an ER collet chuck. He went through the math to determine what gears were needed to cut the 1.50mm thread on his south bend lathe. The math should work for your logan lathe. You would need to use the gears on your logan lathe.

For a logan lathe these may help. http://www.lathe.com/tips/met-thd.htm http://www.lathe.com/metric_threading.htm

 

[woodchucker]

Halligan142 did a video on making an ER collet chuck. He went through the math to determine what gears were needed to cut the 1.50mm thread on his south bend lathe. The math should work for your logan lathe. You would need to use the gears on your logan lathe.

For a logan lathe these may help. http://www.lathe.com/tips/met-thd.htm http://www.lathe.com/metric_threading.htm

I think that is his best video.

 

[Chris Hamel]

Thanks for the info. I was always curious how to set up to cut metric threads. Not sure it is worth it since I have a friend with an Enco lathe that will cut metric threads should the need arise.

 

[phubbman]

This is the gearing setup I used on my 10” Logan lathe to cut 1.5mm threads. It worked perfectly.

 

[Shotgun]

My Sebastian doesn't have that slot for sliding gears back and forth to set spacing.