collet chuck size

talkingmonkey

Active User
Registered
Joined
Dec 31, 2011
Messages
92
My lathe came with a Hardinge-Sjogren 1A speed chuck but no collets. Does anyone know what size collets this chuck uses? It also came with several Neal Skokie collets labeled 3AT and what I believe is the drawbar but nothing to go on the spindle which is 1.5 x 8.

Thanks,

Jeff
 
Thanks Jim,

According to a chart from Logan, link provided below, they are nearly identical thread diameters (3AT 0.637 vs. 3C 0.640) with both being 26 t.p.i.. The overall length being slightly different ( 3AT 2.313 vs. 3C 2.688). This 0.375 difference "seems" negligible given the overall thread length. Saw a 3MT to 3AT collet adapter somewhere online. I will check with Jeff as you suggest.

Thanks,

Jeff

http://www.loganact.com/tips/collet.htm
 
Thanks Tommie and again Jim,

Awaiting response from Hardinge to my email. Tools4cheap has what i need for the Atlas spindle to 3AT collet adapter. Life is good.

Thanks again,

Jeff
 
I have the same chuck. 1J collets... before you look them up, make sure you are sitting down. they are $$$
 
daveph345 have you tried 5c collets in your chuck.
 
I did, 5C's are longer (roughly .300)
IJ collets do not have the internal threads for collet stops that 5C's do. They do appear to have the same taper.

All the same, they seem to hold work fine. I didn't push it super hard, and those more knowledgeable than me can comment if this is a horribly bad practice.
 
Back
Top