Lathe spindle ER Collet adapter build

[metalman133]

Hi Randyc,
I have just posted a question about holding an er40 chuck in a lathe chuck but I am using a 3 jaw chuck. I do have a 4 jaw independent chuck though. Do you think using the er40 in a 3 jaw is a sensible idea, provided I don't remove the er40 from it until work is complete? Or should I use the 4 jaw like you have done?

 

[darkzero]

Do you think using the er40 in a 3 jaw is a sensible idea, provided I don't remove the er40 from it until work is complete? Or should I use the 4 jaw like you have done?

Of course you may but the point of using a collet system is for the low runout. Any runout in your 3-jaw chuck will be added to the ER chuck. It's best to use the 4-jaw to dial in the ER chuck but if runout is not the main concern in your case then it would work fine.

 

[kd4gij]

I agree with Darkzero. But if you have 2 pice jaws on your 3 jaw, You gould make soft jaw and bore them for the collet chuck then it would run true.

 

[Renderbrandt]

I just finished drawing up an ER32 collet chuck for my mini-lathe.

Which one do you have?