MetalworkingFun Forum

I good project if you have a 5C collet chuck for your lathe. By member Bogstandard (John).

http://www.modelenginemaker.com/index.ph...w.html#new

Enjoy!

Ed

A lot of 5C collets (certainly the better ones such as Hardinge) have fine internal threads in the collets themselves to accomodate collet stops. Hardinge still sells the stops or (of course) you can make them yourself.

The style shown by Bogstandard is considered to be a "dead length" stop. Because the stop doesn't retract with the collet as it tightens you get very repeatable lengths, usually within "a tenth or two". However, the downside is that if you have a polished finish on the part you are chucking, a dead length stop can cause the collet to marr the finish. This is rarely a problem, and often easily fixed is it does happen.

(10-01-2012, 07:05 PM)PixMan Wrote: [ -> ]A lot of 5C collets (certainly the better ones such as Hardinge) have fine internal threads in the collets themselves to accomodate collet stops. Hardinge still sells the stops or (of course) you can make them yourself.

The style shown by Bogstandard is considered to be a "dead length" stop. Because the stop doesn't retract with the collet as it tightens you get very repeatable lengths, usually within "a tenth or two". However, the downside is that if you have a polished finish on the part you are chucking, a dead length stop can cause the collet to marr the finish. This is rarely a problem, and often easily fixed is it does happen.

Ken;

Please correct me if I am wrong here but that stop is held in the spindle taper is it not? If so it turns with the spindle and should leave no mark on the work piece.

"Billy G"

With the "dead length" stop the part can't move as the collet draws in, the collets slide down the part and can mark it.

(10-04-2012, 04:19 PM)f350ca Wrote: [ -> ]With the "dead length" stop the part can't move as the collet draws in, the collets slide down the part and can mark it.

Ah, now I understand what Ken was saying. More accuracy but at the risk of marring the part.

Thanks!

Ed

Yup, me too. I just never heard it that way before. Sorry Ken.

"Billy G"