10-01-2012, 07:05 PM
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.
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.