Gloster 5c collet chucks

[dazza]

Does anyone use the above?theres a massive price difference compared to the likes of bison chucks so im wondering about their quality/accuracy.

[Jonathan]

The main difference with a collet chuck is that the run-out is generally much lower than for a normal 3-jaw chuck. That doesn't necessarily make your parts more accurate though - if you can machine the part in one set-up, without removing it from the chuck between operations, then the end result is the same. If 1-10mins setting up the part concentrically in a 4-jaw chuck is not a problem, you might as well do that as it's a lot cheaper.

Collet chucks also grip over a larger area, so can potentially hold with a higher stiffness and are less likely to make marks on the part.

[dazza]

ta,my other reasons for looking at collet holders are pneumatic release and bar grabbing.