Sometimes, actually often, you don't know what you don't know. Many years ago I purchased an ER40 collet set to fit my milling machine in NMTB40. I was thrilled that the set would hold everything from 3mm-26mm. And since the collets were collapsible by 1mm, I was golden, even if all my cutters were Std shanks. Through all this time, holding some cutters, I had to really screw the collet nut in quite a bit for it to grab. I didn't think anything of it. Then I read this:
By MariTool
It is always the best to use the max size shank tool for the max size collet. For example if you need to hold a .625 endmill it is aways best to use a collet that has a range of .625-.586 which is called a 5/8 collet. You can easily use a 16mm collet which has a .6299-.591 capacity for a 5/8 shank tool. I do it all the time with no problem. I guess you just have to keep in mind the more you compress a collet the less clamping you will have. I would say a 10-15% reduction. Concentricity should be the same.
So I looked around, and sure enough, inch sized collets. So I ordered a few. Son of a gun!! The cutters fit snugly in the collets. Well, time to order more inch collets.
By MariTool
It is always the best to use the max size shank tool for the max size collet. For example if you need to hold a .625 endmill it is aways best to use a collet that has a range of .625-.586 which is called a 5/8 collet. You can easily use a 16mm collet which has a .6299-.591 capacity for a 5/8 shank tool. I do it all the time with no problem. I guess you just have to keep in mind the more you compress a collet the less clamping you will have. I would say a 10-15% reduction. Concentricity should be the same.
So I looked around, and sure enough, inch sized collets. So I ordered a few. Son of a gun!! The cutters fit snugly in the collets. Well, time to order more inch collets.
