I've got some nice dedicated R8 endmill holders in typical N-Am hole sizes, 0.375, 0.500. I rarely use the 0.250" or larger ones so kind of regretting buying a set way back when without knowing better. These have the lateral set screw to retain EM's against the anti-rotation notch ground in the shank. (Is that called Weldon shank?). I need to get some smallish metric EM's & typically their shanks are nominally same diameter as cutter vs. so-called 'standardized' NAm shank.
This got me thinking. My N-Am holders were not exactly cheap. I could probably justify buying say an ER32 holder for my R8 mill & collets and be set up for pretty much any EM, imperial or metric in this range. Is there a fundamental disadvantage to using ER collet for this purpose? For example there must have been a reason for integrating the set screw in this style. So is ER collet more prone to slipping in the collet? Coincidentally I bought a 0.5" carbide EM on ebay that had no ground flat so ended up grinding one in order to use. They said CNC so presumably some of those machines use spring collets? For reference I would say probably 0.5" would be the biggest size I'd consider running in ER.
What are good ER brands runout/quality wise?
I'm guessing tool change would be about the same effort - unscrew the ER cap vs. loosen the set screw?
This got me thinking. My N-Am holders were not exactly cheap. I could probably justify buying say an ER32 holder for my R8 mill & collets and be set up for pretty much any EM, imperial or metric in this range. Is there a fundamental disadvantage to using ER collet for this purpose? For example there must have been a reason for integrating the set screw in this style. So is ER collet more prone to slipping in the collet? Coincidentally I bought a 0.5" carbide EM on ebay that had no ground flat so ended up grinding one in order to use. They said CNC so presumably some of those machines use spring collets? For reference I would say probably 0.5" would be the biggest size I'd consider running in ER.
What are good ER brands runout/quality wise?
I'm guessing tool change would be about the same effort - unscrew the ER cap vs. loosen the set screw?