Solid end mill holders vs collet holders

solid holder vs collets

First of all, TG collets are no where near as good as the ER type. 2nd, I know what all of the liturature says, but I have run my own tests and had different results. I never run endmills in er collets unless they are 1/4" or less in shank diameter. It is easy enough to get solid holders for 5/16" and up. If I wanted to use a collet to run a larger endmill, I would use a milling chuck, not and er or tg. There is simply not enough contact to hold an endmill with standard drill collets. The milling chucks are straight on the outside of the collet and well as the id. Not to mention the length of the collet in a milling chuck vs. and er or tg. With all of that said, I still get better results from solid holders. I run all types of stainless steels, titanium, aluminum and other mild steels, and all of them seem to cut better in solid holders. I push my feeds and speeds. I run 30 hp okumas, a typical speed in feed for a 3/4 e.m. in aluminum for me would be 11500 rpm, 300 ipm, .6 depth of cut, channel cut or pocketing. I run 2" miltecs about the same except .25 depth of cut. when I run carbide insert cutters in steels, I can clearly see a longer tool life with solid holders vs milling chucks, and again, I run 500-750 surface foot and .005-.010 chip load, 1/4" depth of cut in 17-4, 15-5 stainless. I would have guessed the milling chucks would work better in steels with insert cutters because of the concentricity, but it is not true, or at least in my type of cutting.
charlie