Re: Resolution and surface finish

--- In CAD_CAM_EDM_DRO@egroups.com, Joe Vicars <jvicars@c...> wrote:

> Material 6061-T6
> 1.5" flute length (sticking out of holder)
> Pocket Depth: .625"
> 1/2" endmill 2 flute, HSS, 2500rpm, 12ipm feed
> Climb cut, no coolant.

This end mill will flex, may have to slow down the rpm for roughing,
try 250 SFM without coolant. Take a finish cut(or two, depending on
your mill) after roughing out the pocket. Think in terms of .001-.002
depth of cut to hold close tolerances, .005-.010 for a nice
appearance. 4 flute is stiffer than two and has twice as many
cutting edges to spread out feed per tooth and hence can be fed at
twice the feed rate to get "about" the same surface
roughness/smoothness. Often in aluminum a conventional cutting
direction will result in a better finish as climb milling pulls the
chip back & it gets crimped between the tool & the work, making a
nasty finish. Use a little coolant(like tap magic for aluminum) for
dramatic improvement in appearance in aluminum.

Best,

Fred Smith
IMService