On Tue, 01 Mar 2005 17:29:30 -0600, jackK
wrote:

Grant Erwin wrote:
wrote:

This is a dumb question, but what are the relative advantages of
4-Flute vs. 2-Flute end mills, and on what applications should one type
be chosen over the other?

Harry C.


2-flute for slots, 4 flute for when you want higher feed rates (keeping
the advance/tooth constant, the only way you can up your feed is by
adding teeth).

I don't buy the steel/aluminum answer, sorry.

GWE
That's ok Grant, alot of people will understand what i was talking about.
yes you can cut alum with a 4-flute and you can cut steel with a 2-flute.
alum. roughing I like 3-flute cutters and 2-flute for finishing.
(4-flute tend to wad up the alum to easily)
2-flutes on steel are not my favorite due to slower sfm which results in
slower feed rates. I'd use 4 or more flutes on steel.
I generally use two flutes on aluminum because the cutter can be run
faster with a heavier chip load without clogging. Steel gets 4 flutes
because the usual limiting factor is rpm, not depth of cut. And
because they neeed to be run slower four flutes gets to be run at
twice the feed of two flutes. Even with the cutter buried in steel as
far as it can the speed is usually slow enough to allow chips to get
out of the endmill with four flutes. But hey, that's just me. YMMV
Eric R Snow,
E T Precision Machine