On 2011-04-09, Karl Townsend wrote:
On Fri, 8 Apr 2011 20:13:13 -0700, "PrecisionmachinisT"
wrote:


"Ignoramus30421" wrote in message
om...
Thanks to Pete C's advice, I am milling aluminum with HSS end mills.
These are Interstate end mills that Enco sells for $2.99 a piece.

I have to say that they work nicely, at 12 IPM, 2000 RPM, 2 flute,
1/4" diameter of end mill.

I am making those aluminum turner's cubes, which is a process that I
automated, so it takes me no time. All my friends want them.

Right now I am using depth of cut that is 1/3 of the end mill
diameter, and I am wondering if perhaps I am short changing
myself. Can I use depth of cut that is 1/2 of diameter? 1 diameter?
This process involves both slotting, as well as side milling.


http://www.archive.org/download/tuco...nsultant20.zip


Nice calculator. I hadn't seen this before. The speed feed DOC are way
off the chart compared to what I do. I see it says up to .375 on a .25
EM. I'd be unlikely to try it on a full slot where you're cutting both
sides. But for $3, why not? No guts no glory. They may be assuming
high pressure flood coolant to keep the chips cleared. Something you
don't have.

I see the speed feed are both about 1/3 of what you are running. About
right on a small non production mill, IMHO.


Back to DOC. I've thought the ease of breaking an endmill must vary
with the square of diameter. Or put simply, a 1/16 breaks if you look
at it cross eyed, I only go maybe 10 thou or a fraction of a diameter.
AND only use it when nothing else will do. A 1/4 still breaks easily,
I'd be cautious at one diameter. Go up to 1/2 and you can cut real
deep - 2 diameters wouldn't cause fear.

I've not seen the above in calculators. So, its just one guy's
experience. It may be related to chip removal on my hobby quality
equipment.

Keep in mind, I'm not like Pete. I've broke a lot of end mills.

Karl

Yes, I will use at 1/2 diameter.

i