Well, I now do a LOT of work with 1/8" solid carbide end mills. Yes,
clearly, I don't have the spindle speed, either, but they are so much
stiffer than the HSS cutters. Also, because the solid carbide ones have
1/8" shanks, they are actually CHEAPER than many HSS with 3/8" shanks.
I've had great results in aluminum with the carbide.
How many have you broken? Iggy is just learning CNC *and* general
machining speeds and feeds, in my opinion, he doesn't need to be using
carbide tooling that he will have a much greater chance of breaking at
this point. He should also not be doing much with end mills under 1/4"
dia or so for a while until he gets the hang of things.
No, but you will have a much lower risk of breaking one if you use HSS
instead of carbide, and you will get comparable milling results with
either type, so there is no benefit to using carbide and the is a
drawback to using it.
Surprisingly few! They are amazingly tough, too! I had an accident
once where I
forgot to set the Z, and a 1/8" carbide end mill plowed full depth and
a 1/8" aluminum panel at 60 IPM. It was cutting like it was meant to do
that until I hit
estop, and it broke then.
I cut a lot of 1/8" and thinner instrument panels with small holes for
pots and switches
and connector cutouts, and the 1/8" is just about perfect for that.
Generally, I cut everything
with the same cutter except for small holes for 4-40 screws and the
like. So, the 1/8"
end mill is becoming the general purpose tool here. At $3 - $5 each, I
don't cry a whole
lot when I break one, I buy 10 or a dozen at a time.
Pete, I always had bad luck with HSS. But, perhaps, it was because I
did something wrong or they were dull. Anyway, I am willing to give it
another try under ideal conditions. So, would you recommend one
particular HSS drill bit (say 3/8), I will buy that one and will give it an
honest try, at the exat recommended speeds and feeds.
I run carbide on the Clausing 5914 and the Millrite MVI, and it works just fine.
These machines are big enough to handle carbide. I also use HSS, and that too
works just fine. But carbide is far more brittle than HSS, and so is more
vulnerable to accident or misuse.
Chinese carbide and HSS are not as good as western carbide and HSS, but I have
been using Taiwan-made carbide-tipped boring bars with great success.
The Chinese HSS end mills in the blue plastic tubes with paper labels
with the size
rubber stamped on them are abominable crap! I used to buy HSS end mills
some surplus flyers, and got Hanita, Iscar, etc. brands. Then, they
started sending that
Chinese CRAP and I stopped buying from those outlets. Some of them were
CLEARLY sharpened freehand!
Now, if I buy end mills larger than 1/8", I get M-42 HSS, with Cobalt.
These have much
better wear properties than plain HSS. I have to admit I am spoiled, I
learned on a big
box of surplus Pratt & Whitney Stellite cutters, which are the best of
both worlds. Tougher
that HSS, but wear hardness nearly as good as carbide. The M-42 is
nearly as good, and
a FAR cry above plain HSS, which I tend to wear out darn quick, even on
There is a world of difference in carbide. Shop eBay for brand name
stuff. For regular end mills Hanita is my favorite. Many other made in
For really removing metal FAST, get Sandvik R390 replaceable inserts.
Makes steel cut like AL. It calls for no coolant - all the heat goes
in the chip. STAND back cause you get a shower of dark blue chips.
I've got a 1 1/2 inch unit I run at 2000 RPM 15IPM and .200 DOC and
these really are too conservative a numbers.
"The Kid" says every shop in the country must have people stealing
cutters and selling on eBay. The deals on top end stuff is
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