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View Full Version : What carbide are you running on AL ?



nheng
11-08-2005, 09:11 PM
If you use carbide inserts on aluminum, what type of inserts, cut and chipbreaker (light, medium, roughing, etc.) are you running?

Especially for small-ish diameter, precision work, I've heard that Korloy is about the only game in town with its sharp (relatively) edge and steep rake. Any other out there worth trying?

I use DCMT and TCMT inserts mostly. Den

dbuck
11-08-2005, 09:49 PM
Sandvik

TCGX 11 02 04-AL H10 = 2(1.5)2
or
TCGX 11 02 08-AL H10 = 2(1.5)1

They fit my TCMT 11_02_nn holders.
They are not cheap.
You will love them on AL.
You can also shave .001 cuts off steel with them.
About 20 degree back rake on these razors.

Evan
11-09-2005, 12:31 AM
Other than aluminum castings why use carbide on AL? I use HSS. The only insert I use on AL is a Valenite diamond insert in a boring bar for inside threading. Why? Because it is the right shape. http://bbs.homeshopmachinist.net//biggrin.gif

speedy
11-09-2005, 01:29 AM
HSS here as well. It`s cheap and sharpening your own keeps the skills up and the knowledge alive.

ken

DR
11-09-2005, 05:43 AM
"Especially for small-ish diameter, precision work, I've heard that Korloy is about the only game in town with its sharp (relatively) edge and steep rake. Any other out there worth trying?"

I use the Rouse-Arno inserts. Available from HB Rouse, (815) 943-4426.

Never bought the Korloy, I've seen them on sale with very good prices, so I may spring for a box next time I'm buying.

These razor sharp, high positive inserts will make believers out of guys who say you can't get carbide as sharp as HSS. We use them for aluminum, brass, plastics, light finishing in stainless, even turning skinny pieces of mild steel where the part can't withstand the deflection forces of less positive rake carbide tools.

With the chip breaker of the insert, if your machine has high enough rpm, aluminum like 6061-T6 (nasty material for turning) can be run without getting the dangerous bird nest of stringy chips.

nheng
11-09-2005, 07:48 PM
Carbide with the right chipbreaker is one of the main reasons I like carbide, even for aluminum.

Evan, One thing I can say for the HSS, I was finish turning a 0.125" x 1.25" turned down end of a shaft last night and reached for my father-in-laws old HSS bits. Where the carbide (ones on hand at least) caused excess deflection and resulting chatter, the HSS, with its sharp rake, produced a very fine finish and only very slight taper due to deflection.

Carbide isn't meant to be sharp, but to develop cutting edge temperatures and "plow"-like action. But I can't wait to get a box of the "sharp" ones http://bbs.homeshopmachinist.net//smile.gif

Den

Evan
11-10-2005, 12:32 AM
If you want really sharp for turning aluminum the best is plain old hardened and drawn high carbon steel. It takes an edge better than anything else around and it won't overheat on AL. I have some that came with my Unimat and use them from time to time. It is amazing how sharp they are.