Switched from HSS to carbide endmills on aluminum and wow what a difference

Been running a Haas VF-2 for about 5 years now and always used HSS endmills for aluminum parts because they were cheap and I thought they did the job fine. Last month my tool rep talked me into trying a 3-flute carbide endmill for a batch of 500 parts I had to run. I was skeptical because carbide costs about 3 times more per tool. First pass I noticed the surface finish was way better with no burrs forming on the edges. Pushed the feed rate from 40 IPM to 80 IPM and the chip load looked perfect. Ended up cutting my cycle time from 4 minutes per part down to 2 minutes and 15 seconds. The carbide tool lasted through all 500 parts without any wear while I would have swapped HSS tools at least 3 times. For anyone running aluminum parts in production you really gotta try carbide even if the upfront cost hurts. Has anyone else noticed better tool life with coatings like TiB2 on aluminum?

3 comments

3 Comments

olivia_bailey23d ago

Are you serious about the 2000 part run? @simonl11 that's insane tool life for aluminum, how bad was the price difference?

simonl1123d ago

Buddy of mine over at a shop near Detroit had the same kind of experience. He was running HSS on some 6061 plates and breaking tools left and right. Swapped to a ZrN coated carbide endmill last fall and said his finish looked like a mirror finish with no cleanup afterwards. He told me he cut his tool change time in half across a 2000 part run. You ever mess with variable helix carbide to cut down on chatter?

hill.andrew23d ago

Funny you mention variable helix, because I actually think about that same kind of idea when I'm trying to open a stuck jar lid. You know how you twist it one way and nothing happens, but then you kind of wiggle it at a different angle and it pops right off? That's basically what variable helix does for chatter, it breaks up the harmonic frequencies that make the tool vibrate. Your buddy probably noticed it on those 6061 plates too, since aluminum loves to stick and hum when you push it hard. Kind of wild how the same physical principles show up in a machine shop and in your kitchen.