Finally compared HSS versus carbide end mills on a real job

I ran the same part in 6061 aluminum last week with a cheap HSS end mill first, then swapped to a carbide one. The HSS took me 6 passes and the finish was rough, had to deburr everything by hand. Carbide did it in 2 passes with a nice surface finish, no extra cleanup. The carbide cutter cost $18 more but saved me about 45 minutes of setup and sanding time. For a 20 part run it paid for itself easy. Has anyone else switched and found carbide worth the extra cash for small batch work?

3 comments

3 Comments

gracej9917h ago

Keep using carbide for aluminum unless you're doing one-off prototypes where tool cost matters more than time. The time savings add up quick even on small runs, especially when you factor in not having to deburr every edge. Honestly once you get used to the finish from carbide it's hard to go back to HSS.

david_walker9713h ago

@gracej99 nailed it about the time savings. I switched to carbide for aluminum a while back and the finish is night and day. Even on a 5 part run the extra cost is nothing compared to hand deburring for an hour. I run feeds a bit higher with carbide too, just make sure you've got good chip evacuation or it'll weld up quick.

anna7174h ago

Oh man, I gotta admit I was totally on the other side of this for a long time. I always figured carbide was overkill for aluminum since it machines so easy with HSS. But after reading what @gracej99 and you said, I grabbed a few carbide end mills to try on a recent batch of parts. Yeah, the finish is way better, I can't argue with that. And I didn't have to sit there with a file for 20 minutes cleaning up edges. It really changes your perspective when you actually run them and see the time saved. Still, I'd say it depends on the job, maybe if you're just making a one-off bracket for yourself, HSS is fine. But for anything you're getting paid for, carbide makes sense.