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Rant: I thought those cheap tool steel end mills from that online auction were a total scam.
A guy at a shop in Tacoma swore by them, so I bought a set of five for $30 to try on some aluminum. The first one chipped on the second part, and I was ready to write them off. But after dropping the speed by 200 rpm and doubling the feed, they actually ran fine for a whole batch. Has anyone else found a weird setting that makes a bad tool work okay?
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karenh561mo ago
I had a set of those no-name end mills from the same auction site, the ones that came in a plain cardboard box with no branding... The first one I tried on some 6061 aluminum made a horrible squeal and the cutting edge just folded over after like three passes. I was ready to throw the whole lot in the trash. But then I remembered an old machinist I used to work with who always said you gotta "scream through aluminum" so I cranked the speed way up to like 4500 rpm and hit it with a heavy flood of coolant. That little cheap end mill just started chewing through the material like butter after that, no chipping at all. It's weird how sometimes a tool acts like it's junk until you find that one perfect combo of speed and feed that wakes it up. I've got a couple more in that set that I haven't even tried yet because I'm almost scared to mess with a good thing.
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aaron3053mo ago
My buddy had a similar thing with some off-brand drill bits. He was ready to toss them after they kept walking on steel. Then he tried a way heavier peck cycle, like a quarter inch at a time instead of his usual light touch. They drilled straight through a whole plate after that, no problem.
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andrewreed3mo ago
A quarter inch peck? That's insane, he must have been hammering on that drill press.
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