Bought a cheap 2-flute end mill set on Amazon, figured they'd be trash but they've held up through 80 aluminum parts so far

I usually stick to name brand tooling from MSC but needed some 1/4 inch end mills quick for a rush job last month. Picked up a 10 pack of no-name Chinese ones for like $35 (you know, the ones with the blue coating). Figured i'd be swapping them out every 20 parts but i'm still on the first one. Cuts arent as clean as my carbide stuff but for roughing passes they work fine. Anyone else had luck with the cheap stuff or am i just getting lucky?

2 comments

2 Comments

milesrobinson1mo ago

Honest truth is the blue coating probably chips off and gets embedded in your coolant lines.

harris.uma1mo ago

Miles, the blue coating is actually a phosphate layer that's soft and designed to wear in, not chip off in chunks. When it breaks down, it mostly turns into microscopic particles that just circulate as normal wear debris and get caught by the filter. I've seen people run these coated rings for 100k miles without the coolant turning into a glittery mess. You'd have to really abuse the system or not change the coolant for ages to get any real clogging from it. Have you actually had that happen with one of these or just heard the rumor?