Really cheap eBay/Chinese endmill

[Bob Engelhardt]

I'm new to endmilling on my horizontal mill and I've already broken one endmill. Expecting to break more, I got the cheapest HSS I could find for my learning process (1/2"):


Wow.

[wierdscience]

Oddly enough, the Chinese carbide endmills are pretty good. Their HSS stuff on the other hand is abject garbage.

[RB211]

I find "Chinese + HSS" to be a very bad combination, even for learning.
Chinese carbide is much better but I've been buying USA carbide from small businesses that have popped up selling generic USA made.
With HSS, I stick to name brands.

[DennisCA]

I do like having HSS tooling available, I found some cheap NOS roughing end mills that have been very handy. Though I use them with coolant.

I've ruined more than one carbide end mill by accident, whereas an HSS one would've been fine. I think the best compromise is to get an indexable end mill, for sizes over 12mm anyway.

[mattthemuppet]

not sure I see what the issue is? There are grind marks still, is that it? Otherwise it looks like a standard non-center cutting endmill. I bought some Chinese 6mm HSS roughing endmills and they worked pretty well, as well as some 6mm 3 and 4 flute which were passable at best. If I want to see if HSS will cut something, those are what I use

[A.K. Boomer]

Wow --- maybe its a new design to cut with serrations lol

[Bob Engelhardt]

not sure I see what the issue is? There are grind marks still, is that it? ...

Look closely at the cutting edges. Only one of them is straight/continuous.

[Bob Engelhardt]

I was looking at it to see if I could regrind it and I noticed that the primary facet has no relief! That's not normal is it? What would be a normal relief angle?

[reggie_obe]

What material are you cutting? Slot, pocket, surfacing, perimeter? Speed and feed? Endmill on a horizontal, why?

[I make chips]

Being a cheapass I usually get the wuhanium hss end mills. If you run them very slow like 100-200 rpm they'll do ok for a while.
The curry based ones on the other hand seem as they're made from 12L14.

[mattthemuppet]

I have a whole bunch of endmills that look like that, including from big name manufacturers. It just depends on how the flutes are ground. In fact, on smaller end mills it's a useful indicator of when the tips start getting dull as that little hook disappears.

eg. OSG

[J Tiers]

This^^^^^^^^

the shape is normal. Being super brittle may not be.

Buy cheap, get cheap. If it could cost that to get a good product, it already WOULD cost that.

[old mart]

You can't really tell from a photo whether an endmill is any good. Perhaps you should try taking smaller cuts.

[Bob Engelhardt]

What material are you cutting? Slot, pocket, surfacing, perimeter? Speed and feed? Endmill on a horizontal, why?

Mild steel & aluminum. Very little so far. On horizontal mill & with 4" cutters (my maximum), I can't cut stock held in a spindexer because the spindexer won't fit under the arbor. I'm sure that I'll find other good uses ... such as your "slot & pocket".

[Bob Engelhardt]

I have a whole bunch of endmills that look like that, including from big name manufacturers. It just depends on how the flutes are ground. In fact, on smaller end mills it's a useful indicator of when the tips start getting dull as that little hook disappears.

eg. OSG

Oh! Well, I just learned something, thanks.