End mill chatter?

[mikey]

Use a magnifier and look at the tips of the cutter. See the little hook at the tip? If any of them are not fully formed and sharp, the end mill will not cut well.

 

[Hukshawn]

Bugger..... 3 perfect flutes and 1 chipped one... And I know exactly when it happened. Just before that last pass I y traveled a tincy bit too far and bumped the vise jaw. I hear it clunk... Jebas!

 

[Hukshawn]

Got the DTI set up to see if I can see any wiggle while the table travels... Bigger issue, x table is .0035" higher on one side of travel than the other. That's not even a tram issue, that's just the table being out to lunch...
I dunno anymore. Lol
I guess I sorta got what I paid for when I bought a mini mill.

 

[mikey]

Bugger..... 3 perfect flutes and 1 chipped one... And I know exactly when it happened. Just before that last pass I y traveled a tincy bit too far and bumped the vise jaw. I hear it clunk... Jebas!

Yup, it only takes one.

 

[higgite]

Got the DTI set up to see if I can see any wiggle while the table travels... Bigger issue, x table is .0035" higher on one side of travel than the other. That's not even a tram issue, that's just the table being out to lunch...
I dunno anymore. Lol
I guess I sorta got what I paid for when I bought a mini mill.

Could the X gib need snugging up?

Tom

 

[Hukshawn]

Yes. Both ends of the table get quite snug...

 

[woodchucker]

Might just get a stick of stressproof or 12L14 and make life easier. Personally , and its just my opinion, but unless I had at least 2 or 3 hp I would not fool with roughers, they are made to work, requiring a pretty good feed, and the rough surface teeth and a flexible mill set up do not lead to a happy situation. A nice fresh 4 flute endmill will likely suit you better.

I use roughers all the time, and I think my 8520 only has 3/4 hp. I value them as they take a good amount off, and I find they don't give me a problem usually. I did destroy one a few weeks ago, on what must have been a chunk of forged metal. (DAMN)

 

[Buffalo20]

I use roughers all the time, and I think my 8520 only has 3/4 hp. I value them as they take a good amount off, and I find they don't give me a problem usually. I did destroy one a few weeks ago, on what must have been a chunk of forged metal. (DAMN)

I also use them with less than 1 hp, with no issues.

 

[john.oliver35]

Yup, it only takes one.

So I have wondered this but never tried it - If one were to grind away the damaged tip so that only the other three touched the material would the cut improve?

 

[mikey]

So I have wondered this but never tried it - If one were to grind away the damaged tip so that only the other three touched the material would the cut improve?

I haven't done this, John. Once a tip goes, the cutting action is disrupted and the end mill can actually dig in and ruin the work as it did here, or break and launch itself. I simply retire the end mill when a tip is worn excessively or is damaged.