Repairing old end mills

[Brento]

So i have a carbide endnill or two from my last job that is chipped at the corners can i just take diamond files and turn them into chamfers and the will cut fine? What if its only one corner that is chipped. If i just file that corner will it be ok or should i do all of the corners

 

[EmilioG]

I have a Carbide Guhring 6 flute end mill that has 3 small chips from running it too slow and it works just fine.
I found out that you have to spin these carbide EM's faster than HSS. Anyway, the EM still works great. If the chips are small and you have other corners, it should still work OK. I never re-hab EM's. I just toss 'em or keep them for grinding into something else one day.

 

[Brento]

I chipped mine the same way or from to much of a bite bc i was new at it. Im just starting out for a hobby and want to use them as much as possible since i dint have the cash to replace. I cant grind them since i dont have a grinder and if i remember it wasnt the greatest finish. I think i saved it to do crappy work that was only going to get boogered up already. I csn see if i can get them sharpened from someone that does them at work but it could be expensive.

 

[benmychree]

If one does have a grinder with a diamond wheel, one can grind the ends back to sharpness and also grind the secondary relief; regrinding to center is a bit more trouble, but if you don't need to penetrate the work like a drill, it does not much matter, don't worry about grinding off the coating, it will still be on the face of the flute and still does some good. a re sharpened mill might not cut like a new one, but is good to rough with at least.

 

[Cobra]

If it's a decent sized end mill, you can very reasonable have it ground here: http://endmill-sharpening.com/
Great service and prices.
Jim