What life to expect from end mills?

I have a 2mm radius 1-4" shank tapered ball mill I’ve been using a fair amount, and I had a problem today with it seeming to grab the material while cutting. It’s been used mostly on MDF and some poplar. I just finished going over every single screw and adjustment on the machine, and it seemed to be in good shape. I wonder if the bit is getting dull - examining it under a magnifying glass doesn’t seem to show much.

What kind of life should I expect from an end mill, and is there a way to tell if one is getting dull before it breaks or ruins a carving? Listening isn’t an option, since I use a shop vac with the dust boot.

Thanks in advance!

@falviani IMHO for any edge tool, it all comes down to the finish it leaves. Router bits, turning gouges, saw blades, etc; they are all the same. When you are no longer getting the finish off the bit that you used to get or that is acceptable to you, it’s time to either sharpen it, or replace it. I don’t think that there is any magical formula that we can use to determine how many miles we will get on edge tools before the edge is gone. Certainly, MDF beats up our mills. It seems to cut easily and to be fairly soft in the grand scheme of things, but the binder is very abrasive. Feed and speeds strongly influence how long our bits will last,too.

All that said, I don’t know if I’ve helped you at all, Frank. :grinning:

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