Endmill Relief Grinding


(martin redeby) #1

So since very long singe flute endmills are not the most sturdy I bought some shorter ones and thought that either I don’t need to? (since its plastic I’m cutting) or I’d try to do my own relief grinding…

So anyone done any relief grinding of their end mills? there are obviously specialty tools for this sort of thing, that I don’t want to invest in. :slight_smile:

Any good diy solutions?

My initial thought is to mount the bit in the benchtop milling machine we have at work and try to mount a appropriately sized diamond wetstone on the xy table and maneuver it in place very gently…


#2

Relieving is a specialty. These days, the grinding is done on a CNC tool grinder (essentially a 5 axis mill with a grinding wheel pack). In the old days, it was done using a relieving attachment on a lathe, or appropriate setup and fixture on a tool grinder. (the relieving attachment is similar to a tracing attachment, but has a cam timed
to the spindle)

See https://www.youtube.com/watch?v=GATVn8rLLBk for example


(Richard Cournoyer) #3

I do it quite often…Remember it doesn’t need to be pretty to work. (2mm End Mill, see photo)

How: $10 HF grinder, $12 Diamond wheel (eBay) and a steady hand with a cordless drill"


(martin redeby) #4

Well then, I have a couple of days (until my bits arrive) to figure out how I’m going to mount my dremel on the xy table of the benchtop mill… Because I’m so not doing this by hand.

Is there a desired amount of relief? one chipload?