Thread: Sharp end mills

I'd vote for the thin cut off wheel in an angle grinder.
With respect to the cutter with the chipped corner, it may be better to grind all four corners with a deliberate chamfer. You won't get a square corner out of the cutter but it will stop the corners being further damaged. I've seen cutters sold like that somewhere.

Michael

Originally Posted by Anorak Bob

Hey Phil,

Is cross feed involved in the sharpening operation or only "plunge" grinding? If cross movement is a feature of the sharpening process, how are you achieving it?

And is there anything that you would change about the design?

Bob.

Hi Bob,
Plunge cut is the method used. I dress the wheel first and set the stop so the end mill is just kissing the wheel. I grind the primary clearance first then raise the table to the appropriate height and grind the secondary clearance.
The only real modification was to make a detachable, larger diameter, head for the stop so I could sharpen slotting drills as well. I had to do this because of the different length cutting edges of a slotting drill. The inside end of the cutting edge has to be in line with the outside of the wheel. When the holder was rotated 180 deg, I needed to place a spacer between the holder and the stop mount to realign the inside end of the cutting edge. The original specs meant that the holder missed the stop. With the larger head on the stop it didn't interfere with anything when grinding either cutting edge. Of course with an end mill, all four cutting edges are the same length. Just going out to the shed to take some pics.

Phil

Here are some pics.
First one is the larger head and the second one is the plate that mounts to the grinder work rest.

Phil

Another couple of pics. One showing the setup and the other the adjustable work rest for the grinder.

Phil

Originally Posted by Anorak Bob

Along these lines? (see below)

I have another question. Some of my cutters are badly chipped. To remove the damaged section entirely before resharpening the end, how does either cutting the section off with a thin slitting wheel like those that fit a Dremel ( the ones that go puff when the disintegrate ), or sanding it off with a coarse disc on a faceplate sander sound? I have a pair of unused Charkson end mills that lost their corners in transit from the UK. The larger is about an 1 1/4" in diameter. The rest of the cutters have suffered from misadventure in my hands.

BT

Bob
Identical, in every detail to what I had in mind.
Even to using the Hercus Indexer, & even the colour is the same!
regards
Bruce
ps I will get to set up some photos again, just been having trouble getting them across from the Computor File. Cannot figure it out, but hoping Sue can help.