End Mill Sharpening Fixture

[rossbotics]

I designed and built this tool for resharpening end mills on the surface grinder, I must have over 100 dull ones I'm sure, Anything under 3/8" in diameter I pitch when there dull, From 3/8" and above I use to send off and get reground, Anyone who does allot of milling will tell you that it's not very hard to wrap up a few hundred bucks worth of cutters in a heartbeat, So I decided to build a unit that would attach to the magnetic chuck on my surface grinder and make it more versatile.

The unit has a 5/8" thick 1018 steel base with a 2° angle machined left and right of the center line on one side of the base for grinding the fishtail on the end of the cutter and for sharpening the sides without interference from the other side of the cup wheel during side grinding.

All parts were made from 1018 steel, 1020 D.O.M. Tubing, O-1 Tool Steel and 6061 Alum. all 1018 steel parts were oil blackened except the base, The spindle was made from a piece 1020 D.O.M. tubing, It was machined to a very tight tolerance with a high polish finish, There is .0002" T.I.R on the spindles diameter from one end to the other, The spindle housing was bored in a 4 jaw chuck with a honed finish which is .0005" over the spindles diameter, They slide together like glass, There is a floating pull knob on the rear of the spindle which has 2 ball bearings, It has a spindle locking pin on the front of the housing for tightening the collets and a indexing collar on the rear for indexing up to 6 flutes, It can grind the primary and secondary clearance angles on the front or sides.

Allot of thought and work went into the making of this tool, And many hours to complete.


Below are some photos of the tool from assembly to the grinder.
As always thanks for looking and happy machining

Doug
Attachment 9520

Above- note the 2° angle on the side of the base plate

Attachment 9521

Above- note the slot in side of the vertical aluminum plate, that's for adjusting the spindle up and down for the primary or secondary grind.

Attachment 9522

Above- note the indexing and locking pins in the spindle housing.

Attachment 9523

Above- note the indexing collar

Attachment 9524

Above- end view of fixture showing stylus

Attachment 9525

Above- side view of tool

Attachment 9526

Above- other side

Attachment 9527

Above- on the grinder

Attachment 9528

Above- on the grinder

Attachment 9529

Close up on the grinder