Pen Mill Sharpening

[Woodchopper]

I'll try it again in the proper forum. I think. <g>

I made this jig to sharpen my pen mill and it worked pretty good. I used a Jet wet sharpener, but any grinder with an adjustable tool rest should work. I turned a half inch piece of square keystock to .250 inch on one end. Aligned the pen mill to the flats, adjusted the tool rest to where it's square, and angle matched. Using a marker and rotating the wheel by hand gave me the angle it needed. You just have to be careful to not get into the side of the wheel with the cutter that is not being sharpened. One could probably turn down a square acrylic to do the same. A light touch is all that's needed. I hope this helps someone. You guys have helped me tremendously. Thanks.
Hope I did it right this time.

Dell

 

[GBusardo]

Hi Dell, I usually touch up my mills with a diamond hone on the up and down surface. I am curious, does your set up grind to a decent angle? Also, grinding the face like that, how do make sure all the cutting surfaces are exactly the same length? That's an interesting set up though

 

[rherrell]

Interesting. I think I'll give it a try.

 

[Woodchopper]

To answer some questions, the aluminum tool rest is adjustable. Just mark the cutter where you are going to grind with a black marker. Eyeball that angle to start with, then turn the wheel by hand just enough to rub (some of) the black off the cutter. Adjust accordingly. That should keep your angle as it was. Even if it's off a little, all four cutters will be the same angle anyway. Just don't get too carried away. If you get the angle right to start with, it will take less time and metal off. Also, be careful that the rear cutter doesn't get into the side of the grinding wheel.
Do it lightly, go slow. That's one advantage of the slow sharpener. And you can use calipers to keep the four cutters even.
Here is more pictures at different angles. A lot depends on setup, but it's not hard. I used dial (well digital <g&gt calipers to measure the cutter length, and as a square to keep the cutters sguare.

Dell

 

[randyrls]

Originally posted by Woodchopper

To answer some questions, the aluminum tool rest is adjustable. Just mark the cutter where you are going to grind with a black marker. Eyeball that angle to start with, then turn the wheel by hand just enough to rub (some of) the black off the cutter. Adjust accordingly. That should keep your angle as it was. Even if it's off a little, all four cutters will be the same angle anyway. Just don't get too carried away. If you get the angle right to start with, it will take less time and metal off. Also, be careful that the rear cutter doesn't get into the side of the grinding wheel.
Do it lightly, go slow. That's one advantage of the slow sharpener. And you can use calipers to keep the four cutters even.
Here is more pictures at different angles. A lot depends on setup, but it's not hard. I used dial (well digital <g&gt calipers to measure the cutter length, and as a square to keep the cutters sguare.

Dell

Dell; Very interesting.

To get the angle accurate, use one of those Wixley Digital Angle Gauges. Adjust table to 90 degrees, set the gauge on the table, zero it out and set desired angle. Mark the angle on the pen mill.

I have seen a setup with sandpaper glued to a flat plate. Drill a hole at a slight angle thru a piece of wood 1-1/2" thick and about 6" long. 2x4? The hole must be a good accurate fit with the mill center pin. Use a spare brass tube?? To sharpen, slide the mill along the edge of the plate and sandpaper. Take the same number of strokes on each edge.


From here you are on your own.

 

[Woodchopper]

Dell; Very interesting.

To get the angle accurate, use one of those Wixley Digital Angle Gauges. Adjust table to 90 degrees, set the gauge on the table, zero it out and set desired angle. Mark the angle on the pen mill.

I have seen a setup with sandpaper glued to a flat plate. Drill a hole at a slight angle thru a piece of wood 1-1/2" thick and about 6" long. 2x4? The hole must be a good accurate fit with the mill center pin. Use a spare brass tube?? To sharpen, slide the mill along the edge of the plate and sandpaper. Take the same number of strokes on each edge.


From here you are on your own.
[/quote]

I've been fixin' on getting one of those, just never got around to it. Maybe tomorrow.

Dell