Saturday, October 6, 2012

Sherline Lathe - Dremel grinder attachment

Working with leather as much as I do I learned to sharpen things... everything!
When given the chance I love to sharpen circular stuff on the lathe; my leather hole punch is just one of the many things that works especially well when very sharp.

I had been simply holding the Dremel up to the work piece and getting acceptable results when I decided that I could make a holder mounted onto the Sherline compound slide.

Here is the set up for putting a nice point on a punch.

The Dremel has a 3/4 - 12 thread on the end so it became a simple way to attach. Because the the grinding operation is so light to the touch the plastic housing on the Dremel is sturdy enough.

The design allows a great deal of freedom in set-up.
The Dremel is about 2" in dia and the CL of the lathe spindle is .940" above the cross slide so you need a little downward angle to hit the work piece. I also wanted the ability to angle the rear of the Dremel up in order to create a hollow grind effect if necessary.

I also like to take those small grinding stone wheels and true them up before using them with my diamond dressing bit thereby getting more than just the use of the high spot due to the out of round nature of all mini grinding stones.

See my wheel dressing invention post here

My most recent project required a very precision shape. I needed to create the mushroom half of the tool set that sets an eyelet into leather. I chucked a 1/16th ball end mill into the Dremel. With both Dremel and Sherline at full speed I was able to tune the finished part to create a perfect mushroom end.

03.03.13 Update:
Today I made V2. The original design ended up on the compound slide milling device all the time so when I rediscovered the Sherline mill vice angle holder (which I have never used) I new I could leave the Dremel attached permanently.
I like this arrangement better than the above example, it keeps all of the components closer together.

Also see Dremel Drill Chuck Attachment and Dremel Grinder, Dressing Attachment posts for surface grinding usage.

04.19.13 Update:
After discovering the Sherline motor reversing instructions I went right out to get the recommended switch at Radio-shack. The installation went smoothly; I followed the wiring diagram and it works perfectly.

I put the switch where I felt it was best situated; to the rear of the housing protected by the two bumps on the electronics housing. I oriented the switch so that when pushed to the right the motor turns in the conventional direction, pushed to the left the motor turns in reverse.

The reason for the reverse with respect to the Dremel grinder is two fold;
  1. With the grinder bit on the operator side of the tool being sharpened the sparks and the grinder dust are sent down, not up.
  2. The grinder bit and the tool being sharpened are turning in opposite directions.