Here is a little device I have put together which enables me to resharpend my stellite tipped blade. In doing this I have saved money and also extended the service life of my rather expensive blade ($300-$350).
Cost of the jig would be $90 - $100 for the dremel plus a pair of high quality drawer slides, threaded bar and nuts, scrap aluminium and some wood. Of course this jig is quite suitable for sharpening bimetal, carbon steel and heat treated tips <1 TPI - 3TPI blades. I haven't tried finer blades yet.
Picture 1 shows the diamond disc sharpening the back of the tip. Notice the indexing plate. This enables a uniform sharpening for all the tips unless the blade has some run out.

Here is a close of the plate just before it slides to it indexing point.

Now the plate is in position.

In this image you can see the two springs. When pushing the sharpener towards the blade the spring on the travelling jig relaxes and the spring at the other end of the jig pulls the indexing plate into position. As the sharpener passes over the blade tip, both springs relax leaving the plate stationary. When the sharpener passes back past the tip the spring on the travelling arm pulls the plate back to enable the blade to be pushed down to set the tip for sharpening.
You will also notice that there is a threaded rod that is not only the pivot point for the plate, but also a means of adjusting the height of the plate to allow for different indexing distances between tips, as well as allowing the machine to sharpen the face of each tip.

In the following images you can see that the jig has been readjusted to sharpen the face of the blade tip.


If you have any design ideas regarding this let me know.
regards
Tim