Simple Carbide Grinding

[cbcnc]

Hi Guys,

First let me say that I can appreciate the skill and investment in the setup needed to do first class tool grinding. I will send my carbide sawblades and bits to the sharpener rather than do it myself.
What I would like to do is be able to touch up some of my carbide tools like my masonry bits or there has been a time that I wanted to turn a straight router bit into a round nosed cutter.
Is there a grinding wheel that I can put on my bench grinder that will sharpen carbide? What grit will give me a good finish? Are there any inexpensive fixtures that I could use?
Thanks for your input.

Chris

[Scrit]

The tooling people use CBN wheels - steel wheels with diamond attached in what I believe is a sintered coating. Not cheap! We have a couple (made by Norton) for doing profile grinding

[HuFlungDung]

Use natural diamond to grind carbide and CBN for high-speed steel.

A diamond wheel may seem expensive, but if you reserve it only for carbide tools, and don't abuse the thing, but let it cut at its own rate, it will last a long long time. Compare this to sharpening carbides on a green silicon carbide wheel: yucky! Green wheels require frequent dressing to keep them flat, and they have more of a tendency to chip the edge of the nice tool you are trying to form. Maybe use a green stone with those brazed on inserts where you've got to grind steel and carbide together at the same time. Grind a little extra front clearance using the green wheel, and then finish the carbide edge on the diamond wheel, giving a little less clearance so you can keep the steel body of the toolbit away from the diamond.

[Durkee]

Just one note to add...Resin bond wheels are great wheels for carbide and steel. Just remember that they are not meant for 'off hand' grinding. The wheels need to be smooth and true. Hand grinding tends to make these wheels out of round and erratic pressure and bouncing on the wheel with a tool could be disastrous. Resin wheels, whether they be diamond or borazon are meant to be used in fixtured grinding only.

[tigpro]

i use wheels from u.s. stadard diamond for saw sharpening 6" x 1/8" x1/4" they cost 68.00 and all the diamond are on the side of the wheel, i have cut some nice profiles with the 400 grit wheel.