Sharpening router bits

I was routing some tracks for a marble game experiment and was getting messy cuts and some burning. I figured, the router bit is probably getting too dull.


To sharpen carbide cutters, you need a diamond wheel. Proper diamond wheels are quite expensive. I once tried using a diamond tile saw blade. It cut the carbide, but far too rough.

I also tried a diamond stone one time, but that was slow and tedious.

A reader, Andrew Scott, had suggested using a Dremel tool with a diamond wheel to sharpen carbide saw blades. Dremel tool diamond wheels are relatively cheap. I tried it, and it seemed to work. The diamond wheel was just fine enough for sharpening.

It's really quite simple. The most useful piece of information I can give you is that it actually works!

I first sharpened just the flat part of the cutter, and it cut much better after that.

Later, I accidentally routed into a screw in my jig, so I sharpened again, this time sharpening the outside edge as well. Although for round-over bits and other bits with inside curves, a wheel really wouldn't work that well.

I have since been told that dust from sharpening carbide is hazardous to your health, so I'd recommend doing this outside on a windy day. Though I suspect, as a hobbyist, only sharpening the occasional bit, the dust exposure is still less than in it would be for someone sharpening blades professionally, even with protective equipment.

And this is the jig I was using to route out those tracks. I'm using my 3D pantograph, with a 3D template to cut some ramps for a marble toy experiment.

Before and after.

You can see some lines along the grooves in the track pieces at right. Those are from pre-routing a square channel to make less work for the ball nose bit, but I routed some of those too deep.

More sharpening articles:

Chainsaw sharpening
with an angle grinder

See also:

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