We’ve all encountered the problem of looking at our router bits and thinking that they’re a bit worse for wear. So here’s the question : do we salvage old router bits or do we just trash them? First thing to do is to take a good hard look at the router bit. Is it salvageable? By that I mean that if you notice chips and bits that are supposed to be there but aren’t then of course the answer to that is to trash it and get a new one. Next thing to do is to find out if it is actually dull - ie is it just dirty and that’s why you’re not getting the finish you require when using it? WD40 is the solution to that - carefully clean the pitch and resin off the router bit and take another look at it. After cleaning it, you need to test it’s sharpness. How do you test the sharpness of the router bit? Some have suggested using your fingernail to test the cutting edge of the bit ie if you manage to take off a bit of the surface of it, it’s probably sharp enough. Ever wonder why woodworker’s fingers and nails are the way they are…well this would explain it to a certain degree :-) If you discover that the router bit is in need of a sharpen, then you’ll need to get yourself a diamond paddle honing stone. There are different grits available (they aren’t going to break the bank - pretty cheap so get yourself at least 2) - ranging from 180 - 1200 grit. Generally the lower the grit number the rougher it is (similar to sandpaper) - so you basically work yourself up the grit numbers. Most woodworkers have a middle of the range diamond honer eg 600 grit paddle is sufficient for most minor touch up sharpens. If you’re diligent in keeping your tools in top nick then that’s probably all you’ll need. Otherwise, if you’re one of the more forgetful woodworkers and leave the touch up jobs till the bit’s in dire need of a sharpen, then you might want to go with something like a 325 grit paddle first and then follow it up with a finishing hone with the 600 grit. In most instances all you need to do is about 5 passes of the carbide cutter on the paddle and that’ll do the job.

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