Tony Immorlica replies: Yes, it is possible to sharpen a bandsaw blade, but I’ll leave it up to the reader to decide if it is really worth doing. Here’s how I do it when I’m in a pinch and can’t wait for a new blade.
First, unplug the bandsaw and inspect the blade gullets. Get a round file that approximates the curvature of the gullets, increase the tension and lower the guides so the blade does not flex too much, and go at it with the file, taking 3 or 4 strokes per gullet, holding the file horizontal. Advance the blade and continue until all the gullets have been worked. It helps to mark the starting gullet with a felt tip marker.
If the condition is really bad, you may have to first ˝joint˝ the teeth to get them all to the same level; do this by moving the blade backwards by hand while holding an oil stone lightly on the teeth. Also, after sharpening, if the cut drifts while making a rip cut, you may need to set the teeth with a saw set. For a 105˝ blade with 4 tpi, that’s over 400 teeth. It does goes fast, but not as fast as replacing that dull blade with a spare.
A couple of other notes. Instead of a file, you can use a Dremel tool with a properly sized chainsaw sharpening stone. Just briefly touch each tooth. And finally, if your blade has hardened or if carbide teeth, send it out to a sharpening service. But check the price first. It may cost less to just buy a new blade.