This video originally aired on January 4, 2013.

I today's video I'll do a little simple saw doctoring. It's common to find old backsaws who's spine has been knocked down too far at the toe, giving the saw blade a tapered appearance. While canted saws certainly were made for many decades up until around the end of the Civil War, they're rare to find on the old tools market today. Most backsaws that we find by makers like Atkins & Disston have rectangular saw blades, not canted blades. The easiest way to tell is to look at the angle between the toothline and the toe and heel of the saw. They should be 90 degrees in a rectangular saw blade and different from 90 (but add up to 180) in a canted saw blade. Rectangular saw blades with improperly installed spines will also often appear to have the toe angled out in front of the spine instead of perpendicular to it.

Usually, the backs on these saws have been knocked down either due to being dropped, or in a misguided attempt to repair a bend in the blade. Such is the case with the saw I'm working on today, so I'll remove and reinstall the spine properly.