Sharpening shop questions and answers: saw blade pitting, axe eyes, and more!


Vern Burke, SwiftWater Edge Tool Works

Skowhegan, ME

Yup, it’s that time, time to answer some of the various questions I see come in to the blog and the service website via Google and other search engines. You wanted to know, I want to show!

1. (various questions about saw blade pitting)

Clean most rusty saw blades and you’ll find that the rust is only surface rust, leaving a still smooth steel surface underneath. When rust is allowed to get out of hand and too severe, it actually eats pits into the steel. Pitting can cause a wide range of problems, everything from just being ugly to causing drag on the sides of the kerf to causing a complete structural failure of the saw blade.

As a rule, pitted small circular saw blades are an immediate throw and replace. Pitted large circular blades such as cordwood saws are up to the judgement of the saw smith, except if the teeth are actually eroded. Spots of mild pitting in an otherwise nice vintage handsaw blade are ok, all over pitting that obliterates the etch and any trace of smooth steel is a throw and replace.

2. (various questions about axe eye sizes)

Usually, picking the correct handle to fit an axe eye is just a matter of weighing the head, since replacement handle manufacturer’s spec their handles by the head weight of the axe. There are exceptions to this, such as the huge 6 pound poll axe head I have in the workshop that takes the same handle as the 3-4 pound poll axes.

The important dimension is the length of the eye (fore and aft). A properly sized handle should start off as long or slightly long than the eye so it can be cut down to fit precisely. Sometimes a handle that is slightly too short for the eye can be cross wedged with a steel wedge to take up the space, but this is an invitation to split the handle.

3. (question about M tooth crosscut saw blades)

In general, I’d avoid M tooth pattern saws for working crosscut saws (although they do make a good competition racing saw). If you’re going to be sawing your firewood with it, stick with the classic Champion or lance tooth patterns.

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