Learn to think up-side-down and backwards

Today I was making a replacement handle for a hewing axe.  I was using a piece of hickory that a friend of mine felled several years ago.  I was working my way around a small knot near the end of the haft with a card scraper and was not very happy with the result.  Though it’s very tough, hickory (especially air dried stock) can “tear out” pretty easily, and I was experiencing that phenomenon “in spades”.  I concluded that I would get a better result if I used a higher cutting angle.  But I had to think for a moment about how to accomplish my goal.

Unlike a scraping plane that doesn’t require a “hook” to be drawn on the cutting edge, a card scraper is totally reliant on that feature.  The hook is generally drawn with a burnisher at between 75 and 90 degrees to the main surface of the scraper.  So here’s where it gets a little screwy.

Keeping the main surface of the scraper close to vertical yields a LOW cutting angle:

the hook at a low cutting angle

the hook at a low cutting angle

When the included angle between the workpiece and the main surface of the scraper is decreased, the cutting angle is actually increased and the shaving is actually more “closely broken” .  This process yields a very fine shaving with very close “accordion pleats” caused by the immediate “curling” created by the higher cutting geometry.

009

The hook at a high cutting angle

The next time you’re scraping stringy or highly figured stock, trying raising your cutting angle by “lowering” your scraper.  It’s Zen, be one with the scraper.  Think upside down and backwards, you’ll be glad you did.

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