|Project by Oldtool||posted 05-30-2015 11:32 PM||1087 views||0 times favorited||5 comments|
My interest in striking knives was generated by Adam Cherubini’s article in the April 05 issue of Popular Woodworking, number 147. I’m sure most of you will recognize the drawing of two types of knives as seen in photo #2. My thought was to modify the sketch to allow the knife to be used on both sides of dovetail layouts.
My modification was to use two shallow angled sides, rather than making one skewed cutting edge with only one point. I achieved this by making the two sides at an approximate 86 degree angle from the cutting edge. After completion and testing, I’ve determined that this will work as I hoped, or at least I’m satisfied with the results. I’ve used a spear pointed commercially made striking knife and found it to either wander from the desired cut by following grain, or in a few occasions shave the edge off of my aluminum 4’ yard stick. This knife seems to eliminate both of these situations, by keeping the cutting edge low to the wood.
Photo #3 shows the tool steel bar stock from which I cut the knife, purchased from MSC Direct, O1 tool steel, 1/8” bar stock.
Photo #4 shows the knife after all cutting, filing, sharpening, and polishing.
Photo #5 was directly after hardening, using a Bernzomatic torch, with MAPP Gas & Oxygen, purchased from the big box store, as well as photo #6.
Photo #1 is the finished knife, polished & sharpened again, to the point where it shave hair from my arm.
I primarily used this project as a learning experience for myself, because I intend to restore many of my old wooden planes, and I’ve never heat treated steel before. As such my takeaways from this are:
Completely forming the pointed end & sharpening the blade prior heat treating worked out well, without any warping of the thin knife edge or the pointer end, as I’ve read could occur per some sources for heat treating.
Heating the steel with this torch occurred very quickly to a bright red, and no home made kiln was required.
Thanks for viewing.
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