M40 CUSTOM BLADE – Concept to Reality

M40 CUSTOM BLADE – Concept to Reality

This original design was created by a friend who was looking for a small camp knife/ferro rod combo. I had him cut out his idea in cardboard so that he could hold it in hand and better feel the size/shape and ergonomics. This usually creates a better final product.

M40 CUSTOM BLADE – Concept to Reality

After a few minor revisions, he emailed me his idea on notebook paper background so I could get the exact size of the final product.

M40 CUSTOM BLADE – Concept to Reality

I could then make a cutout and trace it onto the steel. I used a 3/16” thick billet of 1095 high carbon steel for this blade.

M40 CUSTOM BLADE – Concept to Reality

Here are some pictures of the rough 2D cutout shape, and the first coarse grind of the bevels.

M40 CUSTOM BLADE – Concept to Reality

After finer grinding of bevels, detail cutting/grinding of the outer shape, and drilling for handle slabs and lanyard hole.

M40 CUSTOM BLADE – Concept to Reality

And into the forge she goes for a trip up to about 1600 degrees (glowing red-orange). This is the transition temperature for hardening high carbon steels. Once we get a good glow, it’s time to quench the blade…

M40 CUSTOM BLADE – Concept to Reality

A quick plunge into a bucket of used motor oil locks the hardness into the cutting edge. This is called a “differential quench” as it hardens the cutting edge, but preserves the toughness of the spine.

M40 CUSTOM BLADE – Concept to Reality

Here it is all cleaned up, fine ground and ready for tempering. Tempering means it goes into the oven for an hour long stay at almost 500F. This relaxes tension in the steel, toughens the blade, and brings the hardness down to a manageable 60Rc.

M40 CUSTOM BLADE – Concept to Reality

After tempering and final buffing/polishing, it’s ready for some handles!

M40 CUSTOM BLADE – Concept to Reality

I have a nice burled piece of Hawaiian Curly Koa wood that should look nice…

M40 CUSTOM BLADE – Concept to Reality

Handles made, shaped, finely sanded and polished to a nice sheen. These were attached with peened brass tube stock. The Koa wood makes some beautiful patterns that iridesce in the light.

M40 CUSTOM BLADE – Concept to Reality

Now it’s time for a matching ferro rod and sheath…

M40 CUSTOM BLADE – Concept to Reality

M40 CUSTOM BLADE – Concept to Reality