Thread: Grinding v. Milling: how to cut a blade

I'm new to straight razors.

I've played around with metals and heat for a while. My grandfather was a tool and die man in Detroit (purely practical), and my father got a PhD in Metallurgy (purely theoretical). I'm interested in making my own razor.

(Which, by the way, is hilarious, because I can't yet properly hone a razor. But if I can get the angles right and the spine exactly parallel with the cutting edge, I can have a honemeister hone it for me.)

It seems that most grinds (anything more hollow than a wedge) is ground on a wheel that spins perpendicular to the blade. So a turning, grinding wheel hollows out the blade. (Is that wheel usually of a width that exceeds the width of the blank, or is an expert had needed?)

Wouldn't it make more sense to clamp a piece of, perhaps, 1/8" O1 fully annealed steel and mill away the same material? On a regular vertical mill, the blank would need to be vertical, and the mill head would be whatever shape would produce a nice concave hollow. The blank would then be turned around 180 degrees and the other side would be hollowed out.

Is this a worthwhile pursuit? Have any blades been made like this?

Thanks in advance,

Matt

Matt,

What you're describing is essentially what the forging process does. Finish grinding is done after hardening which would make milling difficult at that point as the blade is probably harder than HS steel. Perhaps carbide tooling could be used but the impact of the mill might shatter the blade.

Yes, it can be done. But likely the cost of production dictated grinding as a method and tradition. Some of the abrasive stones used in history were six feet in diameter or larger. And dangerous. Freehanding the blade would be faster than milling it out, but I wouldn't bet against a CNC setup for speed either.

You could mill your razor, heat treat it, then use an abrasive roll or grinding stone of appropriate diameter chucked up to do the finish grinding in step down to final grit fashion. Watch so you don't ruin the heat treatment, but hey, what's cutting fluid for eh?

It is possible; you could use a wheel narrower than the blade and move the milling head up and down while the work piece is clamped vertically.
But as mentioned, even for a 5/8th size blade you need a wheel with a diameter too large for the average milling machine. Of course with CNC you could get away with a smaller wheel.

Just an idea… but a lathe could handle a bigger wheel… chuck a wheel between the centers, clamp the blade in the tool holder and move the slide to hollow out one side. Then rotate the tool holder 180deg and the other side is hollowed out (not all tool holders can rotate 180deg to get to the other side so you may have to move the work piece).

Of course the practice of grinding on a lathe is found upon, (and the setup is lass than safe because of the open wheel) but is possible if precautions are taken… not standing in the direct line of the wheel, spinning the wheel at low speed, a cloth to cover the ways and a thorough cleanup of the machine when done… oh! and you will need lots of shims.