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I Forge Iron

Some razors in suminagashi steel


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The blades are all made from suminagashi steel. That is a core of Japanese white paper steel (1.3% C) and sides of mild steel with contrast layers. To be honest, I don't lilke it for several reasons, but customers like it, and the man with the gold makes the rules.

Because only the core is high carbon and the rest mild, it needs to be forged carefully because it has a tendency to fold. and then you still have to make sure that the core layer stays dead center, or during hollow grinding you will find out that a portion of the edge consists of mild steel. It needs to be forged very hot to avoid delamination.

after forging, you have to grind the entire thing to final size (except the edge which is thicker) because those contrast layers only show up when they are hardened properly. The difficulty is that like the core steel, they are shallow hardened, and if you need to grind away material after HT, you lose the crisp contrast lines. Because they are oil quenched, the hardening of those lines is shallow. Water quenching would harden the razor more deeply. But it has the problem that it is so violent that the sides literally peel away from the core steel like a banana peel.

The edge needs to be left thick enough before quenching, because otherwise it doesn't retain the heat before quenching, and it will also warp. Otoh, it should be thin enough that the entire edge is hardened through, and that you can finish the hollows without getting to unhardened steel.

Post HT grinding is another challenge, because you want to grind only the edge section. The rest should already be close to size or you lose the contrast lines. this is not that easy, because the sides are soft, and the core steel is very hard. On the grinding wheel it is difficult to keep steady because the sanding belt wants to skate over the hardened section, and dig into the sides. Whether you succeeded or not is only revealed after final grinding, by which time it is too late to do-over the HT in case etching shows soft spots or places without contrast lines.

All in all, I like it not. But the shaving edge is excellent, and customers like it so who am I to argue.

8/8 razor in shokwood scales. shokwood is urethane impregnated burl with acrylic. it's a seamless whole. looks wonderful, but nasty stuff to work because it creates incredibly fine dust.


7/8 talon design with old denim kirinite scales



6/8predator design in patriot kirinite scales. You can see the etching revealing imperfect heat treatment. At this stage it was too late to do anything about it, so I finished it with scrapped scales from another project, and rounded the edge. It is now my youngest daughter's razor so that she can shave together with me (she's 7 and likes to pretend shave herself when I do)


another 6/8 design with patriot kirinite. the HT on the tang was imperfect but the HT near the edge was good and someone liked it enough to buy it


7/8 predator design in red devil kirinite



6/8razor in pepper jade kirinite


Edited by SnailForge
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I lust after your razors but Deb won't let me shave or I'd start saving up. Your posts are such lessons in practical razor making, I always look forward to your next.

About the dust grinding the handle material. Have you tried wet grinding to control dust? If you use a water soluble oil it won't rust the steel. You might need to build a cabinet to control the spray but it's old technology, lapidarists (Gem and semi precious stone cutting and polishing) have been wet cutting, grinding and polishing for centuries.

Frosty The Lucky.

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Within a cabinet it would work. It would be a hassle though. For the moment, I am thinking of buying a 2nd bandsaw. A quality one for in the basement, and then the old one can go in the shed for the dirty work where the dust doesn't bother anyone and just blows away.

For my belt grinders I am going to make a dust collector that is mounted underneath the attachments, with a forced air intake. That should cut down on the fine dust in the shop. Add an in-shop water based particle filter, and it should be ok. I am also thinking about moving my buffer outdoors. I don't use it that much, and the dust hangs in the air for a long time. I've had a couple of eye infections in the recent past, and the dust in my workshop has probably played a big role in that.

All other measures aside, one of my next purchases is a pari of prescription satefy goggles that resemble swimming goggles, in that they keep the ambient air away from the eye.

My workshop is in the basement, so very limited natural air circulation,

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Please do the step by step.  While I am nowhere near the point of being able to make even regular blades yet, I would greatly love to see it. Your blades are beautiful, and to see such artistry in process would be appreciated. 

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Basements are tough to ventilate!  I had to spray the ceiling and ductwork in one.  Very little window openings and far from the work area!  I did have an unused stovepipe outlet to a brick chimney.  I bought an inline vent fan and installed it there. It worked pretty good!  Apparently there is quite a market for such fans to supply the indoor grass farming operations!  Just an idea for you!  I still have the slightly used fan if you are interested?  Pretty high volume output. 

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Two things I have found usefull for dust removal in portible situations is ofcorse the "shop vacc" and a HVAC filter bugie corded to a box fan. The small fitinngs for vaccuming kebords and such are usful with bandsaws, wile the box fan isnt as good, with a bit of cardboard it is adaptible to a wide range of uses including a spray cabinent for paint cans and air brushes (overspray not VOC's) tho in my shop I have a windo behind one bench that i open for paint.

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