There's nothing wrong with A2

[Brian Holcombe]

I’ve never quite understood why manufactured laminated blades are still commonly available in Japan but aren’t a ready made option in the US. They’re inexpensive and very good, I’m sure they would cost a very similar amount to the current crop of alloy steel blades.

Given that A2 is basically used because it is easily heat treated for mass manufacturing, it would seem an excellent solution to use pre-laminated irons.

Stanley provided laminated blades into the early 20th century, probably up until WWII. One if my friends brought a plane over for me to sharpen, it was not exceptionally old and it had a laminated iron. It sharpened beautifully.

A technology still being produced during that time period should not be difficult to reproduce now, and obviously isn’t given that Hitachi does it.

I modified my LN #7 for one of these blades and it was the best thing I did to that plane. I prefer it to the O1 iron in my #4. O1 is ok but laminated plain carbon or mild alloy is better still.

[Vincent Tai]

I’ve never quite understood why manufactured laminated blades are still commonly available in Japan but aren’t a ready made option in the US. They’re inexpensive and very good, I’m sure they would cost a very similar amount to the current crop of alloy steel blades.

Given that A2 is basically used because it is easily heat treated for mass manufacturing, it would seem an excellent solution to use pre-laminated irons.

Stanley provided laminated blades into the early 20th century, probably up until WWII. One if my friends brought a plane over for me to sharpen, it was not exceptionally old and it had a laminated iron. It sharpened beautifully.

A technology still being produced during that time period should not be difficult to reproduce now, and obviously isn’t given that Hitachi does it.

I modified my LN #7 for one of these blades and it was the best thing I did to that plane. I prefer it to the O1 iron in my #4. O1 is ok but laminated plain carbon or mild alloy is better still.

Brian, this is very interesting and something that is in line with my interests. I remember a short discussion on Insta where Oliver Sparks the plane maker mentioned to someone that a British company tried to recreate the laminated plane irons but then had huge issues with wrapping and even more warping during grinding. I remember chuckling a little because the solution is simple enough in Kanna irons made by blacksmiths, use the ura design and as for the bending along the length of the tool; the black smith pre-bends the other way. The same thing is done with knives etc. I remember thinking there is no way that factory is going to have a smith pre-bending and straightening irons by eye. My chuckle faded as those Tsunesaburo irons popped into my mind. I have never heard complaints about warpage in those, and they look very machine finished. How Stanley and Tsunesaburo manufacture these thin irons at a mass manufacturing level befuddles me. The thin part is really what befuddles me, when you get the steel down to that slim slim Stanley style, the mild body isn't very resistant to the warping during hardening.

I had predicted this when I was making vintage tapered irons just a short while ago; these were very small, 1-1/4" width. Because of their width they were quite slim in thickness too. Only one iron was satisfactory for HT (trying to forge in minus 21 Celsius not including windchill creates some problems). I adjusted for some extra warpage but the iron curved and bellied out so much that I was shocked. It ignored the pre bends going the other way, and the amount of belly the other way I had put in; a little more than in a kanna iron was completely for naught. The carbon face was so bellied out I could've been holding a laminated scoop of sorts. I'm rather good at coaxing things to flat so I did, and it is easy enough by hand eye, clamp, tempering and a hammer with copper shims to adjust these irons. (though in the end I did put a crack in it when I bent it one way too far and then back the other while the iron was cold). I would be amazed if any factory did that with those Stanley style irons. My theory I've just thought of is they can get the irons laminated very very neatly, so that the high carbon layer is the same thickness throughout all the irons. One single die set that presses the irons to a predetermined curve and belly and then off to the HT, where because of the uniformly thick high carbon layers, the irons all warp back to relatively flat. A session at the surface grinder, being careful to mind the tension in the iron and maintaining that tension without grinding too much or too little on either face gives that final surface, or a lapping machine as the final step.

There is no escaping warping in these irons, it is the nature of the HC vs the mild. So we prebend the tool. This is why a Kuro ura kanna is prized, grinding and adjusting the kanna is usually needed after the HT.

I suspect the knowledge to make these in factory has died out a little in the western world. One would have to make and sell a lot (like a lotttttt) of irons to sell them at a price near solid irons. Solid irons are literally just Water jet, CNC some holes and slots, and HT, and surface grind/ lap. Throwing laminated tools in there, a whole new crop of steps and challenges. Brian; did Stan ever tell you what happened with his plans for laminated western irons? Perhaps he could be enlightening. Though I do remember him saying there would be a slight ura etc, which leads me to think that these were smaller scale blacksmith made items.

IMG_4321.jpg IMG_4329.jpg
The little iron I was working on. Photos are upside down, but at this point I've given up trying to flip every photo in preparation for this site. Apologies for the clay still on the iron, I'm lazy.

Also I've realized this has nothing to do with A2. oops.

[Brian Holcombe]

Nice work, Vincent!

I recall that from a long while ago that Stan had mentioned plans for it, and I know of a blacksmith making them individually for western planes with an ura (I don't recall who, offhand). The Tsunesaburo one that I have was flat on the back but I tapped out to create an ura.

Having the ura is definitely better but I think they either pre-bend them or bent them in a machine to set them after heat treating. Or perhaps they have some sort of hydraulic clamp for them while they're being quenched (I have no idea, just speculating).

I'd imagine it becomes very predictable when the steel and iron are of uniform size and the heat treatment process is always the same and so they can immediately counter it through some process. They sell retail at about $45, so the landed cost in the US is probably about $15-$20, so the price to a manufacture buying these in the hundreds at a time should be cheaper still but maybe it is still yet more expensive than making them in A2. They're probably $4-$5 in materials plus processing for A2 irons, so I'd further assume it is nearly a wash.

[Vincent Tai]

Nice work, Vincent!

I recall that from a long while ago that Stan had mentioned plans for it, and I know of a blacksmith making them individually for western planes with an ura (I don't recall who, offhand). The Tsunesaburo one that I have was flat on the back but I tapped out to create an ura.

Having the ura is definitely better but I think they either pre-bend them or bent them in a machine to set them after heat treating. Or perhaps they have some sort of hydraulic clamp for them while they're being quenched (I have no idea, just speculating).

I'd imagine it becomes very predictable when the steel and iron are of uniform size and the heat treatment process is always the same and so they can immediately counter it through some process. They sell retail at about $45, so the landed cost in the US is probably about $15-$20, so the price to a manufacture buying these in the hundreds at a time should be cheaper still but maybe it is still yet more expensive than making them in A2. They're probably $4-$5 in materials plus processing for A2 irons, so I'd further assume it is nearly a wash.

Thanks Brian!
There are good Damascus manufacturers, along with san mai type construction. A single layer weld should be pretty cheap for those guys. Perhaps the west does have avenues in terms of getting the laminations done at a big scale. I don't think a clamp would be used while quenching, cracking would seem like the end result. A bit of both prebend and bending after the HT seems plausible. I hope I can get the ones from Stu at some point soon, just to see their construction. And then it's off to recreate some with a proper ura.

[Warren Mickley]

Also I've realized this has nothing to do with A2. oops.

Your post about manufacturing problems may have an awful lot to do with A2. I don't think we know to what extent manufacturing considerations played a role in choosing A2 for today's small manufacturers. A2 machines easily and apparently behaves well in heat treatment. Tools steels that did not have these qualities may have been eliminated from consideration. Traditional edge tools were forged, not machined, so that opens up possibilities for different types of steel.

About a month ago I was thinking about blacksmiths cranking out chisels in the 18th century. A journeyman cabinetmaker could buy about 8 chisels from dealer Christopher Gabriel for just one day's wages. And Gabriel became rich off the deal. A guy who made chisels all day for years could have made tens of thousands. That is enough volume for a blacksmith to learn to compensate for heat treatment problems and be awfully good at it. That is one of the benefits of repetitive work, that one can foresee problems and take appropriate steps to avoid them.

[Vincent Tai]

Your post about manufacturing problems may have an awful lot to do with A2. I don't think we know to what extent manufacturing considerations played a role in choosing A2 for today's small manufacturers. A2 machines easily and apparently behaves well in heat treatment. Tools steels that did not have these qualities may have been eliminated from consideration. Traditional edge tools were forged, not machined, so that opens up possibilities for different types of steel.

About a month ago I was thinking about blacksmiths cranking out chisels in the 18th century. A journeyman cabinetmaker could buy about 8 chisels from dealer Christopher Gabriel for just one day's wages. And Gabriel became rich off the deal. A guy who made chisels all day for years could have made tens of thousands. That is enough volume for a blacksmith to learn to compensate for heat treatment problems and be awfully good at it. That is one of the benefits of repetitive work, that one can foresee problems and take appropriate steps to avoid them.

Warren, I suspect the availability of precision ground A2 and it's very appealing behaviour in HT is quite appealing. There are knife makers who order small rectangular precision ground blanks by the hundreds; perfectly sized for CNC to do their thing. A2 is very available. It retains its tolerances after HT even better than O1. Receiving your steel precision ground is awesome for small manufacturers. Minimal movement in the steel after HT is even better. Personally the few A2 tools I have perform fine. I don't own any A2 chisels though. A2 is quite well received in the knife world.

A blacksmith that made tens of thousands of chisels could probably adjust and compensate for movement by eye and feel only for much of his career. Repetitive work is something I am benefiting from trying to make planes and the irons that go with them. It'll take a few more tries but I do look forward to the first tapered iron that goes in the quench all curved and bent one way and comes out straight and flat. The same goes for chisels. I suppose I could bypass all this by ordering tapered A2 blanks or getting O1 round bar machined into chisels but there is no fun getting rid of the advantages of a laminated tool. Also a mill and shaper are expensive .