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Lord Farquhar
06-08-05, 08:04 PM
Takefu Suminagashi
Japanese multi layered steel
I bought two meters of this steel from Dick Tools a few months back and This is my first experiences with it.

I cut a section 6-inch long or about 15cm and cut the section in half so it was 16mm wide. The billet is 5.5mm thick so I thought there was some room for drawing out. I had spoken to bushman who I believe has done some stock removal of this steel and he said the pattern was rather boring and symmetrical. With this in mind I decided to forge the blade rather than cutting one. I put my small 15cm billet in the forge and brought it up to working temperature. I flattened and drew the steel out using a 3lbs smith’s hammer and I found the steel to be very easy to work with and it seemed very soft in comparison to some of the steels I have worked with. I was very careful to keep the steel in the right alignment and did not allow it to twist at all. Scale formed very quickly on the sides of the steel in very thin laminations and it seemed to happen quicker than some of the steels I have used. The scale was very thin and came of very easily and had the appearance of paper ash as it was so thin.

I drew a tang out and formed a blade. The ending dimensions from the 16mm wide 150mm long bar are, 115mm blade 120mm tang and the blade is 20mm wide and 3mm thick.

When it came to the grinding and finishing the steel was not soft like it was under the hammer but it was much like other carbon steels. As I had forged the blade and had given it a good beating I achieved some nice wavy laminations on the sides of the bevel and I ground the sides of the blade and that sowed some nice figure and some nice pools.

I hardened the blade via bringing it up to critical temperature (non magnetic) and quenched the full blade (not the tang) in oil. I ground of and scale from the quench to leave a bright blade and then I tempered the blade to straw using the blast from my forge. I then linished the blade then polished then sharpened then etched in ferric acid for about 30 mins . The blade now is clean and pretty and very sharp.

Pictures to follow.

My opinion?

For the price this is great steel that will produce some very nice blades that are beautiful and functional.

The edge holding seems to be great as it is shaving sharp with out much effort and it sliced threw my skin and I barely noticed.

Its easy to work and soft and malleable under the hammer


On the down side the laminations are of a low or non carbon steel and it made the sides of the blade very soft and very easy to scratch. I personally do not think this is a suitable steel for wood cutting knifes but really it is a kitchen knife steel and I think it should stay there. I tried cutting a branch with it and did some feather sticks with the blade and it did the work with ease but I noticed some scratches on the sides of the blade that were not there before.

Just my thoughts J

MotorbikeMan
06-08-05, 08:31 PM
sound interesting Lord F, looking forward to seeing pics :)

Alick
07-08-05, 10:56 AM
Soft sides ! - reminds me of a cheap kiridashi marking knife I once bought, the edges were a little rough so I thought i'd tidy it up a bit. The soft laminate was so soft you could almost mark it with your fingernail, the hardened side was pretty hard I found out when it blunted my file in two strokes :(

The frosts mora laminated blades are similar - the outer layers are again very soft, but the overall blade, even long slim shapes, are tough and handle very aggressive cuts when woodcarving.

Nice review :)

Bushmanuk
10-08-05, 10:26 PM
I agree with lord farquhar this steel is really nice steel to forge, but is a little tough to stock remove,I suspect that it is supplied quite hard.
The outer layers are a little soft when oil quenched so I tried a couple in water,one at cherry red and the other much hotter(bright red) both blades held together extremely well with no distortion or cracking, the edge rockwelled at 65 and 66 respectively. The side laminations are much harder than in the oil and more resistant to scratching,(though still a little soft) there is carbon present as there is some martinsite present where I put some thick blobs of clay.I would estimate a carbon content for the laminations at about 0.3 to 0.4.
As it stands this steel makes excellent Japanese hunters and it will be an easy task to case harden the sides if a strong bushcrafter is required, (I have tried this with three layer scandi blades and it makes them very scratch resistant and a nice dark colour).
I look forward to seeing Lord farquhars blade as stock removal leaves the pattern looking a little bland and the blade I lightly forged was only a little better, a heavy hand will getthe best results.

Lord Farquhar
10-08-05, 10:40 PM
I was hopeing you see one of yours forged blades now i have to photgraph my rubbish.
I will try to get some pix of my poor atempt done.

Bushmanuk
13-08-05, 09:25 PM
Mozzy.
From what I have seen of your work, no one could call it rubbish,especially you!
You seem to have a good forge instinct so dont be hard on yourself.
I have made a blade and case hardened it Actually turned out very easy to do as you dont need worry about depth,just enough to make the sides more resistant to scratching. As a bonus it seems to enhance the apearance.
Ive put a couple of blades on the gallery and look forward to seeing your.
Paul.

Lord Farquhar
14-08-05, 12:54 AM
i saw you blades Paul .. very nice
I think forging the steel a little adds to the appreance as you can achive pool etc on the sides as well as a wavier pattern on the bevels.

How did you case harden the sides?

dtalbot
14-08-05, 09:34 PM
Want to see these as that steel has certainly taken my fancy!

Lord Farquhar
18-08-05, 10:26 AM
Pickies as promiced
http://i5.photobucket.com/albums/y185/1131972/jap2.jpg

http://i5.photobucket.com/albums/y185/1131972/jap1.jpg

I think this steel would be better with a flat grind personaly
The top picture you can see the blade sides have a textured effect..... next time I will only use the light buffer, the steel is soft of the sides and the buffer actualy cut into the steel quite a bit.

dtalbot
18-08-05, 12:42 PM
Nice,
I'll get some as soon as my group buy for Dicks.biz hits the magic €300 for free shipping, Then just need to find someone to teach me hot metal hammering!
Cheers
David