crazy san mai ?

butcher_block

butcher_block

Joined
Dec 6, 2004
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how can i tell what steel will move faster under the hamer
like i heard that 15n20 moves real slow compared to 1084 (hence 1084 thinning faster in the bar)
im looking at a hi carbon core with SS sides (i have some cpm154 laying around)
both steels im looking at are about 18% extra alloy one othe option im looking at fro a core is about 13%
im looking to find this out because i have 1/8 thick core and 3/32 sides but i dont want the core to show after grinding more then a 1/2 inch up the grind
does this make any sence at all :o
want to do this for some kitchen knives
 
If you're just wanting to lay up 3 layers san mai style and you're not doing any real drawing of the steel after the weld, I don't think that the "ratio of squish" should matter much. The trick for this one will be finding the right sized rectangular tube to put it all into since you need zero oxygen involved to weld stainless.

Would it be possible to tool wrap it and just set the weld inside the "envelope"?

I'd look forward to spending 4 or 5 knives worth of steel at least to figure out the welding...

-d
 
If you have acess to a TIG machine, Tig weld all the seams first then forge weld. I do this with my regular damascus but have not tried it with SS. If you can not do it this way you can make up a tube to fit and purge it before you weld up the end.

Chuck
 
butcher_block said:
how can i tell what steel will move faster under the hamer
like i heard that 15n20 moves real slow compared to 1084 (hence 1084 thinning faster in the bar)
Click to expand...


I'm not sure my comment will be terribly useful here, but it is my experience that nickel (and I would assume steel with a pretty strong nickel content like 15-n-20) tends to 'take over' a damascus pattern. For instance, you can use .005-inch pure-nickel sheet with .060 1084 and it will look like the layers are pretty close to equal sometimes and I doubt the 1084 is squishing out because the nickel is forging more slowly.
I would be surprised if 15-n-20 was actually forging that much differently than 1084. --- Now if we were talking about 52100 ....
 
ok well i guess i ll have to jsut try it and see how much the SS thins out or if i can even get the SS to weld to the core
 
yep, 1084 and 15N20 move about the same. The silver metal in damascus will dominate the pattern, this is why it looks best to use 2 to 3 times black steel(like 1084) over nickel steel.

For your san mai project, you want the center piece of steel to be about half the thickness of the outer layers, this is if you want it to show little at the edge. Also forge the edge bevels pretty thin before you start grinding. Forge welding SS is no fun, you have been warned :D
 
To figure the amount of reveal of the San Mai core to the blade take the % of core to the total thickness of the billet. I mig weld the perimeter of the billet and dry weld it together.

When etched the Nickel bearing steel does not etch as fast and you burn off the plain Carbon steel at a higher rate. This will give the impression that the bright layers are really thicker than they are as part of the mix.

If you are going for a stainless clad choose a 400 series over a 300 series steel, it is more compatable in heat treat. I made 52100 clad with 300 series and when you harden the 52100 the 300 series is softened. When you anneal this mix it hardens the 300 series and softens the 52100....Take care...Ed
 
Give Ariel an email he is quite the magician with the SS san mai blades.He makes it look too easy :cool:
 
Since we're talking about stainless sides on a carbon core, one way to get the same effect with A LOT less trouble is to use 15-N-20 on the sides instead of 300 or 400 series or other 'blade stainless'.

15-N-20 is very, very stain resistant. In fact in my not-so-scientific analysis (anecdotal experience), it's at least as 'stainless' as ATS-34 and 154. I've had scraps of these materials mingled together on the floor exposed to HT salt residues, moisture and general weather. The 15-n-20 pieces (which could be identified because they were all cut in uniform squares while the other scraps were irregular) stayed bright while the others rusted and pitted. It is true that the stainless characteristics of some SS alloys improve when properly heat treated, but good luck getting that condition and properly hardening the 1084 core at the same time.

15-N-20 handles pretty much like 1084 and the two will HT well together.
 
well heres the thing since i can heat treat cpm154 ,3v or 10v at about the same range i was goingto put 10v in the core with cpm154 sides heat treat of ast temp of 2100 and a temper of 1000 should give about Rc 62-63 while the clad im not sure about

also i know cpm154 will not like that tempering temp (sensitization) but so be it it will still be better at not rusting then the 10v
 
JCaswell said:
Since we're talking about stainless sides on a carbon core, one way to get the same effect with A LOT less trouble is to use 15-N-20 on the sides instead of 300 or 400 series or other 'blade stainless'.

15-N-20 is very, very stain resistant. In fact in my not-so-scientific analysis (anecdotal experience), it's at least as 'stainless' as ATS-34 and 154. I've had scraps of these materials mingled together on the floor exposed to HT salt residues, moisture and general weather. The 15-n-20 pieces (which could be identified because they were all cut in uniform squares while the other scraps were irregular) stayed bright while the others rusted and pitted. It is true that the stainless characteristics of some SS alloys improve when properly heat treated, but good luck getting that condition and properly hardening the 1084 core at the same time.

15-N-20 handles pretty much like 1084 and the two will HT well together.
Click to expand...

That's good news! I wish I had known before I ordered stuff from Kelly Cupples, I'd have had him throw in some larger pieces of 15n20 and some thinner 1095 to do some san-mai kitchen knives.

Next order I suppose :)

-d
 
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