How To First time San Mai/Damascus

Diego_B

Diego_B

Joined
Aug 17, 2020
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260
Hello everybody I was wondering if anyone could give me some pointers or tips about doing a San Mai or Damascus blade. I say San Mai/ Damascus in the title because part of this post was my question to you guys in what I should attempt first. I know both are complex in their own ways but I was assuming that San Mai is a somewhat easier route to take first? If so my main question here is what size stock should I start with if I want to forge a 1/8 thick knife from it? I have heard that some start their billet as close as they can get to their finalized thickness but I’m not sure. I hear that the challenge is keeping your core centered in the forging process and I was wondering if a thicker core would be better than a thinner core but this doesn’t seem to be the case? Also what do you guys use for your outer shell on San Mai? I hear about some using mild steel like A36 and 1018 but I have also heard that some use a higher contrast steel like 15n20. Basically I just want the basics on what I need to get started on a San Mai billet, forge welding has seemed to have gotten more comfortable to me so I’m not so much worried about that I’m just not sure where to start. Pattern welded steels and San Mai billets are new to me and I have never done one but I feel that I am ready to get into them and start trying.
 
Here is what I tell people asking your question:
1) Learn to forge weld flawlessly. Start with three 3X1.5X1/4" bars of 1084 (or similar) steel and practice forge welding until you can weld up three bars and draw them out into a knife blade with no de-laminations.

2) Then do san-mai. Change the outer bars to a different metal from the core. Try 15N20 for the outer layers. Practice this stack until you can make the billet, draw it out, and forge it into a blade without any de-lams ... while keeping the core centered.

3) Make a 1084/15N20 seven layer damascus billet. Add two more bars of 15N20 and two more bars of 1084, and forge a bigger billet. After drawing it out to around 10" long, cut into three pieces, clean up, stack, and forge weld again. Do this for a total of four re-stackings. You will now have a 567 layer damascus billet to draw out and make several knives from.

4) Practice making ladder, twist, and raindrop pattern damascus billets.
 
Stacy E. Apelt - Bladesmith said:
Here is what I tell people asking your question:
1) Learn to forge weld flawlessly. Start with three 3X1.5X1/4" bars of 1084 (or similar) steel and practice forge welding until you can weld up three bars and draw them out into a knife blade with no de-laminations.

2) Then do san-mai. Change the outer bars to a different metal from the core. Try 15N20 for the outer layers. Practice this stack until you can make the billet, draw it out, and forge it into a blade without any de-lams ... while keeping the core centered.

3) Make a 1084/15N20 seven layer damascus billet. Add two more bars of 15N20 and two more bars of 1084, and forge a bigger billet. After drawing it out to around 10" long, cut into three pieces, clean up, stack, and forge weld again. Do this for a total of four re-stackings. You will now have a 567 layer damascus billet to draw out and make several knives from.

4) Practice making ladder, twist, and raindrop pattern damascus billets.
Click to expand...
Thank you Stacy for your input, it’s invaluable to me. I will take all these thing into practice beginning with forge welding the 1084. Not to jump the gun here but on the San Mai what size stock is typically used?
 
You can use pieces about 6" long with a core of 1/8" to as much as 1/4" and sides of 1/16" to 1/8" and then draw the billet, or do it as a full length billet with .100 core and .060" sides. Getting a full length billet flawlessly welded up with no de-lams is a skill that takes some experience.
 
Stacy has given good inupt.
I would need to know what equipment you're dealing with before trying to add anything. If you have access to power tools, you can up the layer count significantly with no change in effort.
 
Yes, after you learn to weld up damascus, you can stack 20 layers if your press/hammer will handle that size. Now, when learning it is best to start with 7 layers. This gives the best chance of no bad welds. Cutting the drawn out billet in three pieces is the same reason. Only two welds each time you stack. Once you get it down pat, you can cut the drawn out billet into five or six pieces and re-weld. It is all a matter of equipment and experience.

One reason I use the number of pieces I did is they can be done by hand. Larger stacks and bigger billets require a press or hammer to do them well.


In a demo at Bill Moran's Hammer-in, using a 3# hammer, Jim Batson and I did a seven layer billet from start to 448 layers in five single folds - about 45 minutes total time. The billet was never allowed to cool beyond red once the folding started, and the only surface cleaning tool was a wire brush. Once the seven bars were welded up and the edges ground clean and inspected, the procedure was - draw out to twice the length, hot cut in the center 3/4 the way through, brush off, flux and fold, weld, repeat. The billet was returned to the forge whenever it dropped to red heat. All folds and welds were at orange-yellow heat. The brush was used every time the billet came out of the forge. By never cooling off, scale never formed, and thus each fold was a good weld.
 
Sorry I never mentioned this but I do not have access nor do I have a press/power hammer this will all be done by hand. Stacy in your response to my question regarding San Mai what would you recommend material thickness wise and width for a simple San Mai billet? I don’t want to get too crazy in length either but I am not sure what is “manageable” if someone is doing this by hammer only.
 
[QUOTE="Stacy E. Apelt - Bladesmith, post:
You can use pieces about 6" long with a core of 1/8" to as much as 1/4" and sides of 1/16" to 1/8" and then draw the billet, or do it as a full length billet with .100 core and .060" sides. Getting a full length billet flawlessly welded up with no de-lams is a skill that takes some experience.[/QUOTE]

6"X1.5" is a good size. Try a 1/8" core and 1/16" sides to start with. Welded up that will be a bit less than .25" thick, which should draw out to 10" and forge to a good size knife.
 
Stacy E. Apelt - Bladesmith said:
[QUOTE="Stacy E. Apelt - Bladesmith, post:
You can use pieces about 6" long with a core of 1/8" to as much as 1/4" and sides of 1/16" to 1/8" and then draw the billet, or do it as a full length billet with .100 core and .060" sides. Getting a full length billet flawlessly welded up with no de-lams is a skill that takes some experience.
Click to expand...

6"X1.5" is a good size. Try a 1/8" core and 1/16" sides to start with. Welded up that will be a bit less than .25" thick, which should draw out to 10" and forge to a good size knife.[/QUOTE]
Thank you once again Stacy for your input. Your advice here has saved me from hours of frustration. I will be making an order here shortly from NJSB so I can get started with attempting to forge weld a few pieces and later attempt a San Mai but I’ve still got to walk before I can run so there will be plenty of trial and error but you guys have made it easier for me. Thank you once again:)
 
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