Reheating damascus

Sam Salvati

Sam Salvati

Joined
Aug 6, 2007
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Ok, this is a whole intimidating scary thing for me, DAMASCUS!!!!:eek:

To be honest, in my limited expeirience, it scares the heck out of me. I don't know what it is, fear of failure, fear of the unknowing. the fact that I could very well spend a great bit of time and end up with a tiny cold shut or other ruination. But phobias aside, I wanted to ask about something I have seen more than once now. I have some ideas as to why, but as I have little to NO experience with damascus I figured I would ask those who do.

I have gotten some small bits and pieces of some other maker's damascus, and have given forging them a try. These are some high end makers damascus. Almost every single time I have tried this the pieces have come apart along the welds. I usually put the pieces in the fire under low or no blast heat/flame, and let them come up to red temperature slowly, then heat from there up to forging temperature. I bring them out at a mid yellow and give some light taps at first then slightly harder then they come apart. they do not crumble, they just come apart. I know it is not a flaw in the damascus itself, should I be fluxing? Am I overheating? Underheating?

I managed a billet of mild steel and 1075 once before. The only successful damascus type work I have ever done, and I am getting the jones to start working with the billet I ended up with again very badly, and I do not want some horrible catastrophe to just occur when I could have solved it easily with a bit more knowledge.
 
Sounds like maybe there wasn't very good fusion Sam.

My first suggestion was going to be to get it hotter, but it sounds like you got it plenty hot. Just make sure not to keep hammering into the real low temps while you're blocking out the blank.

Especially with mosaics, it's not hard to get dellaminations if you keep beating the snot out of it, after it's not hot anymore.

I hope to see pics when you get that steel worked up into something :)
 
Thanks Nick! I am not hitting below a mid orange, I am making sure to work it nothing but hot. It would just literally come apart into little squares and chunks as if I had a little stacked up billet, then just tipped it over and let all the pieces fall onto the anvil. I have not had this problem with my bar, as I have not reheated it from the original welding and drawing session, I have only had this with other's damascus.
 
Sam,

Was it mosaic? From the sound of it "coming apart into little squares" I'd guess so. Mosaics can be a little delicate along the final weld boundaries, especially if there was not a lot of stock reduction after the final welds were set. Most of your standard random, twist, etc won't have this problem.

-d
 
Hi Sam
what was the mix? if they're very dissimilar materials then its easier to delaminate..

Nick is right on ... hit it while its hot.. ( but not too hot... can get crumbly if O1 is in there )

try using 1084 and 15n20.. you'll like it... trust me

Greg
 
It was not mosaic, the pattern was turkish twist. Steel was W1 and A203E I think. That was the other damascus I didn't make, I was just trying to forge it.

So you do not think I will have any problems (considering any thing else like an incomplete unseen weld) with the mild/1075/mild sandwhich I have when I want to continue forging it, as long as I work it hot?
 
this brings back memories of my first Damascus welding experance. i had it up to heat and had made my first weld along the whole length of the bar. then i split it in half and did the same. then on my third fold over i got half way through welding it and my forge ran out of propane. i panicked, I put the bar in the forge and shut the doors. and ran to the computer and posted my problem on a knife making forum, might have been this one. i quickly got a replay that told me don't panic, just get more gas and start where you left off. i ran to the store got a refill and continued to forge. O fun times
 
Sam Salvati said:
It was not mosaic, the pattern was turkish twist. Steel was W1 and A203E I think. That was the other damascus I didn't make, I was just trying to forge it.

So you do not think I will have any problems (considering any thing else like an incomplete unseen weld) with the mild/1075/mild sandwhich I have when I want to continue forging it, as long as I work it hot?
Click to expand...

Turkish twist is again one of those patterns that can be tricky since after the final weld you don't want to do much to it and risk deforming the pattern. Consequently, it's tricky to get right.

I think your initial billet should be fine barring any unseen evils that lurk within ;)

-d
 
Ahh ok, cool, thanks for the help.

Could it maybe have had something to do with the fact it had been etched beforehand?
 
Sam, turkish is small mutiple bars of twist, stacked up and lightly welded together.
It should not be re-forged, unless at a welding heat with flux and the pattern would be really messed up.

Etched or not shouldn't matter.
 
Sam,
We all screw up a bar of Damascus from time to time. I have to chalk it up to a learning experience and try to change my process to prevent it from happening again. The first bar I messed up I had work on by hand for almost 2 weeks. I was at my final 2 folds, using a coal fire. Walked 10ft away with the blast still blowing. Gone for about 30 seconds when i got back the billet was sparking like the fourth of july. The Blacksmith I was working with just laughed and said start again, then what did you learn?? Messing up is why we are so anal about keeping the welds clean and the fire hot. Also it is why I have gone to dry welding almost 100%.
 
Well you see I start with 16 pieces of material..... Nothing fancy, I use a can were it will benefit. I weld up seams when that is easier. When I do an initial weld on a stacked billet I weld up mild steel on the sides to make the box. I do not need to weld up all the seams this way and get really great results. But I do remove the mild steel before pressing from the sides. It takes a little longer than wet welding and prep is absolutely critical. But for close to 100% success rate I will take the time.
 
Dry Welding, I have heard of that but would never dream of trying it yet :)! Maybe if I still had a welder.

Deker, thanks for the help :thumbup:
 
One of the more fascinating things I have seen is the micro I made of one of my forgeweld composites. There is carbon migration from the 1095 to the wrought iron, but what is really fascinating is the transweld grain growth. I was showiing it to one of the senior metallurgical engineers, he told me if I keep thermal cycling it I will keep my grain size about what it is, but eventually the weld zone will diffuse enough that I will have for all intents and purpose a continuous grain structure across the weld which will remove most of the inherent weaknesses of the weld zone. I would experiment with a small amount of the billet, flux the hell out of it, and soak it at just a little below weld heat for a couple hours.

just a thought

-Page
 
Sam,

See if you can find someone with a Mig welder. This is the easiest welder to use for dry welding. Though I have not done micrographs of the dry welding process, you can see, or actually not see the difference at the weld zone. This is what convinced me to try it. When you flux the snot out of it you can see a huge diffusion zone between the welds. Tom Ferry showed this to me and is the one who explained and convinced me to go for it. I have played around and tried to hurry the process byt not dry welding some of the folds. I almost always pay dearly for it. The more anal I get the better the weldment. When I just angle grind the surfaces clean and weld up all the seams I get good results. When I mill them all flat and weld the seams I get great results. When I mill then surface grind all the pieces I get phenomenal results. This is what I normally do for my final welds, esp on mosaics. Like I said it takes longer but it is worth it in the end.
 
WOW Chuck, that is getting anal! :D I remember seeing some pictures of flux welded and dry welded seams, and the difference was amazing! Especially with the mosaic pattern stuff.
 
Well now I've got a lot more to think about...thanks guys :)

I usually do leave billets to soak in the forge for 5-10 minutes after welding on the assumption that the cross-boundary grain growth will help hold the weld. So far it has helped reduce weld failures. Interesting to know that the theory may have been right ;)

-d
 
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