Is there a way to pattern weld copper and it's alloys?

D

Dangus

Joined
Aug 12, 2000
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134
I realize copper cools extremely fast and therefore might not stay at the right temp long enough, but mokume can be made by basically taking it up near melt heat and letting gravity forge weld it together as the surfaces melt. Can it be work-welded?
 
The first time that I made Mokume I didnt know what I was doing and was experimentig,I learned real quick that you don't just hold the stack in a pair of tongs and flux the heck out of it,and when it is hot don't hit it real hard with a hammer:eek: I had the prettiest spark shower in the shop that day and you couldn't get away from it at all.It did go together though.Only big problem was that I had voids with flux in the piece when it was done.
Now as for your answer,Yes it can be patterned just like Damascus.There are guys out there selling it in all kinds of patterns.
I am not exactly sure how they are doing thepatterns myself.
You should be able to hammer it after you anneal it and just keep annealing it as it stiffens under the hammer.I hope someone else here can help on this as I would also like tho know myself how this is done.
Bruce
 
Mokume is like damascus, only about triple the things can go wrong with it. The temps get really tricky. I've done one piece of it with nickel silver, brass and copper. The layers of brass and copper fused and mixed because I got it to the melting point of the brass, but not the nickel silver. Here's the problem, though. Nickel silver is a form of brass, and brass doesn't take well to forging, whether it be hot or cold forging, and it has a different elasticity than copper, so delamination is a serious risk. My next step for the chunk that I made is to surface manipulate it, cut and stack it, then try to press it flat again while at near-melting temps. I put it in a stainless heat-treating foil envelope for this to prevent oxidization, but really you can just grind off oxides later. I'm just cheap and don't want to lose the material.
Then on to better materials. Brass was just a bad idea. If you can get bronze, or better yet silver, do it. Copper and silver have different enough melting points to make it easy, their forging temps overlap, and they make a really dramatic pattern because they look so different.
What were you thinking of mixing copper with?
 
Here's a link that may help you:to make mokume
I hope the site is still active....
Got it wrong first time, lets try again...okay, it's working.

Anyway, it comes down to the following: You need to use a electrical forge with accurate temp control. Work at approx. 20 deg below the melting point of the lowest melting point in your stack. Do not place nickel silver and any other copper alloy next to each other.
Use torque plates to keep the stack together. Every piece must be scrubbed with pumice and degreased before stacking.
Place the stack in the oven (you need to get any and all oxygen out of the forge by placing a few pieces of charcoal or titanium in as well) and let it soak for about 30 minutes. Take out, place on the anvil and strike two or three heavy blows. I use a flatter that fits betwen the bolts on the torque plates. Unscrew, reheat to red heat, forge down to about 1/2" Work in your pattern using drills. files, milling cutters. Reheat and forge flat.

For more info on metalworking go totheir homepage
 
Wow Tiaan, you answered my questions before I asked em. Thanks!!! I do have a couple left tho. Where do you get thin sheets of the materials to make mokume? I know you can buy shim thickness brass just about any place but I haven't seen copper or nickel silver anywhere. Is nickel silver a good metal to use or would sterling or coin silver be better? How bout 1/8" thick red bronze?Thanks for the help guys!!!
 
You guys that can make mokume are amazing to me. I have the same question as L6. I have checked out the mokume that reactive metals sell and they even use gold. Wow is it high priced!
 
You don't need a bunch of machines. Why does everybody always throw money at a technique? You can do it right it a charcoal forge just like it was made by ancient smiths. In fact I think its the easiest way. Probably becuase charcoal burns so clean. Mokume gane is not welded in the same sense that damascus is. You dont hammer it together. I take a stack of alternating layers of two non ferrous metals with very close melting points. I don't know why you cant put nickel silver next to another copper alloy, I have done it many times successfully. Copper and nickel silver work well but with the alloys close to each others melting point you can do even gold and silver. I make it out of 20 guage sheet cut into 2 inch squares. Each piece has to very flat and flawless to get the best results. You should work with rubber gloves and wash each piece with soap and water to remove all traces of dirt and oils. Then put the stack (I like 32 pieces) in a holding clamp that sandwiches everything together firmly with a long handle. Stick that in the forge and bring up the heat. Watch the corners of the sheets in the stack closely. What you are waiting for is to see one of the corners start to bead up. Then pull the stack out and examine it closely. Be sure to quench it before the color is all gone. The trick to getting good unions is being totally anal about cleanlyness during the stacking process. I messed up my first try becuase I didnt wear gloves becuase I thought as long as I washed everything under water with soap it would be fine. Nope. The oils in my finger tips ruined the joints. After you get a solid billet (no hammering required) you can develope the pattern. I drill various sized holes all over the surface of one side. Dont go deeper than half way. Then I gouge the holes together with a chisel type tool. Just making toughs from one hole to the next. Theres no set rules for patterning so you can just go for it as long as you dont go deeper than halfway. Then heat it up to a red heat and hammer everything flat. No flux is needed. All the holes and ruts you made in the billet will be pushed to the surface and become flat. Your billet is now patterned on one side and ready to use. I took some like this and punched a hole in the middle and forged it around a mandrel for seamless ferrules. These are very rare since most smiths take the flat sheet and bend it around and solder the joint to make a ferrule. Mine were seamless. I over simplified everything but thats should wet your whistle. Tim McCrieghts book "The Complete Metalsmith" has a good overview of the subject.
 
I did it in my homemade, backyard ghetto style propane forge. Electric would be nice, but anything with a pyrometer would be perfectly fine. As Tim pointed out, even judging by eye works well if you're well-practiced at it.
Here's what I did, pretty much in the order that I did it, in nauseating detail.
First I read a lot. McCreights book is good, Hrisoulas as always, lots of websites such as the ones already mentioned, and http://www.mokume.com , and I talked to several people that I knew that had done it. Aside from many people here on the forums, I also spoke with Steve Bloom, who has been helpful to me at every turn.
I gathered materials. Mostly from Ebay. Keywords that I looked for were "shim stock" and "copper foil". Kensimp has a pound of 22-30 guage copper foil up for auction on occasion, and is a great guy to buy from. I may have also bought the Precision brand brass shim stock from him as well, but I'm not sure. I also used some nickel silver that I purchased from the Blade show.
I made a small press out of 3/8" 304 stainless. I used four stainless 1/4" bolts from Home Depot. Galvanized anything doesn't go in my forge. I cut the copper, brass, and nickel silver to roughly the same size pieces. (Around 3" square) Put them in the press with a bunch of C clamps and squished them all flat, or at least flush with each other. Then I took them out of the press and cleaned them with a commercial "Professional" copper and brass cleaner. Then I cleaned all of that crap off with 220 grit sandpaper, using disposable rubber gloves stolen from the hospital.
Stacked up the pieces on a piece of cleaned heat treat foil and put a piece of broken pencil next to the stack, then folded the whole mess up into a nice, tight envelope in the press, as tight as I could get it.
Took it outside, brought the forge up to heat, and laid it inside. Took about ten minutes to get it to what looked like the temps it needed. I put a piece of copper foil on top of it all, thinking that it would melt at the right temp. This was a mistake. The foil oxidized and kept its shape, telling me nothing of value. Next time I'll use a chunk of the lower melting point metal.
When I realized my mistake, it was because of the color of the press. I knew I'd have to overheat a little bit because of the thermal mass of the press and layers in order to make sure that the center of the stack bonded as well, so I let it soak a bit longer at what I thought was the proper heat, then pulled it out, tapped it a couple times with a two pound hammer in the center of the press, and water quenched the whole mess. Took almost as long to cool it as it did to heat it up. Had to grind off the foil in some places, but it worked well. Due to the overheating and slightly too long soak times, the copper and brass fused and made a pretty red brass between the layers of nickel silver. Next time I'll suck it up and sacrifice the outer layers and not use the heat treat foil so I have a visual reference.
There you go, mistakes and all. Even an amateur like me can do this, if determined enough. My next try will be better.
 
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