Easiest Mokum Gane with HT oven

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Maelstrom78

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Sep 21, 2013
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Was wanting to use my new HT oven to make some mokume gane. My thought was to use the pressure plate method with some brass/nickel or copper/nickel so I have nice contrast.

I'm open to any suggestion, however.

What would be a good combination of metals (at what thicknesses) and time/temperature for a mokume newbie?

I would like to make some for bolster material and maybe some things for my wife and daughter.

Thanks!
 
Nickel silver and regular brass work well. Use torque plates and keep the biller small. Start with a 1X1X2" billet of eight .125" thick pieces. Put the whole plate in a HT bag with a small piece of charcoal. Follow the directions for doing the diffusion bonding method.

The book "Mokume Gane", by Steve Midgett is a great reference with temperature charts and more.

The biggest tip is to have everything freshly sanded and absolutely clean before stacking and bolting in the plates.
 
Thanks Stacy that is just what I am looking for.

Ok so the plan is to order the nickel silver and cutler's brass from Sheffield at the dimensions you detailed.

Sand each piece at 220 on the granite surface plate (maybe go to 400 after that for smooth surfaces) and wipe down with acetone and then rubbing alcohol with clean paper towels.

Place in the torque plates which either have been painted with white out, milk of magnesia or that have just been oxidized in the HT oven to prevent them from any fusion with the billet. Torque the snot out of them.

Heat in the oven for 2 hours (just picking that time- open to suggestion) with the torque plates wrapped in tool foil with a combustible inside and the plates torqued tight.

Temp at 1675F to be below the melting point of the brass. After 2 hours take out and let air cool (?) then bandsaw/grind the edges until I'm past any areas of oxidation between layers. I could just have my oven shut off after 2 hours and let the whole works cool off overnight as well.

Yellow Brass 1749 70% Cu, 30% Zn

Nickel silver 2030 65% Cu, 18%Ni, 17%Zn.

Another source recommends Brass with copper or nickel silver very bright orange 1830 F
temperature for the process but since that 1830 is above what I have found online that seems too hot.

Actually, on second thought maybe 1650F or 1625F would be better for heat since I am seeing a range of yellow brass/ other brasses with melting points in the 1650-1725F range I'm sure based on composition.

I'll put the whole works on a firebrick inside the oven and see if I have a billet or a melted blob!
 
Thanks I am looking for easy at first for sure! My thought is that I don't know how much patterning I will be doing from the get-go. I thought I would just let the normal shaping of the bolster reveal the layers.

For that should I use some thinner stock? Would .030 ish stock be too thin? I have that on hand already.

Should I just go ahead, bite the bullet and drill some holes and forge back to flat?

I'm exited to mangle up some metal for a while learning something new to me.
 
Ok per this online chart :
Fine Silver 1760
Sterling Silver 1640
Gold (24K) 1945 almost all gold alloys will work. 14K yellow should be fired at 1350°
Shakudo 1922 95% Cu, %5 Au
Shibuichi 1742 75% Cu, 25% Ag
Kuromi-do 1958 99% Cu, 1% As (This alloy is not safe to make in the studio due to arsenic content.)
Copper 1981 Oxygen-free alloy is best.
Yellow Brass 1749 70% Cu, 30% Zn
Do not place in contact with silver or high-silver alloys as it will melt (it makes silver solder).

Nu- Gold 1700 A Copper Zinc alloy (Jewelers Bronze)
Nickel silver 2030 65% Cu, 18%Ni, 17%Zn. Anneal often Do not quench


Sheffield lists their copper as a CDA 110. This site http://www.husseycopper.com/production/alloys/electrical/c-110-00/
states the melting point at the 1981 F So.....

If I am going for 50-100 F below the melting point of the lowest melting point in the stack - For Copper/ Nickel Silver I would run at around 1900 for 3-4 hours? How does that sound?

I'm using this page for reference. http://www.mokume-gane.com/Workshop/Mokume_Workshop.html

Thanks!
 
Yes, actually copper and nickel silver work easier than the white brass/yellow brass mokume. The copper has a lot higher melting point. It tends to darken a lot more over time than mixes with more "bright" elements. Another good combo combo is copper/nickel silver/brass/ nickel silver/copper/ ..... Once you have the process down, you owe it to yourself to do a 999 silver/pure copper billet. It has such a classic look when twisted.

You need to figure out the diffusion temp using a chart. It isn't just a guess. The time can be up to seven hours. A slow cool isn't what you want in my experience.

There are several ways of "setting" the bond of the layers. This step adds extra energy to the joints between layers, which raises the temperature there and fuses the layers. It has to be done carefully, as the metal can actually melt in the junctions and squirt out if you work it too hard. Here are a few methods:
You take the billet out of the oven and remove from the torque plate and gently hammer the surface from both sides. SAs it cools, increase the force of the blows.
You can put the bottom plate in a vise and torque the bolts down tighter. Then remove and do the above.
You can place the torque plates and billet in a press on a set of fitted flat dies and squeezevery carefully. Then remove and hammer work as above.

Once the billet has been "set", and cooled to black heat ( 900F), work it with the hammer or press all over. Try and reduce it by a third. Anneal and when it just gets to the dullest red you can still see ( about 1000-1100F), start hammering/pressing again. Reduce it another third. If it gets too stiff to work, re-anneal and continue. At the two-thirds reduction point you can manipulate the billet to get the desired pattern, and then work it down to final thickness. (Twist pattern is done differently, and too complex to go into here.)

Annealing copper and nickel alloys is done by raising them to above 1400F and then cooling to black. You don't need or want a slow cool. Just let it air cool to black and start working it immediately. If you want to work it cold, quench in water from black heat. Normally all reduction work is done below 900F. With some experience, you can start working it at 1300F while still red but if done too forcefully, it can smush the billet apart.
 
Ok Stacy thanks. I'll dive in and begin to learn.

If anyone would have a recommended starting point for the time and temp for a copper/ nickel silver mix I would appreciate it. Either way I'm excited to start.
 
My first and only go at mokume was using my electric oven and torque plates. i wrapped the stack in HT foil before putting it in the torque plates. I was able to get a successful weld, the problem arose when trying to draw out and pattern the billet. Thanks for posting the info on working the billet Stacy
 
The Steve Midgett books are out of print and the used ones are now priced at hundreds and thousands

I like this book, real scientific systematic approach of all metal combinations and photos of all patinas on all metals
41WKJX5D8EL._SX329_BO1,204,203,200_.jpg

ISBN-10: 0713661569
ISBN-13: 978-0713661569


http://www.mokume-gane.com/documents/SantaFePaper.pdf
 
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