I attended a workshop this winter on mokume-gane. I would like
to keep working on this process. I was wandering if anyone out
there knew of any reason why I couldn’t use my burnout furnace to
fuse the sheets of metal together. Please send any other tips on
mokume you might have as well. Thanks for the help everyone.
Chris, Kansas City
Hello Chris! Having only limited experience with this
technique,my assumption would be that cuprous oxides (firescale)
would form before the metal would ever have a chance to
effectively bond. Too further your quest for knowledge in this
area check with Steve Midgett, who also does seminars. He has a
book and video on the process which I intend to purchase. His
website (all should visit, to see a well executed website!) is
http://www.mokume.com, his e-mail address is sm@mokume.com. You
can reach him by phone @ 1-800-374-6423.
If you can create a reducing atmoshpere in your burnout oven,
than it will work.But since you probably can’t you will end
wasting a lot of money on silver. I have seen mokume billets
that were made in non reduced atmoshpere gas furnaces but the
were fused w/ the aid of 20-ton presses. I have also heard of a
way to make electrics into kilns capable of producing a reduced
atmosphere but I do not recall the method and would be hesitant
to suggest it to anyone. Cyrus Niccore
You can use your burnout furnace. but keep in mind that you’ll
be driving that kiln at temps higher than normally used for
burnout. That may shorten, somewhat, the life of the elements.
Also remember that the atmosphere in that furnace is oxidizing.
Depending on what sort of arrangement you used in your workshop,
you may have to make adjustments to your procedure to ensure
reducing or at least neutral chemistry where the metal diffusion
bonding is taking place. A flux protective coat, for example, or
an enclosed pressure frame…
Peter Rowe
A friend and I experimented with kiln fused mokume and have had
good success with the process after some meltdowns. You need to
have a pyrometer and should recalibrate it with the temperature
pellets. We used only copper and sterling, two half-inch
stainless steel 6x6 plates drilled with 6 holes and secured with
stainless steel nuts & bolts under pressure from the hydraulic
press. We put the plates & billet in a cold kiln and heated to
1175 F in my enameling kiln (this is where your pyrometer
calibration is crucial and it may not be the same as mine) held
that temp for 3 hours and turned the kiln off. We experimented
3-4 times before we got the right fusing temperature for my kiln
and our altitude.
Donna in WY
Thanks for all the help with the mokume. I realize now that the
furnace we were using was firebrick and a large reducing propane
torch. Any oxide on the metal would prevent the sheets of metal
from bonding. The firebrick furnace wouldn’t cost that much to
construct and will save some heart ache and probably my burnout
furnace as well. Thanks again.
Chris, Kansas City
You can use a burnout kiln if you have a good temperature
control on it. I used a Ney kiln with a temperature control for
many years with good results. Most cheap kilns do not have a
control that will hold an exact temperature. To be really
consistently successful you need to hold the temp just below (50
degrees F) the melting point of the metals involved in the stack.
If you want more info I have a handout that I use in the
workshops that I teach. It is online at
http://mokume-gane.com/Workshop/Mokume_Workshop.html
All of my mokume laminates are made using a inexpensive
ceramics kiln and a digital controller that holds the temp to
within 2 degrees of the set point. Take a look at my site
http://mokume-gane.com/ and If you have any questions drop feel
free to ask.
Jim
@jbin
James Binnion Metal Arts
4701 San Leandro St #18
Oakland, CA 94601
510-436-3552
Thank you so much, Donna. This sound similar to the process we
used in the workshop. We used C-clamps to hold the steel plates
while we tightened the nuts and bolts. I was worried about the
difference in the reducing atmosphere in the gas furnace and the
electric furnace, but it sounds like you had some success at
this. I’ll give it a try. Thanks again.
Chris
Kansas City
Mokume is not hard on your burnout kiln. There is no burning
off of wax in the process which is what corrodes the elements in
the kiln. It will be operating at a slightly higher temperature
depending on the metals being laminated 1400 degrees for
silver/copper or silve/gold 1500 degrees for copper/brass . but
most kilns will operate at these temperatures for many years.
Gas fired kilns are very hard to control the exact temperature
in. Gas fired burnout furnaces even with the digital controls
that are now available for $500 to $1000 vary by 100 degrees or
more as the flame turns on and off. Without spending thousands
of dollars in metering valves and controls it is just too hard to
control the temperature very well. The process that is being
taught with a torch and fire brick kiln works well for small
billets. In it you look for a shine or flash on the edges of
the billet which is the very lowest melting point alloy formed
in the stack starting to melt. It is hard to make larger stacks
fuse this way due to differences in temperature in the stack.
With an electric kiln with a temperature controller you do not
have these limits. You can set up your materials put them in the
kiln and go to bed and wake up in the morning with your metal
ready to work on, and you can make billets as large as you desire
. The resulting laminate is a superior product as well. So try
an electric kiln I have been using one since 1983 it works well.
Again for step by step notes on the process go to
http://mokume-gane.com/Workshop/Mokume_Workshop.html
Jim
@jbin
James Binnion Metal Arts
4701 San Leandro St #18
Oakland, CA 94601
510-436-3552
When I learned to make Mokume Gane in a workshop with Steve
Dixon from Portland, OR at Highline C.C., we used regular
burnout ovens. We heavily coated the billets with yellow ochre
which helps reduce the oxidization, The only thing that I would
warn about is matching the melting point of the metals. We
ended up with one oven having a meltdown of Naval Bronze that
was a much lower melting point than the other metals. Fine
Silver and NIckel makes a beautiful Mokume but DON’T pound the
billet!!!
I don’t know that the higher temperatures involved are a
consideration…the burnout ovens are designed for a much
higher temperature than investment burnout and the time is much
shorter making Mokume but maybe someone out there knows more
than my resident Electrical Engineer housemate who says no
problem… Mine has endured 4 years of abuse…
Stella