New Member Getting into Mokume.

[GinZaikuShi]

New guy here, just getting into the production of Mokume Gane

 

My blacksmith friend and I have been talking about getting into the production of Mokume Gane for a few months now, and a few days ago we tried giving it a go.  Our first (semi-successful) piece was done with the tried and true stack of quarters, which we forge welded and folded like Damascus.  I say semi successful, because it was the only piece with a visible pattern.  It was also full of cold shuts and imperfect welds.  This piece was done inside a wood fire, which is far from ideal and what i think had a lot to do with the poor welds.

 

 

20 attempts later, I tried for a new technique.  This time, we were able to get an even weld all the way through in one heat, and didn't have to flatten the disc so much.  I believe I will be carving or drilling into this piece and flattening it out on a roller.  It's a little over a troy once of two grades of sterling silver, welded.  Sorry about the bad picture.  I only had my cell phone with me at the time.

 

 

So, I have some questions, now that I have a pretty good method of producing this stuff.

 

How much could a sheet or ingot of silver/silver Mokume Gane be sold for to a jeweler?  I live in an area with tons and tons of Jewelers.  I talked to a silversmith that my friend apprentices with, and she said that (as far as she knows) no one in the local area is producing Mokume Gane. 

 

Should I anneal this piece of Mokume before carving/drilling and flattening?

 

Does anyone have any suggestions for cool silver patinas that could make this contrast pop a bit more?

[Chinobi]

Do yourself a huge favor and pick up a copy of Ian ferguson's book on mokume game, it's probably the best text short of steve midget's 'a comprehensive study' (which is next to impossible to get reasonably, but might be had through the library system)

Ferguson has an entire chapter dedicated to patination and another to patterning techniques (not to mention bonding theory, combinations, etc etc)

With a combination of two silver alloys (which, btw?) you may end up having trouble getting sufficiently distinct results because of the common metal. Of course If the alloys are different enough it might work. Skim through the entire mokume section, and the finish and polish subforum to see how much of this has already been covered.

Really difficult to say what the value will be, especially if you are just some random guy offering it to a jeweler. You need to be able to prove the content of what you are selling so they know what they are buying and don't feel like you are trying to sell them poor quality metals. They also have no proof of how well or poorly your bond has taken, so that could be a separate hurdle in itself.

It does look like you are getting some good results there though, keep up the good work and keep the pics coming!

(phone post, autocorrect willing it makes sense :) )

[GinZaikuShi]

The silver alloys look very different to me, i'll have to get a better picture.  One is 90/10 silver/copper, and the other is 40/60 silver/copper.  I basically applied the quarter style mokume to silver clad JFK half dollars.  I found out though, after melting a stack of three, that forge welding wasn't going to work for silver....haha.

[Chinobi]

i dont think you have the right numbers there.  the early JFK's were 90/10 silver/copper but the next generation (1965 til 1971) are nominally 40/60 copper/silver, but thats the total percent, its actually two alloys kind of like modern quarters and dimes are clad, but i think the edge is covered rather than sandwiched.  thats why there is such a difference in the layer color, because the cores are 79% copper!

 

that does however open the door a little wider to patina potential as there should be a significant enough difference between the metals to give different results for the more copper heavy alloy vs the silver heavy alloy when subjected to whatever patina you end up applying.

 

no idea how those particular alloys will handle, but silver generally doesnt like to be worked hot, once you have established the bond let it drop to black heat and then have at it.  anneal the stack before you start to work it, you want it soft so you can work it longer before it work hardens and starts to get brittle.

 

i dont know if any jeweler is going to want to bother buying raw materials made from coin grade metals, especially if they are mixed in less than certain quantities.  they cant readily mark the content so reselling becomes problematic.  the high copper content will also tarnish more easily than sterling silver (92.5% silver) which is not a good thing for jewelry as it requires more maintenance, and if it isnt backed by sterling or fine where it contacts skin it can start to turn said skin green :)

 

forgot to ask what general region you are in as well, there might be other members lurking in the neighborhood and local prices can vary quite considerably for things.

 

http://www.coinflation.com/coins/1965-1970-Silver-Kennedy-Half-Dollar-Value.html

straight boullion value for the nominal 40%(1964-71) coins is around 3.50$ each

 

http://www.coinflation.com/coins/1964-Silver-Kennedy-Half-Dollar-Value.html

the 1964 90/10's are about 8.60$ just for the metal at todays market prices

 

depending on the condition of the coins in question they can be worth 10$ or more as coins

 

with silver at 23.85ish/ounce i (as a coin collector) would be more inclined to just buy clean new stock and stack it against pure copper or maybe a brass or bronze to get a much more dramatic contrast without consuming the coinage :)

 

out of curiosity what procedure are you using to bond them?  i think you might have introduced a potential source of failed welds by trying to fold your original attempt(s) like damascus, copper alloys are really reactive and oxidize extremely quickly, especially when hot.  if you want to bump up your layer density try cutting the stack in half or quarters cold, clean, clean (did i mention clean!?) the faces, restack and rebond like you did initially.  that way you can limit the amount of oxide penetration between the layers and get a better bond.

[GinZaikuShi]

My current procedure goes as follows:

 

Clean coins, sand to 600 grit, clean again with iso alcohol.  Bind coins between two steel plates and tie with bailing wire.  I fluxed between all the coins and between the coin stack and the steel plates.  Put ceramic tiles on the outside of the steel plate/coin stack.  Then put that whole stack in the post leg vise.  Heat until sweat and compress. 

 

That's how I did the silver, no folds.  I thought my welds were pretty good.  When I dropped the cool stack on a table, it sounded like a solid mass.  No clunky cold shut sound.  But when I went to drill it today, I broke a weld.  Attemped rewelding it, and it seemed to work.  I carved it instead of drilling, but messed up some welds during the flattening process.  Really should have found a roller instead of trying to hammer flatten it, I think.

 

My friend and I built a gas forge today, so I think I'm going to try that out tomorrow.  Also, I'm in Asheville, NC.

[Chinobi]

skip fluxing between layers IMO, just adding potential for the flux to become the garbage that gets trapped between layers.  you can flux the edged for good measure, that wont hurt anything but its not mandatory.  similarly dont flux between the stack and the plate, if anything that will encourage bonding there rather than prevent.  get some whiteout and paint the steel plate where your stack will contact it, you can put a little square of paper in between as well.  i have heard yellow ochre works as a good antibond as well, but i havent used it myself.

 

cant say why the welds didnt take, but i think doing it in a gas forge will be a much better environment for heat distribution and less available oxygen.  you can toss some coal in to help consume a little more oxygen too (not briquettes).  running the forge a little on the rich side so long as you can maintain heat will also provide a better environment for the bond.  every time you rotate and flip the billet in the forge remind yourself not to remove it from the flame as well, taking the billet out of the fire before the bond has occurred is inviting oxide penetration and failure.

 

flattening with a hand hammer is do-able, be patient when flattening, you dont need to do it all in one swing, this puts less stress on your welds.  make sure your patterning grooves dont have any vertical sides or sharp V's in the bottom too, thats a set up for cold shuts and cracking when you go to flatten.

[GinZaikuShi]

Made a Mokume ingot today, and everything went perfectly.  We welded up a stack of dimes in the gas forge,  Traditional style, between two steel plates bound with bailing wire.  I took your advice.  Kept everything very clean, no flux, and a bit of paper between the plates and the stack.  After the coin stack was welded, we hot worked it and drew it out into a square (ish) stock ingot.  The stack appeared to get denser and stronger during the hot working process.  No problems with cold shuts.  We had a couple broken welds that were rewelded easily in the forge.  The dime stack was pretty crooked during the weld, and gave the finished piece a nice wood grain type pattern.

 

Will post up some pictures tomorrow.  I'm so psyched!

 

My friend and I are looking to mechanize the process a bit.  The one ingot, about 15 grams, took most of the day to make.  Certainly not worth the amount of labor at this point.  I felt like things should be done by hand though, until we had a truely sucessful finished piece.  We're looking into building a mini hot roller first, since I have an old sewing maching motor hanging around.

[Chinobi]

oh man, dimes? thats a lot of work for a tiny little billet!  make yourself a larger stack so all that labor will net you a larger finished sheet or bar for twisting, or ingot, blah blah.  hats off to you for getting a stack of dimes together with just baling wire holding everything together, that would have been a mess if i did it im sure!

 

great to hear that you guys are having success with this :) keep an eye on those re-welds though, they can seem like they rewelded but its just at the edge and as you work it they will split again.  its not unheard of, but iv not had much luck with rewelding partial splits because you just cant get in there and clear out the junk =/

 

cant help you on the machinery side of things unfortunately, but there is a section of the site dedicated to it, and i have seen a couple of different sets of plans/instructions for home grown rolling mills.  so have a look around and you should be in good hands.

[Steve Sells]

the bailing wire can not be keeping presure on the stack. When the wire heats it looses too much suppport ,  try clamping then bolting it, that will hold more force than stretching wires.

[Chinobi]

it works well enough on larger billets, especially if the plates are fairly massive.  definitely not as much pressure at working temperature as bolted torque plates but it wont immediately fall apart.  also helps to make a little containment box from thin gauge steel to really keep it together.

 

that said, I do my coin billets with bolted torque plates but without the sheet metal box/sleeve to keep it together, so I gotta make sure those bolts are really cranked up tight!

[GinZaikuShi]

the bailing wire can not be keeping presure on the stack. When the wire heats it looses too much suppport ,  try clamping then bolting it, that will hold more force than stretching wires.

 

Haven't had any trouble with the bailing wire so far, as long as I can get it welded in the first heat.  I'm working on making a torque plate though, just have to get some bolts.  I have zero dollars to put into this as of yet.  Even the roller will be made with just what's laying around the shop.

[GinZaikuShi]

Pictures!

 

Here's the dime ingot.  Just a wee baby ingot, about 2 inches long.  I like the simple, kind of wood grain pattern.  I may give a go at twisting it though, since its nice and drawn out.

 

 

Also scored these from my girlfriend's change jar. Two 1964's, 90% silver.  Won't be using them for Mokume though, just for the junk silver coin collection.  I've got a stack of 9 copper half dollars that will become a larger version of the baby ingot tomorrow.

 

[Chinobi]

very nice ingot there! I love that look :)  if you twist it and split it in half with a jewelers saw you can get the ubiquitous star pattern, or if you turn that into a split cross blank you can forge one that looks very much like it was made out of real wood :)

 

nice score on the coins there, they look a little circulated but otherwise in good shape.  and if you destroy them I will no longer speak to you :ph34r:

 

good call on the copper/nickel clad version though, I have a pile of those sitting around my house somewhere and totally forgot they are the exact same composition as quarters.  iv been branching out to international currency lately as I have a huge pile of odds and ends coinage from all over the world.  turns out a lot of the English coinage is good stock metal for this so long as they are early enough (I think 1981 and before, but that's just from memory so look it up if you plan to use them).  gotta make sure they are the right years because they switched their small value copper coins from basically a 97% copper content bronze alloy, to copper jacketed steel, which would be quite a surprise to try and forge out in a mokume stack XD

[GinZaikuShi]

I'd really like to give it a twist, I'm nervous though. haha.

 

I have a huge bag of old English pennies, the big ones.  I think i'll stack them up with some of the brass sheet scrap I have.  I'd like to find a good source of Nickel-Silver, I think it would be a lot less tempermental in the forge than sterling.

[Chinobi]

square it up a little so you have a flat surface to grip on, get it hot and twist it up :) move quickly from forge to whatever set up you have to twist with though, tiny little billets like that don't hold heat at ALL.  don't rush the twist either, take it in multiple heats if you need to.  and don't be put off if it ends up fraying apart :) it happens, chalk it up to learning and see what you can do differently next time.

 

nickel is a little stiffer, but you can work it red.  try not to let it soak at heat once the bond has set or you may start to lose the distinction between the copper and nickel as they diffuse into each other readily and can actually create microscopic porosity (if memory serves, I don't have the time to look it up, Kirkendall Porosity is the name if you want to google it) which at best will fuzz the boundaries or introduce kind of a third color, at worst can lead to bond failure.

 

as for getting ahold of nickel, you can buy sheet from a variety of sources online, or perhaps if you have a sack of English pennies you may have a pile of English 10/20/50 pence as well? pretty much all of the small denomination English 'silver colored' coins are 75% nickel/25% copper IIRC from looking this up a few weeks ago.  there was one notable exception that was a much higher nickel content or was clad in an interesting way, ill look it up when I get home.

 

again, the mint date is important when using coinage, for example the 10 pence coin has been nickel plated steel since 2012 (I think the rest of the 'silver colors' changed at the same time, only looked up the 10p right now)

 

doublecheck what you have in terms of the pennies as well, 1992 and later are steel core :)

http://en.wikipedia.org/wiki/Penny_(British_decimal_coin)

[GinZaikuShi]

Almost all the coins I have are pre 1960.  The pennies I have are mostly from the 1880s to the 1940s , they switched to the small pennies in 1971 when they decimalized the currency.  Want to grab any before I melt them down, Mr Coin Collector? haha.  Maybe I should sell them off and buy some sheet stock.  There's a sheet metal suppier across the street from my shop.  I was also thinking about using some Euro and Lira that have the two different colors in one coin.

 

I'm wondering also, if nickel and copper etch at different rates.  I'd like to make a twist billet and put a long, deep etch into it.  I've got a big batch of Copper Chloride that I mixed up for another project.

 

As for the JFKs, circulation doesn't mean much to me.  I save them for the junk silver.  I coin roll search here and there.  I've got a nice collection of War Nickels and a few silver dimes and quarters.  Didn't pay a thing for them.  I used up all my 40% JFKs making jewelery. haha

[Chinobi]

Lol, you are killing me XD sell off the valuable ones if they are in good condition and buy new metal IMO :)

Iv thought about those brass/nickel donut coins too but I haven't tried, methinks the seam between metals will cause problems come flattening time, but worth a shot :)

Haven't used copper chloride, vinegar or scalex(jewelry grade muriatic (HCl)) will do the job. The copper will etch faster, you only need to etch it a bit to generate a nice distinction in surface finish. You might need to break out something stronger if you want a topographic (deep) etch

[GinZaikuShi]

Copper Chloride is the only thing I've really done any etching with.  It's cheap (Muriatic + Hydro peroxide + copper shavings), and one batch is a lifetime supply.  I used some to etch my buddy's maker's mark into a copper stamp.  Took about 3 hours to get about a half mil deep.  I know it's good to use on copper, brass, bronze, and nickel, but I didn't know about different metals etching at different rates.

 

I love the look of this deep etched lighter.

 

[Chinobi]

i dont know much about the copper chloride, but a cursory googling doesnt return much of an intended use as a mordant.  you would be well served just using the HCl alone :) just looking at the procedure to make it; if the intent is to dissolve solid copper you have already reduced its effectiveness by loading it with copper shavings beforehand. (IMO anyway, seems like trying to dissolve a large chunk of rock salt by using saltwater)  

 

if my chem is worth anything after 9 years (has it been that long? O.o) dissolving copper with HCl looks like: 2H(+) + 2Cl(-) + Cu(2+) = CuCl2 + H2, but you already added a bunch of copper to generate the CuCl2, which has subsequently consumed a percentage of the free CL- ions from the HCl.

 

Thats a pretty awesome piece too!

[GinZaikuShi]

I won't claim to know any chemistry, I was terrible at it in school. How it was explained to me, was that the mix is unstable until a bit of copper is added.  Apparently it produces a bit of chlorine gas.  So a few shavings are added right off the bat to stabalize it quickly.  Like I said, I don't know though.  Most of this info came from a second year chem student, who thinks I'm reckless. haha.

[Chinobi]

id still just use the HCl solo :) apparently the H2O2 is releasing the extra oxygen (which is what it is known for), which is taking the hydrogen ions in the acid to produce H2O, which leaves the free chlorine to pair up as Cl2 (chlorine gas) which is not good stuff!  even with just the HCL and copper I believe the bubbles produced are hydrogen gas (flammable :), though small quantities) so good ventilation is critical no matter what the recipe.

[Chinobi]

ok sorry, i got my percentages backwards on the english 'silver colored' coins.

 

the exception is the 20 pence coin, which is 84% copper and 16% nickel (1982 to present)

 

the rest of them are 75% copper and 25% nickel, not the other way around.  they switched to nickel plated steel in 2012.

[GinZaikuShi]

Ah, so they're just like our 5 cenbt pieces.

 

Sucessfully made a quarter billet today, shaped it and flattened it into a sheet.  My production time is going down slowly, but surely.  Also took the little dime billet and gave it a twist.  Will post some pictures tomorrow, in the day light.

[Chinobi]

yes, very similar to our nickels.

 

kudos on the quarter stack, looking forward to the pics :)

[GinZaikuShi]

Do you have any suggestions on silver/copper mokume?  I've been trying to do it the same way as the nicke/copper stacks, but it just isn't working.  Even the slightest tap from the hammer is squeezing out the silver, and I can't seem to keep it at the right temp.  It's always too hot.  The silver smith my friend works for ordered a couple 1x3 20 gauge pieces of silver/copper, and said she would put me in contact with her other jeweler friends, if it went well.