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High-Performance Blades Sharing ideas for getting the most out of our steel.

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  #1  
Old 01-11-2009, 09:02 PM
SIXFOOTER SIXFOOTER is offline
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Complete Noob question on melting NS

ok, I am looking into making bolsters and pommels with Nickel Silver. Not knowing anything about the subject, I am trying to figure it out.
So, I figure you need a forge os some king, working on that.
Next I need a Crucible? what size type?? Ebay prices from $10 to $50
SO I figure I need a mold of some kind, lost wax or whatever. I am looking at that too. Lets assume for this thread I have a mold (right!)
OK, on to the material, What constitutes NS? Percentages? Are they important? What kind of temps are we talking about?
Do you mix your own recipe? off the shelf bars, ingots, coins?..
Thanks for helping me understand guys.
I am waiting on more grinder parts so until those get here I am trying to explode by brain in other areas.
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  #2  
Old 01-12-2009, 09:07 PM
Doug Lester Doug Lester is offline
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Nickel silver does not lend itself to well to casting due to it's high melting point, greater than 2000 degress depending on the exact alloy, according to Tim McCreight in his book "Complete Metalsmith", professional edition. It also has a problem with oxidization which will cause bubbles in the metal. In either plastic or wax loss it would have to have a special high temperature investment.

You might want to consider aluminum. It melts at 1220 degrees F., lower if it is an aluminum alloy. At that temperature you could use several things for molds, not only traditional investment but also things like plaster of Paris, charcoal blocks, and cuttle bone. The metal can be poured into a mold cut into a solid block, which could be the plaster of Paris, charcoal, or cuttle bone. It could be cast into a cavity made by pouring an investment material around a distructable model that is burned out of the mold as in wax or plastic loss casting. There is also sand casting where oil or water treated casting sand is packed around a durable model and the model removed and the sand shell put back together before the metal is introduced into it.

To digress a little, the neat thing about plastic loss, the model, which is made of the type of styrofome like the florists use, gets burned out when the hot metal is poured into the mold. Plaster of Paris can be used because the mold doesn't have to stand up to the temperatures in a burn out kiln.

Most of us don't cast our bolsters or guards but grind them out of solid bars, which can be done with files. You don't have to have a grinder to do it. Forging techniques also can be used. If you do want to cast your bolsters and guards, I'd get a good book on casting. The one mentioned above my McCreight deals with more than casting but will give you an overview of the various casting techniques. I advise that you get the professional and don't waste your money on the student's edition. The former gives more information and the price difference is rather small. Whatever you do, learn enough about the techniques that you want to use to stay safe. Getting splashed with molten metal would probably ruin your day.

The only cast bolster that I have done was a poured bolster out of babbet metal, a form of unleaded pewter, that I actually poured directly onto the knife in a mold made out of masking tape. Didn't come out too bad. I got the babbet metal from Roto Metals; it's listed with their pewters. It is a little more expensive than the other lead free pewters but it is pretty hard which I learned to my displeasure when I had to cut my first attempt away from the knife after a bad casting job. I melted the metal in an iron ladle over the stove. The knife was held in a can full of horticultural sand that I had laying around from another project and I protected the counter top with a 1' square ceramic tile. Roto Metals also sells ladels. Anyhow, this should give you some things to consider.

Doug Lester


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  #3  
Old 01-14-2009, 06:20 PM
SIXFOOTER SIXFOOTER is offline
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Thanks a lot Doug!
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  #4  
Old 01-26-2009, 05:55 AM
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Crex Crex is offline
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Hey Doug - little pointer on the babbet and other pewters. Get one of them old timer large plumber's soldering irons. You've seen them, big wooden handle, heavy 3/8" tip, cloth braided power cord, etc. Get one at a flea market or estate sale (not seen one in a catalog anytime recently). They have enough mass and get hot enough to melt the pewter away from the handle and blade without damaging anything. Have to be patient and careful but works very well and you get to keep/recycle the pewter and reduce the risk of doing damage to handle or blade.
If you peel your "mold" of right after the pewter sets you can see if it's flawed (have the iron already up to heat before you do the initial pour) and while it's still hot it will melt off quite easily. A regular sized soldering iron won't get it, not enough heat/mass ratio.
You can also use the iron to "pull up" the sunken or shrunk area against the blade due to temp differential right after the pour, with a little practice.
It can also be used to fill those (always happen when you least expect it) pin holes. Just a good grade of low-temp silver solder and the iron will plug a hole and make it invisible.


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Old 09-14-2012, 11:07 PM
winndhook winndhook is offline
 
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Being a Welder and Welding Teacher, I always have pieces of brass brazing rod around the shop. I stripped the insulation off some salvage copper house wiring and brazed the twisted copper wire into flat (ish) strips about 1.5 inches x 12 x 1/4 to 3/8 " thick. By hotworking the flatbar, (I won't call it true forging by any means), I came up with a imitation Mokume that looked deadly. With some grinding, it looked like meaty bacon with copper running through the brass in uneven bands. It's not a five minute project, but the bolster material looks deadly almost every time, far more appealing IMO than brass or stainless steel. As the copper darkens over time it looks even better contrasting with the lighter yellow brass. I didn't like the price of brass flatbar for bolsters, this experiment solved the problem with a nice exotic look
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Old 09-15-2012, 04:43 AM
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Crex Crex is offline
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That's pretty much the same as mokume, just made up dimensionally different. Sounds like some pretty interesting material for guards. I have "Braze-dipped" fine steel cable to get a twisted steel/brass pattern a few times. Have also stacked, heated and smacked quarters together for a type of mokume.
Are you using any kind of flux to get the bond between the two? ie- flux still on the brazing rod.


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blade, bolsters, brass, flat, forge, forging, grinding, guards, knife, made, material, pattern, project, rod, stainless steel, steel


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