How to cut up a 5 pound ingot

I want to spend some time learning about casting (carving waxes,
sprueing, making and cutting rubber and RTV molds, etc.). In order
to keep the cost of practicing down, I bought some Lead-Free Tin
Alloy Casting Metal (Rio item number: 750042). It is a 5 pound ingot.
My limited, previous experience with casting has been with tiny
amounts of silver which I could easily cut up with shears. I don’t
know of a good way to cut up an ingot that size into small pieces
that I can put into a crucible. What is a good (easy and fast) way to
reduce that 5 pound ingot into small pieces?

Thanks.
Whit

A cold chisel and a hammer. CIA

I bought some Lead-Free Tin Alloy Casting Metal (Rio item number:
750042). It is a 5 pound ingot. My limited, previous experience
with casting has been with tiny amounts of silver which I could
easily cut up with shears. I don't know of a good way to cut up an
ingot that size into small pieces that I can put into a crucible.
What is a good (easy and fast) way to reduce that 5 pound ingot
into small pieces? 

I’d send it back and ask Rio to cut it up or trade it for manageable
shot.

hammer and chisel. use can also use a hydraulic press with a wedge
for the same effect.

you will contaminate your crucibles, so you do not want to use your
crucibles again for precious metals.

Mark Zirinsky
studio-z.org

Whit,

Cast iron pot on the outside grill or charcoal BBQ. Melt and pour
into deep (18") swirling water. Works for silver with a much bigger
heat source. Usual safety precautions least the safety nannys come
after me again. 500 F melt point so it isn’t too bad. Ya get grain
which is easy to use.

Other option for large chunks is an axe Messy and more work :slight_smile:

jeffD
Demand Designs
Analog/Digital Modelling & Goldsmithing
http://www.gmavt.net/~jdemand

not knowing the dimensions, a hack saw.

Hi Whit,

Chisel and a hammer. Metal cutting bandsaw if you have (or can rent)
one. Typically, those ingots come pre-formed into one pound lumps,
strung together sort of like a hershey bar. You could just try
breaking it off in a vise at one of the one-pound joints.

You are aware that this stuff won’t handle or cast anything like
silver, right? It’s intended for costume jewelry, and will melt at
some incredibly low temp. (compared to silver at 1700F.) It’ll also
contaminate all your tools, so you’ll have to clean your files & etc
before working on silver again. (The crucibles will be fatally
contaminated. You’ll just have to get new ones.)

From your note, you’re talking about “small sizes that I can put
into a crucible” which leads me to think that you’re thinking of
casting it as if it were silver. It’s not, and it won’t act like it.
There’s a reason those ingots are pre-notched into one pound blocks.
Costume jewelry people tend to do large loads, with a very funky
centrifuge caster that uses huge disk-shaped vulcanized rubber molds.
White metal casts at a low enough temp that you can shoot it directly
into a rubber mold. Very, very different beast than “precious” silver
casting.

If you’re looking for something “cheap” that does cast
(more-or-less) like silver, try Rio’s antique bronze. $12 per pound,
instead of $20+ per ounce, and no worries about contamination. It’s
not nearly as liquid as silver when molten, but it does have at least
a faintly similar performance envelope. (Molten silver flows like
milk. Bronze is more like maple syrup.) If you can get your molds to
work with bronze, they’ll be a cakewalk with silver. That tin stuff
won’t tell you anything about how the mold would work with a precious
metal.

FWIW,
Brian.

I’m not 100% sure it’s the same stuff but I took a casting class
this summer and the “pewter” we use was melted on a propane stove.
The ingot was put in a steel pan on the stove and melted much like a
stick of butter. In other words there is no need to cut it up.

If you like nice small pieces of bronze for casting send me an
email. I make thousands of pounds of bronze stamping scrap all nicely
copped and ready to cast. I’m happy to sell it to Orchidians for
right around the scrap price the local scrap yard gives me. I also
have Jewelry brass, sterling, titanium, aluminum, and various steel
alloys.

Jon Daniels
The Ring Lord Chainmail

Thanks for all the great ideas (and warnings)!

Over the long holiday weekend here a friend of mine told me he has a
friend with a metal cutting bandsaw. I’m going to see if I can get
him to slice it up for me.

Thanks again for all the ideas and advice.

Whit