Hi All. I hoping one of you can help me. I am trying to melt down my
sterling wire clippings (I have about 1 oz) for rolling into sheet
later. I put the clippings in the crucible and heated with my
propane torch (just the kind you get at the hardware store). I tried
the hottest part at the tip of the blue flame and I tried a bushy
flame (which seemed to work best, actually). The mass of clippings
has successfully fused together and I got occasional glimpses of
liquified silver, but it never fully became liquid or even close to
pourable. Then I tried adding some paste flux hoping it would help
flow, but it didn’t seem to make any difference. I don’t think its a
matter of time either as I was trying for about 1 1/2 hours. The
YouTube videos make it look so easy. Would gladly welcome any
suggestions.
I think that you will find that you do not have enough heat from the
torch to get the crucible and the metal hot enough to get the metal
molten. You need a good sized or high BTU output torch to get this to
work. The flame of your torch may be “hot” enough, but it is not
putting out enough “total” BTU’s to get the job done. This has been
my experience with this sort of problem, especially when not able to
see the size/total output of the torch in question. One has to
remember the difference between the temperature of the flame and the
BTU output. 2 totally different things but both are important…
Your torch just isn’t providing enough heat. You can try positioning
the crucible up against a firebrick, buy another torch and use it
with the one you already own, dump the crucible and use a hollow in
a carbon block (or charcoal.)
You can also try melting half of the material at a time.
the crucial question is…what type of heat source are you melting
with? Fact is that all silver has to be at the same temperature in
order to be fully liquid. Are you quiet sure that you’re dealing with
only silver items.
It might be worth it trying to melt a lower quantity of metal to see
if your heat source can deal with it.
My first quess is that your heat source can’t keep up with the
amount of metal you’re trying to melt.
BTW, a reducing flame with enough energy (flame with a yellowisch
tip) is used for melting silver. Silver can absorb about 20 times
it’s volume in oxygen caussing copperoxydul. A redundancy of oxygene
is a no go for melting silver!
are you positive it is true sterling ? if it is the new 40 something
percent nickle that all the retailers are passing off as sterling
coming in from overseas the melting point will be much higher and
that propane torch wont handle it. or if not you could try melting a
smaller amount of clippings and see what happens to test for the high
nickle alloy just take a small clipping touch it to a magnet, if it
sticks your supplier might owe you an explanation if not a discount -
goo
I’ve used my propane torch many times melting Sterling to make
ingots or to do Delft clay casting and it works fine.
However, I’ve used my biggest torch - not the one I solder with for
sure -
that will not get hot enough. I also used a few bricks as base and
with one brick on each side and one on the top to crate a small
chamber. It is my understanding this has helped - seems to focus the
heat somewhat - perhaps something you also could try.
You are simply not getting enough heat from the torch. I don’t know
what sort of torch you are using but you need a lot of heat to melt
that much silver. I now use a crucible furnace for my melting but
when I used a open crucible I used a Smith’s little torch with a
rosebud tip. At a pinch I could manage up to 40 grams with this
setup by surrounding the crucible with aluminium oxide wadding and
playing the flame inside the crucible. When I first started
centrifugal casting I used and industrial size propane torch running
on bottled gas. Both of these torches can generate a serious amount
of heat. Others use air acetylene torches or MAPP torches.
Hi Heather! Are you using a fresh propane tank? I’m still using one
and the flame can look big, bright and bushy but in reality bec
insufficiently hot!! Maybe try another type of torch from a hardware
store - mapps gas (yellow tank, propylene)? A big, fat, bushy,
hissing flame comes out of that sucker (smelly though and sets off
my smoke detectors from the heat).I’ve never tried liquifying metal
but do know that heat gets sucked away with some soldering blocks
etc…
Propane is not going to be hot enough. You can try a can of MappGas
(same can as propane only yellow, HomeDepot, etc.) Also, if you only
have the “pencil flame” nozzle even mapp will not help. You will need
to acquire the “blow torch” head. If you are using Bernsomatic you
can get this blow torch head online. If you walk into HomeDepot it is
only available with the kit that has the hose handle setup. I have
used this in the past with Mapp gas to melt up to 5 oz of sterling
for tufa casting.
JTH-7 or the current hose torch will work a treat with plain old
propane, but only if you contain the heat. Even one of those poxie
little hand held propane cylinders will melt silver in a micro
furnace.
It will melt with propane but you need a BIG flame to make up for
ther lower temperature. A disadvantage of doing so is it takes ages
to get hot enough and the flame spills so you get porosity in your
crucible and oxidation of the metal that will be difficult to get rid
of. Flux well if you are going down this route.