When melting 24kt gold with nickel-white alloy, how do i know
everything is fully mixed together? I usually melt the gold first and
then add the alloy but do i need to turn up the temperature or look
for a color change once the alloy is added? Any help would greatly be
appreciated.
all you need to do is to insure that the crucible is well glazed
with borax if using a fused silica/clay crucible (if you are using a
graphite crucible the borax glaze doesn’t apply) then adding the
appropriate amounts of fine gold and alloy that you have weighed and
verified according to the karat you want in the end ( in your case
nickel- because presumably you are trying for a lower karat white
gold result ). WEAR EYE PROTECTION WHEN LOOKING AT MOLTEN METAL IN
ANY CRUCIBLE…When you pre heat the crucible and put the torch to
the metal and it forms a molten rolling ball you may use a stirring
rod of carbon/graphite not only to mix it well, but also if you
suspect there are any contaminants or leftover metal from the last
use of that particular crucible-contaminants will appear to be a
small black flake-like bit on the surface of the rolling ball of
metal. It is quickly skimmed off with the stirring rod while you keep
the torch on the crucible and maintain the temperature. You will
learn from experience ( rather quickly!) when the mass of molten
metal is “homogenized”, that is one completely rolling mass without
any striations on the surface or other indications the mass needs to
be further stirred -. It is really clear when the mass in the
crucible has melted together- I believe by the second or third time
you raise or lower a karat you’ll know when it has all come together
and is ready to pour into your pre heated mould or direct cast into
cuttlebone, tuffa, or even a plaster mould… You can’t really see
the colour change while the mass of metal is molten- it will simply
be glowing orange, as it is cooled and quenched into whatever liquid
( water or alcohol - most often water ) is appropriate for the metal
you are pouring you can see the result… Pickle if necessary,
neutralize ( with bicarbonate of soda and water), and rinse well as
you don’t want ANY acid remaining on your ingot, or rod when rolling
or drawing it as the acids will degrade your equipment’s rollers or
drawplates readily…rer
1) Do not use nickel as some people are allergic to it.
2) Melt metals according to the highest melting point.
I don't really follow #2, I just pour all the metals with borax in
the crucible and melt them, once they have been fully melted
(alloyed), mix them.
It’s not advisable to use nickel in jewellery, but there are
minimum allowances for it in Australia, 3% for external skin
contact, and 0.05% for piercing posts and other such pieces that
have intimate contact.
That’s interesting, however I always load my crucibles with the
lowest meltpoint metal, as this reduces the heat required to melt
metals. For example when i make my bronze I always load my
crucibles with the tin first, then cover with granulated copper. The
copper crusts up and seals the crucible, the tin melts, and the
copper melts into the tin. One of my friends does the opposite, and
loses a lot of his tin as vapour, as he dumps his tin into the
molten copper.
all you need to do is to insure that the crucible is well glazed
with borax if using a fused silica/clay crucible
When making gold/nickel alloys, the first thing to do is to lock
your borax in a safe. You are not going to need it. The only flux
used is boric acid. Dedicated crucible is of paramount importance. If
new crucible is used, then it should be glazed with boric acid.
Large torch is needed because only yellowish part of reducing flame
envelope should be used. I keep torch 2 feet away from crucible while
melting to insure that there are no free oxygen present.
While some stir alloys, I do not. When metal is liquid I shake
crucible using small horizontal movements of my left hand. The right
pouring temperature is when metal has shape of fresh egg yolk. I cast
my alloys twice to insure proper mixing. After first cast, ingot is
rolled very thin; cut in small strips; and strips are melted again.
Nickel golds must not be quenched, only air cooled.
I stir it & poke it with a graphite rod and feel if the alloy is
still there. IDK if it matters but I always let alloyed gold solidify
then stir, flux and melt it again before pouring into an ingot.
Large torch is needed because only yellowish part of reducing flame
envelope should be used. I keep torch 2 feet away from crucible
while melting to insure that there are no free oxygen present.
How big is your torch that it can melt gold from a distance of 2ft??
How big is your torch that it can melt gold from a distance of
2ft??
Smith casting torch will do it easily. You can also re-drill any
torch to larger diameter. You melting area is more important than any
torch. Get some firebrick to trap the heat around crucible.
Large torch is needed because only yellowish part of reducing
flame envelope should be used. I keep torch 2 feet away from
crucible while melting to insure that there are no free oxygen
present.
I missed that 2 feet ?!?!?!?! Wow, serious stuff CIA