I want to try casting gold. I have a cut up 10K ring ( 6
gms) and want to add some 14K casting grain ( 3 gms ) to it. I
will cast a 7gm swirl ring. It is only for my owm use and not
resale. The reason for mixing is $$$. Any advice? Will the
color be OK?
if you do as you propose the color will be a little darker
yellow than what you have now.
why don't you just make it 10k or 14k? first, i would like to
point out that 9 grams (your present total wt. of metal) isn't
quite enough to leave an adaquate size button. a caster relies
on a button to push the metal into the cavity and feed more
molten metal into the mold cavity while the metal inside the
cavity is cooling. a too small button may result in some
porosity even if all ather conditions are correct.
second, i would propose to either alloy up to 14k or alloy down
to 10 k and be sure i have at least an 11,5 gram casting charge
for a 7 gram ring.
you need to add 4.6175 grams of fine gold to make your 10k into
14k. but this still only gives you 10.6175 g for your casting
charge, so add 1g from your 14k casting grain or all of it if
you could also alloy down. to alloy down, add 1.2 g alloy to
your 6g 10k and 3g 14k. but you still only have 10.2 g for a
charge, so you have to come up with 1.3 grams of 10k to make the
desired casting charge.
whichever option you choose, melt your charge together to insure
a homogenous mix of metal before you cast with it. if you can,
pour it into a bucket of water to get shot. getting shot is not
as important as mixing all your alloys together before casting.
even if i'm fabricating, i mix the gold and alloy together
first, pour it and cool it and then melt and pour the ingot
again. the metal behaves much better for reasons that are beyond
me to explain. see peter rowes superb post.