I am trying to find a sauce for what the industry uses for
converting wax to cast gold - 9kt, 10kt, 14kt, 18kt & 22kt. Is there
anyone out there is a good source for this Seems like
every factory has their own version of this …all very
close, but no basis for the differences.
the calculation of the metal weight is straightforward and very
the volume you want to fill with metal is previously filled with
wax, therefore the volume to be filled remains the same.
If you know the density (sometimes referred to as specific gravity)
of the wax G(w) you’re using and you measure the mass of your total
(button, main sprue, sprues and models) wax M(w) then the Volume is:
which is the same volume for the metal.
With the specific gravity of your metal G(m) and the mass of the
metal M(m) the Volume is:
For the volume to be filled remains the same the ratio of M(m)/G(m)M
equals (w)/G(w). Therefore the Mass M(m) of metal needed is:
This applies for all waxes and all metals.
The density of your waxes and metals you may obtain from your
supplier or calculate by yourself.
Weigh the wax pattern with sprues attached and then multiply it x
the specific gravity of the metal you will use and then add anywhere
from 25% to 50% extra for the button.
The specific gravity of the following metals may help:
Karat Color Specific Gravity
18 green 15.9
18 yellow 15.58
18 white 14.64
18 red 15.18
14 green 14.2
14 yellow 13.07
14 white 12.61
14 red 13.26
10 green 11.03
10 yellow 11.57
10 white 11.07
10 red 11.59
pure silver 10.53
sterling silver 10.40
coin silver 10.35