Thank you very much for your help. If I interested to cast 10K
white gold ( with nikle) diamond ring , would you please recommend
me the flask temp., metal temp., and other technique that it's not
harm the diamond.
Sorry Lek, You’ll have to do your own experimenting with 10K, etc. I
don’t cast in that gold. No matter what you do cast, you don’t want
to burnout higher than 1100 Fahrenheit because beyond that, you might
burn your diamonds and get a white, dull film on them that would have
to be polished off by a diamond lapidary expert. When you’re talking
about melee, that would be cost prohibitive.
The casting temperature for the metal is a matter of your casting
technique, what type of castings (filligree, fine detail, heavy men’s
rings, etc) you’re casting and the type and quantity of metal you’re
casting. Also, as far as your flask temperature goes, you can play
around with whatever temperature works for you that is no higher than
Another note, the 7 minute working time of the investment using the
boric acid water is approximate given I’m talking about room
temperature in Hawaii. If you’re working in a colder temperature, you
might have more time. If in a warmer temperature, you might have less
time. If you mix with your hand, which adds your body heat, you might
have a shorter working time. You’ll have to experiment. One thing’s
for sure, you want to have enough time to vacuum/vibrate before and
after you pour the plaster to dislodge bubbles. If your plaster is
getting thick before you even pour, don’t pour it. Dump it. It’s
obvious you have a much shorter working time than you estimated.
Start all over and mix a shorter time so you have enough working time
to do the necessary vaccuuming and vibrating. (If you were to pour
thickening plaster, you might not get rid of bubbles and end up with
lots of cleanup work. Worse yet, you may have might end up with
voids where the thick plaster couldn’t get to. Those areas will cast
out in metal which could be a disaster.
No matter what, you have to experiment and take educated risks to
find out what works for you, your equipment, your specific needs, etc.
Try small batches and really watch your burnout temperature and time
carefully. Test different casting temperatures. When you find
something that works, record it. Try to see if you can get the
results on a regular basis. If you can, then you might try doing a
bigger more risky flask. Bottom line: The time you save in diamond
setting can be lost by improper investing, improper burnout and
Nothing is guaranteed but good luck just the same.