Dear Everybody, My name is Lek. I’m interested to cast diamond wax
setting. I tried cast it for 2 times but it’s not success. My
diamonds on the ring are changed to be clouded. Please help me. I
would like to know the method starting from the investing, burn out
cycle, flask temperature, casting temperature, ect. I will be very
pleased to give your advice.
Thank so much
Lek T.
I'm interested to cast diamond wax setting. I tried cast it for 2 times but it's not success. My diamonds on the ring are changed to be clouded
Hi Lek, You might try the following. It’s worked for me as far as
waxing in melee under 10 points.
Get a plastic gallon jar. Fill it with 3000ml of hot tap water.
Weigh out 120 grams of boric acid powder and dissolve it in the water.
Let water stand until it reaches room temperature. Use this water to
mix up your investment. AN IMPORTANT NOTE: The boric acid affects
the working time. Instead of about 9 to 9.5 minutes of working time,
figure on about 7 minutes. The plaster sets up significantly faster.
Also, make sure your designs allow plaster contact to crown and culet
of diamonds so they will be held in place during burnout. You might
also sweep out the floor of your burnout oven and even consider
putting a clean kiln shelf down. This way, if some of your stones
float with the wax, you’ll be able to find them more easily.
During the burnout, don’t exceed 1100 degrees Fahrenheit. Hold this
temperature for a good long soak. I hold it about 4 to 5 hours.
Then adjust to your casting temperature, hold that for an hour and
then cast. Do not quench a hot flask. Let cool to a point where
temperature shocking the diamonds won’t be an issue. This makes
breaking out a lot tougher, but that’s the breaks. You may want to
collect your plaster in a tub so you can sift it later if you find
that you’ve lost stones.
Wax setting makes flush setting round melee in inexpensive items a no
brainer. Just drill a slightly smaller hole. Get hart bur just small
enough to fit in the hole. Position it at the right height and then
twirl a girdle groove. Set the diamonds by positioning them on the
lip of the hole. Then use a smoothed cup bur or beading tool and
gently push straight down to seat the girdle. Make sure your table is
level. After casting, you can take a polished burnisher made from an
old beading tool and burnish a shiny ring around the girdle.
Good luck,
Donna Shimazu
Dear Donna Shimazu,
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.
Nice to see you, you teach me a lot of technique!
Sincerely,
Lek T.
Thailand
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
the 1100F.
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
improper casting.
Nothing is guaranteed but good luck just the same.
Donna
Dear Donna, Thanks once again for your advice. I’ve already cast my
10k white gold ring, the result is good. My last 2 time, I cast above
1100 f and my diamond turns to be cloud. Now, I know a lot of
technique from you, I will try and observe the result every time of
my casting.
I live in Bangkok, Thailand. The weather here is hot, may be I can
use the same working time like you.
Sincerely,
Lek T.