Was wondering if anyone could recommend an injection wax that gives
extemely fine detail on a rather thick piece. Have a project for a
medallion approx. 1 1/2" round and 1/8" thick with a company logo cut
in. Got the piece laser engraved into acrylic and have made an RTV
mold from this original which has all the detail but the waxes I’ve
tried won’t fill the detail. Have tried more pressure, less pressure,
more heat, less heat, more vents, less vents and any combination I can
think of. The two waxes I’ve tried are Rio’s Buckle Wax and Kerr’s NYC
Pink. >From looking through all the catalogues I have on hand - Rio,
Gesswein and Grobet - all the descriptions of the various waxes seem
to indicate all the waxes are wonderful on all projects. Any
suggestions Please.
Lorne, It sounds like you need to use some mold powder (Baby Powder
without corn starch) in your vents. This will help the air to vent.
There is a good article at the Precious Metals West Web site http://www.preciousmetalswest.com/ in Articles-Mark. Timothy A. Hansen
TAH Handcrafted Jewelry
P.M.B. 131, 305 N. Second Ave.
Upland, California 91786-6028
U.S.A.
Lorne, I have tried a wide variety and today use Kerr Tuffy Green and
love the detail. There are several things to consider; detail in the
original mold, temperature and injection pressure into that mold.
Even though there are some basic guide lines and numbers to start out
with, there is nothing firm…you really have to discover the proper
mold material, temperature and pressure for your specific equipment.
Here’s to good casting… Ron Stephens
Dear Lorne, The best wax I can recommend is the Plast-o-wax sold by
most major suppliers. I have done a lot of this type work and to tell
you the truth, any wax will work with the proper injector Now here’s
the catch. To get the detail you are looking for you need the
properties of a plastic injector. And wax doesn’t work too well in a
plastic injector.
The key I found to getting that fine a detail is to use a metal mold
and use a paste wax injector. Here’s another problem. Paste wax
injectors cost either $2,700.00 or if you want the best $12,500.00.
The one affordable thing you could try is to get one of those old
hand pressure wax injector. Those are the kind with the piston for
pressure hand operated. The nozzle for the mold is facing the same
direction, up. You pull the pump handle up, firmly put your mold on
the nozzle and press down. Clamp your mold with a C clamp so wax
won’t leak out. Now press down hard. Be careful not to squirt wax up
to the ceiling. This will deliver the highest pressure and greatest
detail. Most waxes will work with this injector although I would keep
to a thinner property in the wax.
Hi Lorne, Depending on the level of detail and letter depth, you may
not be able to get the detail you are looking for out of a rubber
mold no matter what wax you use unless you use a vacuum wax injector
which very few people have . Normally, Items as you have described
with wording on them would be done in a pantographed metal mold. What
I would suggest to try with your rubber mold is to use Arrow Root
powder Available in the spice section of your local supermarket…
pour some into a small canvas type bag (or whatever is available) to
use as a powder bag. Then, Powder the interior of the mold , lightly
blow off excess powder using lung power … close the mold and inject
the mold …make sure to hold the mold against the wax pot nozzle for
about 8- 10 seconds… this will keep the wax pressurized while the
wax cools and help to eliminate some problems.Do not allow any wax to
flash or leak out around the nozle area (loss of pressure in the
mold) Doing it this way may get you the results you need, but remember
that you need to let the mold cool between injections for quite a
while or your results will become worse with each subsequent
injection. You can use other types of powder other than Arrow root,
such as talc, but My preference is Arrow root. Give it a try …
Daniel Grandi http://www.racecarjewelry.com
One, is the detail you are after in the RTV mold?? Really check this
out first if you havn’t already done so. It is a silicon RTV or some
other material? What? Using a release dust and if so what and how
are you applying it?
What pressure are you using? How hot is your wax? Is your
thermometer correct? How long are you holding the mold on the button
under pressure?
We use Serria Red. Very good detail, hard (for me easeir to make
fixes and keep clean, sharp edges) and pretty low shrink on thick
pieces. If really thick or heavy pieces, hold on the injector button
for a while.
John Dach
MidLife Crisis Enterprises
C.T. Designs
Cynthias sculptures are at: http://www.mlce.net
Maiden Metals,
A small bronze foundry, no web site yet!!
“Wonder rather than doubt is the root of knowledge.”
- Abraham Joshua Heschel
Hi Lorne, Please try Castaldo’s green “buckle” wax. You will need to
inject for a longer period than usual. Also, here’s a tip…get a
large safety pin and stretch it open. Gently tap the point on some
steel. You want just a slight snag when you drag it along your
fingernail. Check out your failed injections for the spots that won’t
fill. Push the pin in your mold in the corresponding place through to
the back side of the mold. Leave the pin sticking there for a minute
while you use your scalpel to cut a 1mm deep slit from the pin to the
outside of the mold. Then flex the back of the mold and powder the
slit. Repeat wherever you can’t get correct fill. This is called
pin-venting. This is the least intrusive way to expel unwanted air
without slashing your molds to bits. John, J.A.Henkel Co.,Inc.,
Moldmaking, Casting, Finishing
Hi Lorne, I recently had the same challenge injecting a detailed mold
made from a cad/cam model. I tried all the same things you mentioned
and then had it suggested by a friend to turn my pressure down a bit
and hold the mold on the nozzle longer. Amazing, a full 15 count with
the pressure at a bit under 5 and the temp at about 155 gave me a
great wax that needed no touch up. I also kept the mold dusted and
free of extra wax in the vents. It also seemed to help to not squeeze
the plates on either side of the mold, too tight. Right now I squirt
with this flexible wax-bright pink, from Rio. Kerr I think. Good
luck!
I would like to appeal to the collective wisdom and experience of the
group for help… I make molds of many of my company’s original
pieces, then later shoot waxes and modify them for other pieces. I
am looking for a wax that is good for carving and injection, which
won’t gum up my files and tools, won’t collect dirt like a magnet,
and won’t shrink overly. So what are your favorites?
Allen, Over the years I have used nearly every injection wax
formulated searching for the best results. The best carvable injection
wax in my opinion is made by Conley Casting Supply. It’s called Alpha
Orange. Let it cool and harden for a while for best results. Every wax
has its trade off. The constituate that makes it carvable (carnuba
wax) also acts like colesterol in the injectors plumbing after a few
months. If this is a problem for any wax or wax pot you can dismantle
the nozzle parts and put them in a small jar of citra-solve and
suspend it in the ultrasonic. Oh yeah, you can call Conley at
401-785-9500. John, J.A.Henkel Co.,Inc. Moldmaking Casting Finishing
Hi Allan, So far, my favorite injection wax for rework is Conley
Orange Injection Wax. This is a good injection wax for reworking
and for building up relief. It can be filed and scraped. It will
eventually gum up the file, but not as quickly as other injection
waxes I’ve used. Like most injection waxes, it becomes brittle with
time. Melting temperature approximately 150=B0 . On hot days (I
don’t think I’ll be seeing one for quite some time…) I put a few
injected waxes to be worked on in a small steel bowl, then I put this
steel bowl on top of a larger bowl of ice. If the wax I’m working on
gets warm and gummy I put it in the bowl and pick up another wax to
work on.
Conley Casting Supply (orange injection wax) (401)785-9500; 124
Maple St., Warwick, RI 02888 ( I am not affiliated with this
company, I just like their product…)
HTH,
Kate Wolf, in brisk and breezy Portland, Maine
Hey all, I have had the best results with Rio Grande’s Blue Carvable
Injection Wax for rework. It’s much better than the Conley orange
stuff, and doesn’t gunk up your injector’s plumbing. Rio’s item # is
700-245.
Several modelmakers I have worked with also like blue Plast-O-Wax a
lot.