A month or so back I was fortunate to obtain a wax injector amongst
a large collection of jewellery tools that I bought. Although I have
been casting for some time I have been doing one-off work directly
from fabricated waxes. I would now like to develop my skills in
rubber moulding so yesterday I bought a package of Castaldo
LiquaGlass room temperature moulding compound and a suitable moulding
frame.
I chose this material because it sets transparent and this should
make it easier to cut the pattern out of the mould. I mostly intend
to use patterns made of wax possibly incorporating natural materials
so the room temperature setting is also important to my way of
working. I would be very interested to hear of other people’s
experiences with this system and perhaps more broadly insights in to
rubber moulding, getting the pattern out of an intact mould and wax
injection.
The wax injector has a hand pump to pressurise the tank and a
digital temperature control. It appears to work just fine
I LOVE their Liqua Glass- Castaldo sent me some samples ( you can
always write and ask for some until you find the right one for you
from their line) and the liquaGlass was in the package. It captures
the most intricate details and makes cutting the mould a breeze as
you can see the model inside. I had a bit of a curve working in a
non-dehumidified environment given their instructions for using the
catalyst, as it required slightly more than the instructions
indicated- but if your studio is air conditioned or in a
not-very-humid locale it works perfectly according to their chart in
the instruction booklet. I use an ordinary 2 part mold frame
(aluminum) that i use for delft clay or sand casting as well as RTV
mold making.The liquaglass is a bit more costly than some other
castaldo products ( they have a silicone compound that is equally
good but takes more time as it is not transparent) but the time
saved in not only cutting but reusing a mould that doesn’t have to be
skewed/pulled in any way to remove the model is a great time
saver.The extra cost is worth the time saved and quality rendered.I
will never use rubber packed into a mold and vulcanized again!..rer
I tried some last summer, and took pictures, intending to write up a
review, but never got around to it.
The short answer is that it works great, but is a bit fussy about
mixture ratios, and is (according to the instructions) incredibly
fussy about moisture in the air while you’re mixing it. If it were
truly as fussy as the instructions make out, you’d have to mix it in
a nitrogen filled dry box, as the moisture from your breath would be
enough to foul it up. The good news is that I didn’t bother with
that level of moisture prevention, and it worked just fine. (Just
mixed it normally in the studio. No problems.) A good (and accurate)
gram scale is an absolute requirement. No “winging it” with this
stuff.
Being able to see your model is incredibly handy, and its tear
strength is pretty good for an RTV. The only tricky bit about
cutting it is that it’s so clear that it can be hard to be sure
you’ve cut everything near the model. It’s very hard to see leftover
little bits that aren’t quite cut yet. If Michael Knight (from
Castaldo) is reading this, I’d suggest adding a little bit of a blue
or orange tint to it, just so it’s easier to see. (I was doing an
antique piece, and trying not to mark it up with scalpel lines. Thus
the issue with pulling up short of the model, and then trimming very
carefully from there. That’s what was causing me to not cut all the
way through to the model on the last heavy pass.)
Thanks for the useful feedback both on the forum and personally. I
did one mould yesterday and cut it out today. It was rather cold in
the house yesterday (around 20C) and very low humidity (35%) I
weighed out the mixture to 0.1g, vacuumed the mixture before and
after pouring in the mould. Today it had set beautifully. I found the
cutting fairly easy. The compound had a pale green tint. In addition
the cut surface showed as frosty area so it was easy to see whether I
had reached the pattern. The pattern came out cleanly but broken
because it was fragile (wax and shell). I now have the wax injector
warming up (it seems to take ages to melt a pot of wax) so I will see
how the mould works this afternoon.
I’d be happy to send you (and anyone else out there) a free sample.
Just give me your shipping address and phone number. I won’t call,
honest. It’s just that UPS insists on it.
If you are interested in free samples of any of our other
products,just ask. You can see them all at: www.castaldo.com.