Casting plastic toys

Jewelry Discussion
1

I have another question; There is a plastic fork of a toy motorcycle
I would like to burn out and cast but Isuspect the chrome finish over
the plasticmight interfere with the quality of the silver or even
ruin the casting in the process, I have cast several micromachines
before which paint wasn’t removed for burn out and I have gotten
excellent results but chrome is a metal not paint and I don’t know
how to remove it and I don’town any plating equipment. Next question;
I have noticed that people who buys silver jewelry feels more
attracted to thebright silverfinish of some items that have been
electroplated which in many times preserve it from tarnish and
oxidationversus the plain natural silver tone thatshould be the most
appreciated and genuine . Anyway.what kind of plating it is. Is it
silver flash. bright silver, nickel plated or rhodium? Marco

2

I Might be wrong but I think if the fork of the toy motorcycle is
plastic it is paint or the plastic that has been injected as silver
colored plastic not chrome and if that is the case there is no
chrome in the paint. Casting temps should be hot enough to burn away
any type of paint or colored plastic that is used on a plastic toy.

Regards J Morley Coyote Ridge Studio

3 
   I Might be wrong but I think if the fork of the toy motorcycle
is plastic it is paint or the plastic that has been injected  as
silver colored plastic not chrome and if that is the case there is
no chrome in the paint. Casting temps should be hot enough to burn
away any type of paint or colored plastic that is used on a
plastic toy.

The “chrome” plastic parts aren’t usually painted. it’s a vapor
deposition layer, and often is metal of one sort or another. Whether
it’s actually chrome, or something else, I don’t know. But I DO
know, from experience, that it doesn’t burn out as cleanly as do the
plain plastic ones. And even they often tend to leave a bit of
residue or discoloration in the flask. Still, the castings one gets
usually are still quite acceptable, even so. At least, I’ve had
decent luck…

Peter

4

Here is a possibility for your casting delima. Since the piece is
already plated why not add more plating to compensate for mold and
wax shrinkage and then pop a rubber mold. I have seen this done on
jewelry and it does work. Frank Goss

5

I’d bet the silver colored plastic has pigments in it (probably
chromium)- and won’t burn out clean (it will leave ash). Why not take
an RTV (Room Temperature Vulcanizing) mold off the part and cast from
an injection from the mold?

HTH
Kate Wolf, Portland, Maine hosting workshops by the bay.
http://www.katewolfdesigns.com

6

i build superbike and GP models, and if i am going to replace the
fork tube, i put a rod in my flexshaft and spin it while i apply a
file, it works like a cheap little lathe, then sand and polish and
coat in clear lacqure (sp) and you have some really cool forks. PS I
race Bikes too.

Aaron A Tracy

7 
i build superbike and GP models, and if i am going to replace the
fork tube, i put a rod in my flexshaft and spin it while i apply a
file, it works like a cheap little lathe, then sand and polish and
coat in clear lacqure (sp) and you have some really cool forks. PS
I race Bikes too.

Hi Aaron Very interesting . I love bikes too. I have built and
modified some micro machines bikes. One is a Yamaha superbike and a
Suzuki. My dream is to cast the perfect Harley Davidson, I already
made a fat boy out of a micro machine the problem is that the parts
made of rubber don’t burn out good and I have to make it by hand.
Right now I’mtrying to design a custom drag bike with preexistent
micro machine parts. I’d love to see the ones you have made.

P.S I race bikes too. (in my imagination)
Marco