I have molded lots of parts for things that i use a lot and the rare parts that are hard to find so i have them again and of course the one that i make and like i mold them to reproduce. anyway, got an idea for a cockpit to light up. The question is. Can you mold a resin? would the heat melt the mold, thinking it would and if i use the type that you pour out of the bottle would it be hard enough? not sure if anyone has tried this or not and before i go trying this wanted to know if anyone has? just need to do the instrument panels. maybe it is a little much.......

Yes, you can get clear, two-part resin for making copies of parts. If you just need a small amount, you can also use clear, two-part Five Minute Epoxy that can be bought at just about any hardware/ do it yourself / Wal-Mart store. It comes in a double syringe applicator.

Smooth On offers some nice clear resins. pressure casting or vaccum casting would be the best ways to go!!

Hmmmm... might have to try the opoxy. think i got some around here some where. if not it is not that expensive. have to give it a try and let you guys know. got to get some more RTV first.......

Tom, you will need to bake the RTV mold in a low ( 180 deg ) oven for 1/2 to 1 hour before you try casting clear.
RTV gives off an alcohol which will inhibit the cure of clear urethane.
The epoxy will not like the alcohol either.

Thanks Edward, might have to look at the smooth on clear resin. I will check it out and see.

You're also going to need some way to de-gas the resin before you pour it in to the mold.

Or, you could send your parts my way and I could cast some copies for you...it's what I do

Edward, De-Gas? meaning what? I did find some water product for model rail roads do not rememeber the name of it but, i did see and example of it and it look nice and was very hard and clear. it is two part mix and all they had was the two 1 Gal bottles for about $100. was looking for a little bit less to try. got a dio i am working on and would like to see if it is any good before i drip a $100 bucks into it and then not like it.

Tom, typically, when casting clear resins ( urethane ) the caster will mix the 2 sides ( A & B ) then place the mixing container in to a vacume chamber. Then, in order to remove the excess air in the mix, a very high vacume is pulled and the resin will expand due to the reduced atmospheric pressure. When it expands, the air bubbles will expand as well....this forces them to pop...thereby removing most of the air in the mixed resin.
Without this step, it's very difficult ( not impossable ) to get bubble free castings.

I'm not certain what the material is which you found at your hobby shop.... it could be either Epoxy or urethane. It should say on the container.
I might recommend that you go to smooth-on.com and check out their "crystal clear" resin. What you need ( if you don't have a de-gassing chamber ) is one of their slow cure versions...not sure which would work best...call their tech line and ask a few questions...they're really helpful.

If you dont mind my asking...how big of a job are you trying to pull off?
If it's something small, I might be able to help you out...I'm fully set up to do pressure casting of resins.

Ed, sorry been TDY for a couple days. I want to start an F-18 and want to fully light the thing. to include the cockpit. so i figured if i could light all the panel lights and screens it would add to the effect. so besides the landing lights, marker lights and possibly the engines i think if i could lights up the cockpit it would just complete it. so i figured if i could cast the cockpit in a clear and paint all the screens, buttons and switches ect the colors that they should be it would be neat. and give off a great effect. i have not started the kit because i am trying to finish up some other kits that i started before leaving for Iraq and Afghanistan so they have been sitting for two years. and i entered a couple of the campains so got to finish those as well. which some fit the campains. then i want to start on the F-18. thought about if i could get this clear casting down maybe some dash boards in vehicles as well. but of course when we run missions at night we do not use lights at all so there is nothing to light up. anyway it is just an idea that i would like to try. and thanks for all the good ideas and the advice...

Just as an aside, the heat involved will not affect most RTV rubber. Most are capable of handling white metal.
As for your idea of doing the intrument panel alone you shouldn't have to be too concerned with de-gassing. It's a good idea, and probably far easier than using fiber optics. I've cast clear cupolas before, (much like AFV Club now does with their Centurion series) using molds made from the originals, to get the clear vision block effect, and bubbles were almost nonexistent, especially since so little of the part remains unpainted.