How to make a solid shell replica from a flexible lexan part?

[emperor]

as above.

I have a rc body shell used in rc cars and the material is supposed to be light and flexible (lexan material as shown below) but I prefer it to have a rigid shell instead. is it possible to somehow use it as a mould and coat the inside with some sort of resin/plastic ? maybe cut outs for the windows ?

 

[IEDBOUNTYHUNTER]

Yes you can. Lexans not great for that but you can do it. Scratch the inner surface up real good to give the resin something to bite into. Then coat the inside with resin. In smalls amounts let dry. Repeat sanding then do another layer. If you try to do it in one big pour the resin will generate to much heat and melt the lexan. What i would still do is place the lexan on a wet towel and do the layering on the wet towel to help keep the heat down

 

[MonsieurTox]

I think he was wanting to know if it could be use as a mold.

I think yes, it can be done, since it was vacformed over a male plug (most of the time the case with RC body cars), there's no undercuts. Just put a thin coat of release agent (wax etc), and you cant put your gelcoat with a brush then you resin and FG (if you go this way), just do a test on a small lexan piece to see if there any bad reaction between the lexan and the gelcoat and or the resin.


But I honestly dont think there would be a bad chemical reaction and you'd be able to use cut and use the lexan glasses to put inside your FG shell.

 

[rbeach84]

Looks to be a female molded part, given the details that are on the outer surface. If the goal is to have something more rigid, using the original and reinforcing with an internal frame or using RFG inside should stiffen it up. You could also make a 'float box' for the interior (a simplified shape that provides a space between it and the exterior) and reinforce it with an expanding urethane foam. Probably best to do that with the shell braced in some way to prevent the expansion from distorting it (leaving the space open helps.) Once it is foam reinforced, you can carve it as needed.

Regards, Robert

 

[emperor]

Looks to be a female molded part, given the details that are on the outer surface. If the goal is to have something more rigid, using the original and reinforcing with an internal frame or using RFG inside should stiffen it up. You could also make a 'float box' for the interior (a simplified shape that provides a space between it and the exterior) and reinforce it with an expanding urethane foam. Probably best to do that with the shell braced in some way to prevent the expansion from distorting it (leaving the space open helps.) Once it is foam reinforced, you can carve it as needed.

Regards, Robert

the lexan body is supposed to be mounted on a rc chassis so I cannot have it filled up or something.

 

[rbeach84]

Emp, I understand that; my reference to a 'floating box' is so you can create a cavity to accommodate the RC car chassis. Just consider you could make a 'custom fitted' foam spacer/support that fits over the chassis and inside the shell. To make the floating box form, you can use any sheet material such as cardboard to create an inner shell form fitted to the chassis;, then seal, coat with a mold release agent and then center within the shell and fill the gap with the foam.
R/ Robert