"Resin mold for latex casting?" Topic

So I have a little bit of experience in casting resin in RTV molds. Our club needs more roads for 28mm Bolt Action and so far I have been making dirt roads by using acrylic caulking onto felt pieces and then texturing and cutting and paint and whatnot but the cold weather has put that one hold. I've been think about how to A: Speed up the process and B: how to make cobblestone roads. I've been brainstorming making a master of the cobblestone roads (probably with pink foam) and then making a resin mold I can then put the caulk into, put the felt backing on and then pull out when it cures in a couple hours. How feasible is this? realistically we need enough roads for 5-6 tables and this seems much cheaper than buying a commercially made product. I'm certain I can handle the mechanics of the process and have access to a pressure pot and air compressor to make the resin molds. Is there a better way? Am I over thinking this?

You can get paper, cobblestone roads at the local railroad hobby store, in HO scale.

I suspect they're available in other scales too.

Not sure resin will work with the foam. Probably will get too hot and melt it.

Silicone rubber to make the mold should work though.

I didn't think about the heat melting the foam. I'm not sure that silicone will work for the mold since I will be using caulking for the material and (I assume) will have to push it into the mold to make sure it gets into the recesses.

I know I can get paper stuff either from the various papercraft websites or from model train stores. But my experience with papercraft is it moves too easily on accident and gets destroyed too quickly. I'd rather have latex or acrylic roads that are more likely to hold up to the wear and tear of the club using them and will stay in place most of the time.

You could try plaster instead of resin. It still gets quite hot when setting but shouldn't damage the foam too much. Cheaper too.

Plaster should make a nice cheap mould for latex.
Of course there are some issues with latex you might want to consider first before you proceed.
1. Some people are allergic to latex and in extreme cases could go into anaphylactic shock. I work in public health in Australia and latex is a band product for that reason.
2.the latex will eventually dry out and crumble over time. Ever found an old rubber band in a draw?
3.Latex is a to get paint to stay on. You more or less have to use a latex based paint, which only seems to come in garish glossy colours.

I bought some commercial latex terrain for my games club back in the 1990's. I hated the stuff in the end. it was the most frustrating item I had ever come across for wargaming. It ended up being tossed into a box of terrain that didn't get used much. About 5 years later we were having a spring clean and a fellow member showed me the piece wondering what it's origin was. The piece had gone all crumbly like rubber pastry around the edges, even the bits that were cacked in paint, glue and flock.

Sorry this doesn't help you much with your request for advice, but it might save you from some future grief.

As an alternative, I would look for paper cobblestones, try an art supply that sells embossed or specialty paper for scrapbooking.

Also try cobblestone plastic sheet, I bought a stack of this 2 years ago made by an english manufacturer called Slaters. and A4ish sized sheet is about 2-3 GBP in cost.
Ewan

I'm going to be using acrylic caulking for the roads actually. Cheap, easy to clean up and takes paint without primer. As far as latex allergies go, if someone is allergic to latex then they should know enough to either ask or not to eat the roads. I'm not going to let an rare condition dictate how I play a game, similarly I eat peanut butter and jelly sandwiches in public regardless of who has peanut allergies. I'm not a fan of papercraft terrain for many reasons and if the roads last 5 years I'll actually be happy to make some more.

Owww Kayyy

Did you try this ?

I was thinking of doing the same thing and wondering what would make a good release agent. The acrylic caulking I used for a terrain mat was very sticky (that's another story :) )

I was thinking just about anything would do for the mold as the latex should peel away when dry (if the release agent works. Was going to try it with air-dry clay as the mold

Thanks

John