OK, I'm really new to molding and plaster of paris, but I'm looking at making a mold for plaster of paris so that I can make multiple plaster of paris groundworks from it.

Can anyone point me in the right direction for the right "mold" materials and perhaps even a technique. Do I start with a plastic/rubber mold? Can I make a plaster mold to actually mold more plaster in it or will they stick to each other?

Any advice or even point me to a good website would be great. Thanks.

I hope you get some good responses, as I am interested in them too! After seeing some of the fantastic molding/casting and dioramas I went out and spent about $75 so far and have only made piles of goo! Though I have made some nice originals…..

Tons of ideas
Blister Packs
Legos
Kitchen foil
Silicon

Here are some features
Blister
Kitchen foil
Wall Building

Here a short article I wrote some time ago. Might give you some ideas
Casting a 3D wall

Hey,

Funny you should mention this because I've been doing far too much of it lately. I'm not sure what you are building, but you might want to use hydrocal instead of plaster of paris. All it is is a fortified plaster. It is a lot stronger and the demold time is significantly less. It's still cheap (though, not as cheap as normal plaster) and is readily available.

I just make my molds from basswood or balsa and sheet plastic. If I'm worried about the plaster sticking, which it usually doesn't, I'll coat it in silicaon mold release, PVA or Vasoline. If you want some type of pattern, you can roll out clay like you would when making a pie crust, cut it to fit your mold and stamp a pattern.

Just make sure you are in some place where you don't mind a lot of dust. The whole process is a ton of fun and really is a nice break from plastic. Here's a link to what I am working on now. You can see some of the techniques I was talking about: St. Goar Structures

I am working my way through a lot of this two right now, trying to figure out what works best and what doesn't and would be glad to pass on any tips along the way.

~ Garth

I experimented with plaster molds using sheet plastic. I made some molds of modern concrete jersey barriers. They came out very good, and what I like about plaster is no two barriers come out exactly the same. They all have differant texture characteristics like in real life. The only thing I dont like about it is that I have to break the plastic mold to de-mold the barrier. I have to come up with a better way to make a more sturdy and easily dissassembled mold for this.

I've made several castings using the methods above. Over time I've found that making the basic shape and then carving it into the final piece is easier and allows for more variety in your diorama. You can make up some squares and rectangles that you can use several times from plastic and small segments of wood. Using LEGO or similar to create voids for windows and doors is also a good trick, and gives you a plumb and true door/window frame.