Best low cost materials for a large brush on mold? (2-1B project)

[forttusken]

I am nearly ready to make molds of my 2-1B parts (Chest, Back, Pelvis and two leg parts). I have calculated that I need a bit under 2 quarts of silicone to make a mold that is 3/8" thick. I am looking for a low cost options that would work well. Maybe I don't need to go that thick since the detail is pretty minimal and the surfaces are relatively flat. The master is clay over foam. I would like to use a brush on mold stiffener to provide rigidity since this is very important for the parts to keep their shape and not move around too much.

The positive will be made of aluminum powder mixed resin with full fiberglass layer under. I will at most be making only a few copies if that so the mold doesn't need to be too strong.

I heard this place is where the Mythbusters shop:
http://www.artstuf.com/shop/

THis is my first casting project with these materials so any suggestions would be appreciated.

Thanks!

 

[stormtrooperguy]

Since you made a point to mention the sulpher, you probably already know this, but that can cause silicones to not set up properly.

If I remember correctly tin cure silicones are OK, but platinum cure won't work well. Check that yourself though as I'm going totally from memory, and I do sniff a lot of paint fumes

 

[forttusken]

Since you made a point to mention the sulpher, you probably already know this, but that can cause silicones to not set up properly.

If I remember correctly tin cure silicones are OK, but platinum cure won't work well. Check that yourself though as I'm going totally from memory, and I do sniff a lot of paint fumes

I just double checked and it isn't sulpher based after all. It si Van Aken modeling clay. I have 10 lbs so I will have to do a few parts, cast then sculpt the others likely since I have so much area to do.

 

[steveo]

Would love to see photos of your 2-1B sculpt.

 

[forttusken]

It looks like I am going to go with Urathane with a shell material for rigidity. Rest Assured I will get pictures up once I get going on the sculpting.

 

[steveo]

It looks like I am going to go with Urathane with a shell material for rigidity. Rest Assured I will get pictures up once I get going on the sculpting.

Oh, I thought you were finished with the sculpting and were just getting ready to mold it. Sorry.

 

[ThrowingChicken]

You could brush on a layer, and as it starts to set tack on some gauze and do another layer to soak through.