Cheap Mother mold material - Plasti-paste alternative?

[ArtFx9]

Hello, I would like to know if anyone has some experience with using cheaper materials for mother mold making where fiberglass and epoxy/poliester resin is not the best solution - complex and small shape, antlers for instance. I was thinking of maybe mixing saw dust and poliester resin and applying it as a paste. What are your thoughts on this?

 

[nick daring]

I know plaster and other gypsum cements can be used.

 

[animefan]

you can buy fibers to mix in polyester resin, there cheap and will the trick. Any place that has fiberglass supplies would have them.

 

[MadMike]

when following the contures of your mold, I would use plaster bandages, they are strong, fast-setting and don't cost the world.

When having larger molds with a complex form, you could also try to make a frame around it (using cardboard for example) with space between the mold and the frame (just like when making a blockmold), and then you fill the cavity with expanding foam. a bit tricky because you then have to cut it open carefully around the silicone mold, but you'll get a mothermold that's cheap and lightweight

 

[loly2kn2]

You will need to add some kind of reinforcement to it. The polyester wouldn't be strong enough on its own.

Chopped strands should do it. Catalyse the resin first, then just keep adding them until you get the thickness you like. Then splodge it on.

 

[bookface]

What others have said...substitute the sawdust that you thought of for chopped strands of fibreglass, and you're good to go. MB Fibreglass sells them in a few different lengths, from 3mm to 13mm.