Thursday, October 2, 2008

Resin Casting

I received an inquiry a while ago as to how I do my resin castings. It took me a while to get around to it, but I finally did, and here it is. Or at least the first part. this part will show you how to make a vulcanized rubber mold.

Step one is to make or find a suitable ship. First it heeds to have a flat under side. and second it you made it out of wood such as this one its best to spray it with a thick coat of clear lacquer of finishing spray to seal the surface so nothing will soak in and it will slide out of the mold more easily. On another note it fills the uneven splinters and wood grain on wooden ships such as this one.
Step two is to glew the ship to a piece of paper (hints the flat under side) this keeps the ship from floating to the top of the rubber solution.

Step three build a barrier around the ship to create the edges of the mold. legos work well as seen above.

Step four mix the rubber and catalyst then slowly pour over the model. Make sure you fill the rubber a few millimeters above the highest part of the model. Let sit for about five hours to harden completely.

Step five after waiting a few hours test to see if it is hardened. It should be solid and dry but somewhat flexible. If so remove the legos or other casing.

Step six tear off the paper and test under side for hardness.

Step seven carefully remove model from mold by flexing the mold until model pops out. The first time is often tricky, and if the rubber tears slightly that is fine, but be careful. Now you have a mold that should be good for about 100 castings. In time it will wear and likely break so hang onto the master if you are planning on making a lots. Good luck and God speed.


Eli Arndt said...

Thank you!

No worries on the long wait. It was worth it. I am new to casting and am hoping to do some for my Anatoray-inspired nefs. I think I might have to go with a two piece mold, but the same basics still apply.

Thanks again,


Eli Arndt said...

BTW - What material are you using for the mold making?

Smith said...

The material I use is alumilite RVT silicone mold-making rubber there two parts a base and catlyist. They also sell sets that include all the mold making components and the resin as well as some other useful bits. These materials can be found in most hobby shops.