If you want good to perfect casts, you’ll need to invest a little into the proper equipment and materials. While it’s possible to get decent casts without one, a pressure pot and compressor are vital to getting the best results. You’ll need to use pressure for both making your molds and the casts.

I recommend using Smooth-on products. They have a large variety of resins and silicones. For making the molds, I’d suggest trying Mold Max 15T. It’s a translucent silicon so you can see the parts in the mold which helps when removing the original part after the mold cures. It also has enough flexibility to remove the original part or casts. It’s a 24 hr cure time but it’s durable and you can get up to 50 runs if you’re careful.

For hard resin casts, try smooth cast 327 (or 325, 326). You can either cast as is, in an almost clear, or add so strong tints for translucent or solid color pieces. It’s a 4 hr cure time and has enough working time to fill your molds and get it into the pressure pot. 325 and 326 have quicker cure times but also significantly less time to fill molds. Rushing is one thing you don’t want to have to deal with when molding or casting.

For flexible resin casts (webgear), try Task 14. It only comes in black but it’s strong and flexible for high durability. It’s a bit thicker than the 327 and you’ll need a gram scale for mixing. You also need to work fast but it’s the most reliable flexible resin I’ve used. If you need to have a flexible cast in a particular color, Specialty Resin sells Flexit 90 that can be used with tints but know that you have to work really fast because of the short pot life/working time.

For making envelope molds, I always used plastic containers. Most office supply and craft stores sell ones that work perfectly for any sized parts. Making mold boxes out of foam board or lego takes too much time and involve extra costs instead of a container that’s ready to go and can be used over and over. I used clay strips and toothpicks/gorilla glue to place the parts in the container.

If you want good to perfect casts, you’ll need to invest a little into the proper equipment and materials. While it’s possible to get decent casts without one, a pressure pot and compressor are vital to getting the best results. You’ll need to use pressure for both making your molds and the casts.

I recommend using Smooth-on products. They have a large variety of resins and silicones. For making the molds, I’d suggest trying Mold Max 15T. It’s a translucent silicon so you can see the parts in the mold which helps when removing the original part after the mold cures. It also has enough flexibility to remove the original part or casts. It’s a 24 hr cure time but it’s durable and you can get up to 50 runs if you’re careful.

For hard resin casts, try smooth cast 327 (or 325, 326). You can either cast as is, in an almost clear, or add so strong tints for translucent or solid color pieces. It’s a 4 hr cure time and has enough working time to fill your molds and get it into the pressure pot. 325 and 326 have quicker cure times but also significantly less time to fill molds. Rushing is one thing you don’t want to have to deal with when molding or casting.

For flexible resin casts (webgear), try Task 14. It only comes in black but it’s strong and flexible for high durability. It’s a bit thicker than the 327 and you’ll need a gram scale for mixing. You also need to work fast but it’s the most reliable flexible resin I’ve used. If you need to have a flexible cast in a particular color, Specialty Resin sells Flexit 90 that can be used with tints but know that you have to work really fast because of the short pot life/working time.

For making envelope molds, I always used plastic containers. Most office supply and craft stores sell ones that work perfectly for any sized parts. Making mold boxes out of foam board or lego takes too much time and involve extra costs instead of a container that’s ready to go and can be used over and over. I used clay strips and toothpicks/gorilla glue to place the parts in the container.