Servo - October 2010

other and align it on the mold. Remember the position in your head (or mark it) and pull the fabric off the plate as it is time to add a release. A release agent will allow the molded part to come off the aluminum plate when the part is done curing. Choosing the right release is also key to how the molded part may perform.

Traditionally, wax is the cheapest and most readily available release agent, and it can work quite well if applied correctly. Just remember if you use this system to apply criss-cross, not “Karate Kid” circles, yet wax on and wax off with

PHOTO 2. A few of the safety and general supplies you will need.

that criss-cross pattern. Apply at least 3-4 coats for the first time using the aluminum and always make sure the mold surface is cleaned well beforehand with some Acetone. Dish soap is a nasty thing in the composite world as it will leave behind agents that could possibly corrupt your resin matrix.

Team Think Tank (TTT), on the other hand, uses polyvinyl alcohol (PVA) as their mold release of choice. There are a ton of releases out there, however PVA has stood out as the best. It can be applied through an air gun, or simply by paint brush. It will create a thin film that is water-soluble which means you hit it with water and it will dissolve. Unlike other releases that may stick to the part and make secondary processes a pain, you can take the part to the sink and rinse it all off. You would apply this release on the mold but leave at least a 2” border not covered in it if you go the vacuum bagging method used in this article.