Mold and Flange Construction

[variverrunner]

Sneakyb

In planning your mold you might consider setting it up so that you could use Smooth-0n's brush-on silicone bagging material. Check out their website. The result is a highly reuseable vac bag that does not require perimeter tape. Their detail is to terminate the bag edge into a dovetailed routed slot in mold edge.

I am in the process of adding thicker flanges to one of my molds to have enough thickness to route. I'll be smiling if I don t need to chase leaks at the ends and perimeters of my vac bags.

Good luck with your project

Allan

[Herman]

I would be interested in your experiences with this material. Till so far some of my customers have used reusable silicone bags, but the experience was that the lifespan of the bag, including the labour to make one, does not come in favour to applying a vacuum bag with sealant tape.

Perhaps this is different with awkward shapes.

For polyester products: Make sure you clean your silicone after each demoulding. Styrene crystals may form, making the bag brittle.

For epoxy products: I have managed twice to get a part stuck to a silicone mould. Even using mould release did not prevent that.

For this moment I do not feel that a silicone bag can benefit from the gap between semi-rigid top moulds (RTM Light) and vacuum film. But I believe that in certain areas it can be used economically.