making new molds

[g0rd0n_rc]

I'm looking into using old, yellowed vacuform canopies as the masters for making new molds.
Does anyone here have an idea if it's good to use Vac cast resin for the molds and if it comes in a package smaller than the 5.3kg I found?
I'm also concerned it's difficult to drill airholes in this material. My workaround is to use pins during the casting process to avoid drilling later on.
Is that a good idea?

 

[PourCraft]

Vacuform canopies work well as masters.The Vac Cast resin is strong, but 5.3kg is too much unless you're making a lot at once.Try to find smaller packs like Smooth-Cast or see what local shops have.Your idea of using pins instead of drilling air holes is really smart. It's much simpler than drilling after curing, especially with tougher resins.I've done that with a few small canopy molds and it turned out great

 

[Briddle Tee]

Using vacuform canopies as masters should work fine. Vac cast resin is great, and yes some suppliers offer smaller kits, your pin workaround sounds smart for avoiding drilling airholes later

 

[zippy]

I guess you could try a softer casting resin or even RTV silicone if detail and easier drilling are your priorities. Using pins is a clever workaround, but should also consider making a 2-part mold with built-in vents to avoid postcasting mods altogether. Smaller kits are often sold by specialty hobby shops online

 

[Re5inJunki3]

worked on a similar project a few years back with some experienced canopy masters. Using Vac Cast works well, but drilling later can be a real challenge. That pin approach you mentioned made things a lot easier for me than drilling. I also discovered some smaller 1kg resin kits from local hobby shops at that time, so it might be worth checking out

 

[NoSnow34]

Vacuform canopies work well as masters.The Vac Cast resin is strong, but 5.3kg is too much unless you're making a lot at once.Try to find smaller packs like Smooth-Cast or see what local shops have.Your idea of using pins instead of drilling air holes is really smart. It's much simpler than drilling after curing, especially with tougher resins.I've done that with a few small canopy molds and it turned out great

Thanks for the tips! I'm just getting into this and had no idea vacuform canopies could be used as masters. Do you heat them before molding, or use them as-is? Also, when using pins for air vents, do you place them before pouring the resin, or after the mold sets?