I just read a good tip over at Cardmodels.net on how to make canopies from plastic PET bottles (soft drinks, etc.). The advantage seems to be that the PET plastic will shrink around the mould when heated, thus eliminating the need for complex vacuforming.
The instructions can be downloaded from below [original source: Cardmodels.net, now extint]. The inventor is the user name "Hpept" from Brazil. Here's how it goes (reading this will save you downloading, unless you want to save it):
1. Glue up the canopy from the paper parts supplied in the kit, but keep tabs on the outside (the inside will be the shape of the mould).
2. Fill the mould with two-compononent epoxy, any kind. (I'm thinking that gypsum [plaster] would do just as well if you, like me, wish to stay away from allergenic substances).
3. When hardened, tear away paper and sand (if necessary) the mould with very fine sandpaper (600 grade should do it).
4. Choose your PET bottle according to the hue desired (most likely a slightly blue tinge, which is nice). Cut away the bottom and mount the mould against an inside part of the bottle which conforms best to the mould. Use small scrap pieces of wood or similar to make a tight fit.
5. Heat up the PET bottle above your cooking plate at a distance of about 30 cm. Use some tool to hold it, since the bottle will get very hot. The PET bottle will now shrink nicely around the mould.
6. Cut out the canopy, trim it, and glue on paper framework parts. Mount on the model with suitable glue (PET plastic will take cyanoacrylate, which is a GREAT advantage, but I'm thinking that more ordinary glues will do the job as well).
We should all be grateful to "Hpept" and Cardmodels.net for this nice tip. The photos below are abstracted from the instructions. They show:
1) The mould after sandpapering, ready to cast a new canopy
2) Canopy just cut out and framework glued on it
3) Canopy ready to be installed on the model
Leif
