How to cast copy a vacform canopy **Sorted thanks**

[TeeELL]

Hi everyone,
I have a KORA models CW-19R which is supplied with a vacform canopy. On the real thing, the canopy framework is quite fine but the supplied canopy has, understandably, thick framework. I am considering creating my own, plain canopy and using tape or decal paper to create the frames.

Here then, is my question:

How can I make a copy of the canopy? My thoughts are to fill the original with ‘something suitable’ that will a. harden and b. be sandable. The idea being that I end up with a cast from which I can remove the frame work leaving it smooth and then try my hand at moulding clear plastic over it (I have saved many, many suitable pieces).

Has anyone done this? What would be considered a suitable medium for making the master? Casting rubber would spring to mind but removing the ‘frame work’ would be difficult. Filling the canopy with thin layers of Araldite (epoxy) might work, but I would need some sort of release agent.
So friends, has anyone done this and can give me some steers?

Thanks in anticipation

[chrism]

Google it. As there are a number of online tutorials on u tube etc to watch. BM forum has a tutorial I know. As does finescale modeller there are loads how to out there

[fredk]

I use a modelling plaster called Keramin. Its a plaster with ceramic powder in it.

An example. I used it to fill these yellow and slightly brittle SC1 canopies


then vac moulded a new canopy over the plaster buck




For vac formed canopies use plastic which is PET. Others tend to yellow and even go brown under heat
Keramin can be sanded and frame lines replaced with Tamiya tape, which is then all varnished over with a few coats of Klear/Future/Astonish which then needs a few days to cure. The finish on your buck will be the finish on the inside of your canopy. ie, semi-matt buck = semi-matt canopy, glossy buck = glossy canopy

[TeeELL]

Thanks Fred.
Perfect, I’ve just ordered some.

[fredk]

I didn't have a photo of the Keramin plaster buck before but here it is


and a buck for another canopy


For this Gannet canopy; sometimes you can mould over the original canopy but on this one I reckoned it would not do so I pressed it into some polymer clay, baked that then made a plaster buck from that mould

[TeeELL]

I am most grateful Fred. The plaster is ordered, the plastic set aside. We shall see what happens.