For some time I have wanted to have the roundels in the console room have the same profile that they had on the show. The ones I have now are just flat pieces of lighting diffuser (normally used in suspended ceilings) which I stapled behind the wall panels.

The roundels used on the show were made with fibreglass resin and matting. Since I'm somewhat fibreglass-averse and since I don't fancy laying up 100 of these anyway, which I think would take a long time, I decided to investigate vacuum forming.

The hard thing about the roundels is that the profile is actually not very evident from photos. Fortunately, PurpleBlancmange from TARDIS Builder's Forum was able to provide a sketch of the cross-section. Here it is:

I scaled this to the correct size for printing to use as a template.

The first task with building a vacuum former is to make the mould. I did this in very much the same way that I made the dalek dome moulds.

The tray with wood disks to fill the flat area

The former was cut out with a scroll saw

Former mounted and ready for pouring

Here it is after pouring

And here it is lit from the side, so you can see the profile more clearly.

I spray painted the mould with primer to hold it together a bit better. (Message from the future: I probably needn't have done this, as it seems to be holding up, and the primer is coming off with the heat.)

As you can see, the mould is very rough, but vacuum forming is not as detailed as fibreglass moulding, so I'm hoping that this will be adequate...