Thanks! I've ordered 2kgs from ea- they may not be the Rolls Royce of Silicon- but I'm pretty sure that I'm going to ruin the first couple of moulds anyway!
So what else do I need? Lego?
Cheers
Andy
In my experience the silicon rubber can still find it's way through Lego unless you seal it with modelling clay or similar.
A simple and relatively quick way is to use a clay (like 'Klean Klay') to build the walls themselves. Flatten out the clay with a rolling pin until ~5-8mm thick, cut strips to the desired height and wrap around to form the wall. If you need more than one strip, it's just clay, massage the two pieces together and sealing it is easy as you just press the edges with a suitable tool like those rubber 'paint shapers' to seal the gaps. When finished, mash it all back into a ball ready for next time. The same clay can also be used for the other half of a two part mould.
Cheers!
Joe Thomlinson