First step, cutting the paper patterns taken from the design drawings.

I wrapped the PAL in plastic and built a clay model around it.

The result after a couple of hours of modelling.

Next I made a wooden frame around the clay model.

And filled that up with casting plaster.

 The clay model did not come out in one piece after drying.
But that's no problem since I'll just be using the plaster negative.

I first tried some regular black silicone.

While this seperated quite easily from the mould, the end result is not quite good enough.

Next try: 2 part poly-urethane rubber.

First the mould has to be covered in vaseline.

Once mixed the rubber pours quite easily.

Working time is around 10 minutes.

To speed up the drying process, I put the mould in the oven at 60 degrees for a while.

That was not such a great idea. Apparently there was still some moisture in the mould
and the elevated temperature has caused it to react with the rubber.
Which has, very fittingly, turned into a semi-solid, bad smelling, sticky blob.

One more try with the poly-urethane, this time drying at room temperature.

That looks and feels much better!

Still a couple of small blemishes but otherwise pretty good.

And it does what is was supposed to do: stick like crazy.

Finally I used some car weather stripping rejuvinator and white acrylic for the finishing touch.

The end result.

After this making a red model was quite easy.

Apart from the glossiness, it's close to perfect.