FADING LIGHT

[richard]

Any ideas anyone ? how to speed up the process of fading a pale orange plastic lens through to clear - i.e. is it possible with UV or whatever ?

[richard]

Strange I had thought that al or someone else could provide a devilish clever method

[Rusty Chrome (Malcolm Parker)]

Hi Richard.

The problem with fading coloured plastic is that it's actually damaging the plastic. Sticking it under a UV light might speed up the degradation, but you're also likely to make the lens more brittle or possibly even cause it to crack.
You could experiment using RTV Silicone Rubber to make a two part mould from the original and then try casting a clear reproduction in Polyurethane Resin. It might sound unlikely, and I've never tried it myself, but lots of people in recent years have been using this method to duplicate car bodies and other small parts for slot cars and modern casting resins can get quite close to an injection moulded part in strength and finish.

[Big Al]

I have always fought to get the orange or red back. Unless the lens is coated with lacquer or painted it will be within the structure of the plastic and as suggested I think it is effectively aged plastic. Experience shows that is brittle. I have cleaned out lenses with Acetone but it is a nasty chemical and it will attack the plastic if left to soak. That was converting KR200 sidelights from navigation lights.

3D computer printing?

[richard]

Thanks both that's another project - just had a peek at ebay and all the materials are available - I think a visit to a good local model shop might be called for as well - great