I found a way to make old Yellowed Plastics ,Ramps etc Clear again.
Maybe posted here before but not sure I haven't searched.
You have all been there. You have Yellowed plastic and all the cleaners on Earth do nothing but clean off dirt and old Nicotine but they are still yellowed. Thats because its a chemical change from the Fire retardant used in plastics in combo with UV light.
The Solution? A Peroxide Sunbath.
Place your piece in a Clear container and fill with Peroxide to cover item then cover seal with seran wrap and leave in the Sunlight or a UV lamp for a few days and thats it.
Don't believe it below are pics after the bath.
Both pieces are from A STTNG that I am restoring for a client I used the one on the right to test the theory and you can see the results. I left it in the sun last weekend before I left my house and upon returning this weekend this is what I was greeted with. A perfectly clear piece.
Original pieces as removed from machine.
Peroxide bath in ziplock bag
Results on right.
Decals removed after bath results on left.
Restored and redecaled and painted Shuttle