Making of the PB400 Combination Light Lenses

First the original form for the combination light lens was made by hand from a piece of plastic, with lots of sanding and polishing to high gloss. The lamp housings where made by 3D-printing, which would have been possible for the lens mold as well. Then a silicon mold was made, see the mold in the lower left in the picture. To make the production more economic the lens was duplicated 8 times. After that it was cut in half to be able to make the combination lights in red/amber and clear/amber, see upper lenses in the lower right picture. With the duplicated parts the final silicon mold for production was made. This enables to produce 9 combination light lenses in one step.

The clear resin was mixed with red or amber dye and de-gassed in a vacuum chamber. But nevertheless small air bubbles could not be totally avoided in the lenses. This specific resin had to be cured in the oven for 1 hour. The lenses turn out milky if the mixing ratio is not perfect, and we had to start over again. Best practice is to mix substantially more resin as needed, because the mixing ratio can be determined more exactly for larger batches.