Replica Knobs for 1948 Motorolla Goldenview TV

By shear chance, I obtained three almost identical Motorolla "Goldenview" televisions with 7-inch picture tubes from 1948. One had its knobs, the other two did not. Replica knobs are available for purchase, but they are resin-casted. That would be fine, except that the knobs include gold-colored, painted, concentric circles. On the original knobs, and hence on the casted replicas, the circles are raised ridges, and not grooves. That makes them almost impossible to paint by hand! I tried casting a replica of one of my original knobs, and the hand-painting did not turn out well at all.

So instead, I rendered the knobs in 3D, and printed them on my Halot 1 resin printer. This gave me the freedom to include circular grooves instead of ridges, which are much easier to paint, and look just like the originals. The only hard part was to find a way to resin print very dark brown plastic. Since resin printing depends on UV light being able to penetrate into the resin, there are very