Update on PDP-8 Switches
Over the past few weeks I have been working on-and-off at producing the switches required to replace the ones broken on the PDP-8 at Carleton. And they're done.

Of the 26 toggle switches on the panel, only three were still intact. Ten needed new hinge rods, which I produced out of stainless steel. A total of 13 needed to be replaced altogether, eight brown and five gray. I made a two-part mold using Alumilite's rubber, and then cast the switches using their quick-set resin. There were a few bubbles, but only the visible ones were filled. The 1/16" stainless steel rods used for the hinge pins, 12mm long, were cast right into the resin.

This weekend was spent finishing them off. I primed with Krylon. For the brown switches, I found that Testor's "1166 Flat Brown" enamel was a perfect match. This is in the small, cheap bottles. The gray switches were a little harder; I started with Testor's ModelMaster Camouflage Gray and tinted with the brown paint until it matched the original switches very closely.

The finish is not perfect, but when mixed up with the original switches as in the linked photo, the copies are hard to pick out. "Good enough" is good enough.