Early style piano-hinge window frames are made of chrome-plated brass. Ours had a little pitting on the outside surfaces, but since the frames are identical it occurred to me that it would be easy to swap sides, so the pitted surfaces were facing inwards. While swapping the frames, I could also replace the rubber seals.
How difficult could it be? Very, I discovered. A strip of rubber has a *lot* of friction when compressed, the frame wants to twist and spit the rubber out, and the glass is toughened so you can’t put too much stress on the edges. It turns out that the factory used a hydraulic press table to assemble the damned things. I don’t have a hydraulic press table, but I do have a number of cargo straps. Eventually everything fitted into place.
I will let the rubber seal settle for a few days before trimming it to size, but everything seems to fit nicely.