Plexiglass

[Roamer]

https://www.pellandent.com/One-Eighth-Inch-Glazing-Bead

I think it is this trim, there are two sizes. Rain headed in Tues if u can trust weatherman. I dont have time to order unless I do big tarp that has been blowing off overnight every time… dont get me started. Local RV store had only the most recent trim used on their models, no help.

It has taken 3-4 hours. I cleaned the frame down to bare metal, aluminum prep coat, black paint coat yesterday. The aluminum etcher paint did not work. Now I am working on the rubber. They used the black window goo that never dries, think black booger from hell.
I will try to re-use. Took a long time to get boogers out of channel and off the rubber, then the front was coated with silicone. Got most of it and more focused on the key surfaces now.

I am unsure if I should slather the black goo into the channel, or just apply it where the glass touches the frame. Also, I may apply it like a caulk on the outside rim.

The sealant I have is meant for auto windshields. Its a glue. Local rv place had nothing and auto parts had nothing else

[Roamer]

This is cause for the leak. The window was cut too small for the frame. When adhered in the glass did not have the gap, but it was barely contacting the edge of the frame. The window frame should have been pinched in when installed into the opening, but they did not. The opening was cut a hair too big on top so window bowed up.
I used thicker glass. I think it was the 0.22. It does not flex when pushed on as much as the flimsy stuff. This might have been what was intended for the frame to begin with.
New glass was cut to fit the bowed up shape perfect, so hopefully no more leaks. I used car window adhesive, very permanent. I think the next window change will require a new frame.
I used Rust-o-leum aluminum primer/etcher. It did nothing. Scratched off easily. oh well. looking forward to black paint flaking off on next trip…