You can do anything but the inside is supported by randomly placed little blocks of scrap. The whole idea is to reduce the weight and cost. How heavy is your window? Plexiglass might be ok but nothing with any weight because unless you used some kind of a u shaped channel or trim on the outside it won't be secure enough to handle the movement with opening and closing the door itself. J MO
Our 14 year old cord controlled blinds are all giving us trouble with raising and lowering and tilting. Many of the top mechanisms are coming unglued from the top. I ...
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You can do anything but the inside is supported by randomly placed little blocks of scrap. The whole idea is to reduce the weight and cost. How heavy is your window? Plexiglass might be ok but nothing with any weight because unless you used some kind of a u shaped channel or trim on the outside it won't be secure enough to handle the movement with opening and closing the door itself. J MO