Here's a tip for anyone doing this
Hadn't done of these for years, but had 2 recently, one for 41 blinds, the other for 55. Roof beams were very deep, and it was very difficult to get a screwdriver in, as both customers wanted the blinds
as close to the glass as possible.
First one we used a face fix bracket one side and a bent L bracket the other.
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\ Ignore the dots, this won't let me use spaces
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\ lProblem was that due to the compound angle of the tapered beam, the brackets didn't really line up and it was very difficult to actually get the top rail in.
For the second we tried the back half of a UEB, but this bent when the blind was tensioned, and couldn't be directly fixed on the other side as the side rail comes up between the top rail and the tapered beam. We overcame this by putting an L bracket so the side just caught the end of the UEB, stopping it bending. The UEB has the 2 holes already for the top fix brackets, so the rail snapped in easy as anything.
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\ bracket is 90deg but can't draw it here
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