Maybe I could drop the whole build back to using only HD 45 extrusion?( 45 x 90 for the sides and gantry.)
Would be alot cheaper and there are a lot more size options...... as long as it would stiff enough.
Can do some simulations in Fusion I guess.

I am a little concerned about attaching 45 extrusion to side plates using just the 2 holes in the centre. That does not seem the best idea.
Is there any way to utilise the square hole in each corner?
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