That looks great. I like that you have the left and right sides touching the Z pipes symmetrical. That should add a lot of strength, plus, it looks cooler. Seeing it without the nut trap, I can see why that’s difficult to get attached. So are you making it attach to the 4 (or 2 of the 4) nearest bolts, instead of using the small screws?
I was sort of surprised when it fell down, because I thought it would have had a physical trap, not just gripping it with friction. But once I printed the correct size, it seems to be very sturdy.
If you end up with a silly nut like that again, maybe you could design a wrench that I could print to help me out :).
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