I have wanted to build a lowboy for awhile, but kept being put off by how to create the "angle" of the frame at the rear, (that the suspension attaches to). I don't have the facilities to mill out an angled frame, and have been looking for some type of suitable angled bracket I can use, (I didn't want to use 90 degree corner brackets). I recently found these 135 degree aluminum brackets that are used for robotics builds, and think they might be just the ticket. Height of the straight part is 1" and thickness is 0.080". When you "invert" two against each other to form a zig-zag angle, you can change the top-to-bottom height from 3" to just about 4-1/2" by changing which holes in the two plates line up with each other. (Sorry, I do not know how to do photos, so I hope I'm not just confusing people). Cost is two brackets for $3.99, and I ordered four sets in case I have to double them up for strength. Their website with a photo is here:
https://www.competitionrobotparts.co...racket-2-pack/
I hope that these will allow me (and others) to build a trailer that they weren't able to before. -Mike