Interesting. Angle it will be then.
What thickness? Quick scan of ebay for supplies suggests 3mm or 5mm are readily available.
On building the base section, do you recommend the 45 degree cut and butt weld, or overlapping and welding all the seams?
I was envisioning the angles being the other way up, with the tubes welded into the corners. Does it make any difference?
By 45 degree plates, do you mean gussets, reinforcing the tube to angle joint?
The top tubes are slightly more complicated than my diagram suggested. The arms are from an existing bike carrier. These terminate with 1" ID box section, which slide over 1" ID box section on the main frame.
I also want to put these arms on a horizontal slider (tube over tube or box over box) to give some adjust-ability to the arm width.
Part A can slide left and right and will be held in place with a bolt/quick release pin.
Part B is the Pre-made arm that will slide onto Part A, also held in place with a bolt/pin.
What recommendations have you got for this section.