Hello master builders.
I'm working on my first large project (and first Lego stack overflow question). I'm making a bridge that needs to be 3 feet long. Unfortunately I don't own tons of Lego bricks.
Working with what I can find, I've built a single supporting brace of #8 rods and #4 angles. (I have the most of these in my bricks tub). Along the top (where the train track sits) are plates. Each platform connecting the plates is a 16 stud gap. The platforms are 4x4 studs.
This doesn't seem to work out the same when trying to pin the connecting beams on the bottom. Below is an early photo, I've reinforced the top to support the weight of my train, but it still bows slightly because the holes in the Technic beams do not seem to line up to the gap length. I think it's off by some percentage of a hole. (That makes me question if the top is actually an even 20 studs between the connectors)
The new design is to have more beams on the bottom and use angled lift arms to shorten the distance by some percentage between the connectors.
The question is, what angle lift arms should I be looking for? And how many variations of lift arms might work. Assume I have enough #4 and #5 rods to pin it all together.
To note, I know that a balance beam for a bridge is probably not a great plan, but I didn't find enough pieces to make two beams across my 3 foot gap. Other suggestions for bridge construction are welcome, but I did search around a bit and either lack the right bricks or am too high off the ground to build support columns (5+ feet high)
Thank you for thinking on this and reading.