pic: 3 Hour Chassis + 2 Hours

[548swimmer]

It's looking a ton better!

You'll need some way to attach the tube supports to your outer plate. We use 1.5"x3/4"x3/4" press-fit stock tapped with 1/4-20 to do this.

The tubes should have material underneath them. There's no constraint tool in real life, so spacers have a hard time just hanging there. Think about the assembly process when you're designing robots, that helps me the most. You can usually just pound them through with a gentle persuasion tool if the hole is a tad small.

If at all possible, the design would be a lot stronger if you move the tube supports so that they are not all along the same line.

Are you running both chains on the same side?