[mott]

Just a quick follow-up on the suggestion about the corner braces assisting with the welding...

As the mentor who handles most of the welding for team 1730, I would NOT recommend riveting the corner brackets into place before welding the frame. Doing so would create 2 "three-wall" pockets at each corner of the frame that are very difficult to weld (especially without actually welding the corner gussets in with the 2 frame members)!

I'm sure every welder out there has their own preferences but my suggestion on "helping out" the welder on a frame like this would be to make 2 "jig bar spacers" that are the exact length as the space you want between the left and right frame rails. Your 4 perimeter frame members can then be clamped together with 2 bar clamps in each direction (using your jig bars near each end of the side rails) to ensure you are parallel left to right. Then, with everything clamped together, you can verify you're square and weld.

Other Hints:

If possible, keep all your clamps on the same side of the frame, this allows getting a big framing square on the other side without obstruction (and allows easier corner-to-corner measurements as well.

Depending on your eventual frame design, these "jig bar spacers" can eventually become inner cross-members of the frame itself. Once your perimeter frame rails are welded, reposition the jig bars to where you'd like the cross-members and weld them into place as well.

If you want to use corner braces in addition to the welding (we actually haven't on Team Driven's frames) you should consider NOT making them triangles as you're probably better off without the 90 degree corner on the gusset where it would interfere with the face-welded joint of the 2 frame members.