Yes, Travis is quite right, I neglected to mention that our wheels have always been mounted such that they could slide for us to tension them. What I intended to explain was that spring tensioning is not the
only solution, and that slots are a convenient alternative.
Also, note that Bosch extrusion particularly has very easy, built in slots that hold well (if you are using 30mm X 30mm, that is). There are T-Blocks available (at great expense
) that make mounts very solid.
Even if you do not wish to use Bosch, and you don't like your chassis to have a big aluminum plate base, you can still use slots. Take your welded chassis and bold on a plate, almost as a gusset, but with a big slot and two smaller ones on each side to hold the wheel and two mounting blocks. The slots on the side allow you to adjust the mounting block position. But it gets better: many teams have trouble tensioning this, because it takes two people: one to pull on the wheel and one to tighten, and it just isn't fun. The clever plan is to use a custom tool. Mount a block with a threaded hole in front of the mounting block slots. Use a larger hold for greater control and ease of use. Then take a long bolt and put it in the thread, so that when you tighten the bolt, it will push on the mounting block. Then you can even use a drill (on very low clutch setting, maybe as low as 11 or so) to tighten the mounting blocks for you, and they won't bounce back. VERY useful for quick tightening jobs.