[Travis Schuh]

The dead axles will help maintain the width of the siderail, but I would not consider them a replacement for the stiffness ribs add. Ribs provide a shear wall which helps resist lateral load (parallelograming) and torsional loads, something that an axle alone does not provide much support to. A larger diameter tube coupled with a compression bolt will start to adequately resist lateral loads, but I would not consider a wheel with a 0.5 axle to be a sufficient replacement for a rib.

971 is able to drop our wheels straight out of the bottom because our tensioner blocks space the wheels out past the flange that bends inward. This could be achieved in your design by adding a spacer to the shaft. While a straight up round spacer could get annoying to keep track of and get aligned when putting the wheels in, I could imagine making a simple spacer block that gets affixed to the frame sheet. This could be done quickly on a mill, or even by hand with proper match drilling techniques.

I still think it is important to be cognisant of laser time. It is still costing your sponsor proportional to how long it takes to cut your parts. If they are cutting lights out, then your parts are being cut instead of a customer's parts. If the machines are being attend to while cutting, then someone has to stay extra. Being respectful of their time and money helps maintain a good relationship. If you are interested in saving laser time, I would work on minimizing the number of unique holes. We have learned from our sponsors that the time it takes to pierce the material is significant compared to the time it takes to traverse a profile. Another factor is that it takes longer for thicker material. This has pushed us to going with thinner metal and fewer lightening holes when appropriate, a combination that works well together.