Very exposed large spiders and secondaries have a tendency to quiver rotationally in gusty wind, the result being elliptical star images at high power. Splitting the diagonal into two 'L' shapes, per Texereau's suggestion in his book, How to Make a Telescope, anchors the diagonal holder so that it can no longer rotate. I also removed large sections in the middle of the spider vanes to reduce weight and to avoid the thermal problems of metal radiating to the night sky where a thin layer of colder air forms around the vanes, leading to increased diffraction. The 20 inch is ramped in and out of my pickup. Total weight of the truss tubes comes to 6 pounds.
Wooden plugs fill the ends to prevent their collapse.
The upper ends of pairs of truss tubes are tied together to a block of wood so that I slide the upper ring onto four bolts extending from these blocks, the truss tubes folding parallel for transport. And now a word about truss tubes and their function. Truss tubes hold the upper ring by compression. The goal is to pick a truss tube diameter so that the compressive forces do not buckle the truss tube. A perfect truss tube design would taper at each each, with the fattest part in the middle.