We built one piece bumpers this year; we have a blue set and a red set. Wooden bumper elements were made on a CNC router and are joined with screws with aluminium plates at the corners for strength. The bumper is supported the whole way around by a 25x25x1.2mm Aluminium tube frame perimeter. The bumper is attached to this tube with small angle gussets using M5 bolts and wingnuts. We are using conventional Cordura bumper material for durability(even with this material they did get a few tears and punctures at the Australia Regional) and did a lot of searching for the firmest Solid core pool noodles. Because Australia is in the Southern Hemisphere, summer is December to February meaning that Pool noodles are widely available just when we need them.
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