I'll bite, go ahead and build your wheels, and when you are done in a year or two you can buy some like I am about to after 3 seperate attempts to build them. my last set are only $150 + $300 design cost. I'll send you the plans (you can build them for $150). they are heavy (5-7 lbs more than cat trax) and no one on the beach will help me any more when I come ashore by bringing them out to me. and they do not work in deep sand. I could make a modification to make them better in the sand but I am done already, time to buy some real wheels from cat trax or sailcraft (mfg). Money well spent.