Woke up thinking about this. Keep coming back to my thoughts above. So am gonna bravely wait and see what you come up with, SB. Har, lol.
There are/is every type of aluminum fitting and pipe. https://www.google.com/search?q=alum...w=1024&bih=494
And fairly cheap; http://www.homedepot.com/s/aluminum%...ittings?NCNI-5
Hmmm. LOL, now this will be stuck in my head all day, SB!
Or to marry non aluminum parts;
Was thinking the cap off a can could be be cut out leaving a skirt/collar and use washers and bolt on like a rag joint. The axle of the wheel would be the cap. Bolted in a circular fashion like a ships doorway/hatch with rivets. Dunno if I am expressing the thought understandably.