Well the diameter is about .7 inch I think, standard small 3vdc motor. With a cotter pin the pin would hang out too much and hit my frame and also I'm not sure it would hold the axle tight enough. Good idea though. Still need help, anyone?
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The set screw idea kind of backfired. I bought one, the hole was too small. Where do you get set screws, and cheap ones too because I bought one and it was $6!
I was thinking about trying epoxy, just fill the top of the poland spring bottle with it, let it set and drill it to axle size and use 2-3 setscrews I drill in the sides. Will that work?