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Originally Posted by sanddrag
Would it work to just have a plain bore through the gear, but have a hub of diameter of .375 with 4 slots cut in it at 90 degree intervals and then use a split lock collar to clamp around that to affix it to the motor shaft? Would that hold (not slip) at motor stall? I suppose I could just try it, but I don't have a motor. I could do a little mockup with a similar shaft to the motor shaft and then use a torque wrench or something to move it while holding the clamping collar in a vise.
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I like this idea, but would recommend a 7/16" hub outer diameter and just two slots 180 degrees apart. This gives (7/16" - 8mm) / 2 ~= 0.062" hub wall thickness. Then the hub stress is carried by a steel thickness that is 0.062/0.048 = 1.28x the tooth thickness -- not up to Joe's 1.5 standard, but much better than you'd get using a 3/8" hub.
SDP-SI shows 17 tooth 32DP pinion wire in carbon steel, p/n A 1C 9-N32017 out of stock now, but the dimensions look right.
McMaster has nice 7/16" collars for a couple of bucks; e.g., 6435K53.
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