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Re: Gearbox Question
Our winch works great! Here's what we did.
We use a VexPro 2 speed ball shifter, with the balls removed from high gear to convert it to neutral. We power it with two CIMs. (We first tried mini-CIMs, but swapped out one of the three CIMs on each drive gearbox with the miniCIMs.)
We use a VexPro 1/2" hex shaft for winding the 1" wide military-grade webbing that pulls down the catapult arm. The shaft fits right into the end of the gearbox.
The most significant thing we did for reliable winding is that the webbing is anchored to the shaft at a point about 2" away from the final winding point, so that it winds helically along the length of the hex shaft instead of in a single roll. This dramatically reduces the final diameter of the wound-up strap, resulting in a much lower effective gear ratio at the end of the stroke when the tension is the highest.
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--David Forbes
Mentor, Bit Buckets team 4183. Assistant cat herder and dispenser of legendary tales.
Need a Nixie watch? Yes, you do. Ask me.
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