This past weekend at the FIM Macomb District event I found this Aluminum Spool in the spare metal tub at the machine shop. I was wondering if anyone might have an idea of where I could purchase more of these? We don’t have the capability to make one currently. Thanks in advance.
I would bet a decent amount of money that a team machined that as a custom solution for their robot.
You can make that with a mill or a lathe and also an arbor press.
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We stack two hex bore VersaHubs together for winch spools. VersaHubs (8 Choices) - VEX Robotics
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I think there’s a part in this kit that does what you want, the West Coast products telescope kit probably has a similar winch component as well somewhere in it.
Historically, we have stacked 2 hubs together the way Everette describes and had it work fine.
You can make it even better, if you take some of this extrusion, you can press the hubs into either end to make a seamless spool: https://www.mcmaster.com/9056K76/
Just make sure the hex bores are aligned.
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Thanks for the idea. We are having an issue with the rope getting wedged into any nook and cranny it can find due to some extra force we are exerting on the rope in our specific design, so we’d like to find a single piece spool if possible.
We are currently using the Cimber in a Box Winch Kits but we are exerting some extra force on the rope which is causing it to get stuck in the splits between the spool pieces and the spacer in the middle. Having a single piece spool would be awesome.
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We’ve made spools by stacking hubs for years. Typically, we’ve used AndyMark hubs, but this year switched to Thrifty Hubs. One issue we’ve found with this in the past is the center, where the two hubs meet. If you’re using a thin rope, it can squeeze between the hubs and cause problems. To avoid that, we put one of the hubs on our lathe and cut the 1 1/8" portion off, then cut a shallow recess where it was. This allows the other hub to nest inside of it, just slightly, and provides no place for the rope to get stuck. It’s been working perfectly!
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We made our own just took the extruded aluminum and drilled 2 disk for it to fit in and welded it together on the outside
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Same experience here, ours gradually wedged apart after a few cycles of hanging and eventually led to the cord fraying and snapping, resulting in a fall, thanking our lucky stars it was only from the low bar. I would greatly prefer a single part solution.
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It’s suprising that there isn’t a good COTS .5" hex spool by this point. It would be pretty thrifty to have something to fill that niche.
Ahem @Ryan_Dognaux cough cough
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If you can adapt this to a hex shaft and package it there is probably no better option.
We found the best way to deal with the “rope getting bound up everywhere” problem was to change to flat webbing - not always applicable, but nice for climbers. We use AndyMark hubs as winches with the webbing and it works well.
I have seen teams 3d print winches, but I suspect the loading for you is beyond what plastic could handle.
That depends entirely on the plastic.
We’ve used printed spools for our climber, but they are printed with carbon-fiber reinforced nylon.
Any links to flat webbing?
Ratchet straps from Home Depot / Walmart. Even the cheapest ones are rated to 300 lbs and usually have a convenient loop in one end. Just cut the metal hooks off.
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On our recent winch style climbers we’ve been avoiding spools altogether. We just let the cord wrap around a length of 1/2" hex long enough to contain the entire length of wrap to do the job. I think we started this practice in 2017 with the winch to climb the Steamworks ropes. We started with a spool made from a boat trailer bow bumper. It ended up splitting in half, and we found that the winch worked just as well or better with the rope wrapping on the bare shaft. With the diameter small, it required less gearmotor reduction. With no sides to constrain the rope the effective diameter didn’t build up, so your motor torque didn’t increase as the winch ran. And with no seams, the spool didn’t want to come apart. The only drawback is that the shaft needs to be fairly long. In 2020 we returned to a spool for our winch driven climber, and 3D printed the spool. I don’t remember the material, but it was good stuff. Trying to find out what it was. It worked well for testing purposes and our one competition, but it showed wear from the bearing stress. Making spares was easy, though, and it could be considered a consumable part to be changed out before each competition.
This. Our AndyMark spool pushed apart from the rope making it into the seam, and the spool edge brakes against the winch plates we used. We didn’t use the whole climber in box kit so ymmv.
We did do something like this but with stock we had. Ideally a solid spool like this post would work well.
We had success with the versa hubs as a spool by bolting them together with two small bolts
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Our spool is 3d printed with Ninjatek Armadillo. They’re holding up well, but we have two arms, so each one only takes half the weight, and our robot is pretty light. However, they’re two pieces so doesn’t help here.