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By using the concept shown by NMech, you shall be able to set up two equations as shown below, then solving for L.


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ISO 2768 is a good pointer towards tolerances on lengths, angles and some geometric tolerance things. Engineers Edge have bits of it tabulated here. It's only valid for machined parts but it's a good start. There's an equivalent standard for welded parts, castings and presumably polymers. Generally aim for 'medium', I'm yet to find a machine shop that doesn'...


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3rd edition Marks HandBook circa 1923 is what I use. When the local library re-opens, check out the modern versions in the reference section.


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There is no reasonable way to prevent 'destructive' access to the box by 3rd parties - cardboard is too easily cut, and putting each cardboard box inside a steel box defeats the purpose of cardboard boxes. The best you can achieve is secure them in a taper-resistant way, something that won't allow easy access without "leaving marks" and provides ...


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The boxes can be strapped using plastic strapping as illustrated It may give you peace of mind but as @Solar_Mike states such straps can be cut and replaced by anyone who has such straps and the tools to apply the straps. If they don't want to replace the straps they can just cut them or cut a hole in the box with any sharp knife. By strapping the boxes all ...


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You can't lock something that one can gain entry to with any craft knife. While the no-tape box design is novel, taped boxes work well and can be re-used again and again. The tape doesn't ruin it, you just tape over the tape the next time.


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The biggest issue to having a 'standard' solution is that there are so many different sizes of boxes. If a standard solution is adjustable, then that presents a point of weakness. Since "It's just stiff paper" so if someone wanted to actually protect the contents, they would have to surround the box entirely. That all said, many people have ...


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Ok I think I understand the intention now. Here is a thought of how to do it with timing belts. 6 half axles and 2 common shafts M1 and M2. All 6 half axles would all need to be horizontally adjustable to tension the 6 belts. Everything could mount to "2D" vertically oriented sheet metal or laser cut parts, and the same shafts, bearings, and ...


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There are several possibilities depending on what it is you are trying to achieve with your motors. As Pete pointed out, just syncing all your wheels would KEEP things the same phase (180 deg) apart. Next up: the thing your diagram seems to represent - two sets where two outer 'wheels' and the middle 'wheel' of the opposite side are in sync. This allows you ...


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There are standards. But that's really putting the cart before the horse. Imagine you're designing ..anything. By default the tolerance is whatever you can expect from the fabrication process if everything is done very poorly, and carelessly. Is the part still acceptable? If so then you're done, no tolerance needed (practically speaking). Most of the time ...


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You can easily measure this by dangling a weight from a string and winding that around a pulley of known diameter. This arrangement will produce a fixed torque on the pulley, which you can adjust by changing the weight. Now all you have to do is attach a knob to the the pulley and you can feel what a given torque is like. Adjust the weight until the torque ...


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It really depends on what your application requires. Sometimes the optimal layout isn't feasible so you have to use what is. But here are some general rules of thumb to add on to NMech's answer: Typical maximum ratio is 5:1 or less for parallel axis spur gears. If your gear radius of curvature is significantly greater than your pinion, you'll have ...


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I think you've most criteria covered for the case you are considering in your post. The only criterion I haven't seen is wear and tear. Regarding wear and tear there are mainly the following considerations: the first is that the smaller gear should not have less than 11 teeth under any circumstances (preferably not less that 14 if possible). Usually 17 ...


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To my understanding that is the main requirement to minimize as much as possible tear and wear, is to have only one of the two components loosely fit on the rotating shaft. So in principle, both solutions you are considering should be fine. To my mind, the main drivers for the choice come from other considerations. To avoid confusion, I will hereafter refer ...


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Assuming the same material and tolerance, I pick the right-hand detail. Due to having a larger resistance arm against shimmying and lateral shock when the wheel falls into an unsymmetrical pot-hole or passes over random construction debris like broken cinderblocks, pieces of metal, pebbles, etc. remember direct loading stresses are secondary to lateral ...


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