Me as well, but I would gladly pay for steel replacement gear for my avio drive since I’ve broken 2 of the plastic ones already.
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Bolts don’t have any angular precision for that, you need pins or something similar, but again hard to clock them good enough when machining
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I feel like if the stacked helical gears was a viable solution, we would see it in more applications. I have never seen/heard of anyone doing that, so I can only imagine that it’s not a good idea.
Then again, I’m no engineer and just because something has “always been done this way” doesnt mean that’s the best/only way to do it.
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Nothing better than properly designed, properly heat treated, steel on steel herringbone gears for this application. Just my opinion.
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this might sound crazy, but what if the design took machining errors into account by creating the locking mechanism such that during assembly there would be multiple orientations in which the 2 gear halfs would fit together, and you choose the one that makes the teeth best aligned.
This would be really easy to do with the larger gear, and assuming the motor gear is fixed already, you could get away with only adjusting the wheel gear to better match the motor gear’s teeth 
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The error I talk about it’s not something you could easily look and see, it’s fractions of a millimeter, this would could leave to just half of the gear actually doing work or the other half just hanging around, plus this could try to move the gear axially and depending on how miss aligned it would cause tons of wear right where the two meet
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A real herringbone gear must be machined utilizing 5 axis capabilities. No way really around that. A double helical gear, which would be a herringbone gear, with a groove in the middle is a little earlier using 4th axis, as you could machine out the radius’s left by the cutter.
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You could “clock” the two parts together in machining, but to much work. I’ve spent a little bit of time on how to machine double helical gears for this application for a reasonable price . I do have 4th axis capabilities, and plan to make a set at some point.
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Didn’t haggyboards offer herringbone gears?
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I did consider using double helicals in this application. The only problem is if you cut out too much in the middle, you take a lot of tooth engagement out of small gears. Since our gears are already not that wide, you might be better off going with spur gears.
Looks really good! How much do they weigh? I see you already optimised a fair bit for weight saving.
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Yeahhh!
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I haven’t measured with screws and other stuff added on, but the mounting collar, cover, motor plate, and wheel hub should come to 0.383kg.
11t gear is .032kg
55t gear is anywhere between .389kg - .471kg depending on how much I end up to take off. Lighter is always more expensive unfortunately. Plastic gears would be around .130 kg or so from what I remember.
I will probably do a lot more optimization before having it properly machined 
I think the trade-off for wider gears would be acceptable, given the extra benefit of no axial loads.
Plus, I’d prefer to not cut a motor shaft if it wasn’t necessary.
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I don’t want to make it too much wider than it already is for a few reasons.
- weight and cost increase as it gets wider
- I still want to be able to fit 63100s on the drive without having to worry about clearance issues
- There is already 31mm of clearance built in for the motor shaft. I think only TB motors are going to be too large. You would only have to remove about 2mm
- I will be making motor spacers that will allow to to push the motor out a bit if necessary
Yup, Haggy and AvX teamed up to produce gear drives, and the V2 series offered herringbones.
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Just go steel on steel straight cut. Full noise, reliable, cheap, easy.
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Blowtorch.
Heat up the pinion till you can see the magic smoke and it will come off just easily.
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Normally I’d 100% agree with this. And I mostly still do.
Except the market already has that option. There is no steel herringbone option yet.
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