Noiseless drive : gauging interest

wow that video you found @ducktaperules
very good.
Not sure if what is shown is exactly what is being gone for here, totally gave me a grip though
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@Vanarian I see you started this quest with freewheel bearings in mind, I have been thinking about a drivetrain with freewheeling capabilities.
Using either a one way bearing and a disk brake, or a clutch that would disconnect the pulleys from the wheels re engaging for regen braking.
I have a old MBS board with what you could technically call brakes, that I could test both of these ideas on with 3d printed parts.

I would hope this would possibly give greater range on a proper longboard, not that I would be able to test that on the MBS board due to bad bearings and pneumatic wheels

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Bit of fucken light reading for me too I suppose :+1:

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Sorry guys for not answering promptly, and thank you all for the inputs!

@ducktaperules I’ll dive into the links you sent me when I land at home, need more data!! :fire:

Edit : Very instructive informations, will need further readings cause I’m very interested in mixing some designs which I haven’t seen yet!

Lot of unknown factors & it’s important to know the drawbacks pointed out (such as losses at high RPM) which will need extra thought.
Well I’m not starting from scratch either, been tinkering with magnets for a while (I love these things), successfully for some projects so expect me to drop more magnetic stuff here once this drive achieves workable state!

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Yes I’ve been thinking of freewheels mostly cause I need a zero lag variable transmission for my skates if I want to race you all with your monster boards :grin: Swapping stances requires continuous drive from different wheels else I’ll lose half my power while doing so.

I can update you on what I manage to do with magnetic planetary gears à la harmonic drive too, that’s another animal for sure but it’s the same logic again.

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And update just before the weekend :kiss:

Spent 3 hours after day work to get these done, I’ll have few more cut on Monday.

This rig is a bit more “true” size, and will also serve to check a reduction from 8 to 14 poles.

Magnets for the experiment will be 3.7kg each. I expect to play with up to 22kg worth of axial force for a start. So pretty sure this rig will break on the way too :+1:t4:

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So while some of you awesome have had the time of their life at NYEF and shit, I went at it while in the train from Marseille to Paris! Printer is working tonight at the facility (will pick up my parts tomorrow).

And I’d need a little help for wheel core adapter! Do any of you guys have files for pulley adapters? Or some available pulley hubs on hand?

Would be easier and more accurate to design around a proven one. Here’s a quick glance of the thing, nothing fancy tho.

Ratio 3:1 or 24:8, same thing.

Tagging @moon @Riako, I’d gladly have accept a hand for the wheel pulley :muscle:t4:

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Alright for a quick rant :

This thing here, despite being pretty, pisses me off. Polycarbonate retracts madly in an irregular way depending on how wide your diameter is and if there is any material within the diameter AND if there is any airflow.

Which means : all the holes are smaller than they should.

Off we go for another round with correct offsets this time. Great.

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Hate it when that happens :confused:
glad to see that this project is steaming ahead though, im genuinely curious as to how this will work. Keep it up bud!

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I gave up getting holes to he right size a long time ago, easier to just make them nominal diameter or a bit smaller and use a drill to get them right

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I have to say I do the same ^^

Good luck Vana, I will message you in a few hours :wink:

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This is what ive been doing on my Motor and Wheel pulleys. I specifically run my builds with a 3-4 perimeter setting for this reason. its just easier to wait an extra few hours and drill out than account for the shrinkage.

More and more I think to myself that I could easily start Aluminum Casting this stuff rather than using a 3d printer. least it would last longer.

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@Davewesh surprised haven’t see anyone get smooth-0n high heat silicone n make a mold n pour them in maybe aluminum. Maybe not as strong as aluminum. Or carbon n fiberglass n resin w a vacuum. Kevlar n epoxy I’d like to see how it would do. Maybe quieter
Maybe just cast w single flange. Or could probably just fill it, seal it, tilt 90 degrees and back again and get the air out. If u can get the part out.

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I have been considering it more and more, mostly as a time-sink and for being self reliant. Lets face it its going to be much faster to just buy milled/cast parts from the usual suspects.

For direct drive im not sure if the fingers of the gears will survive a hard impact such as landing at speed without good throttle control if they were cast. On the flip side if you just cast belt pulleys/gears (imo my motor pulley is strong enough in PETG) but the Wheel does leave a bit to be desired.

That said, casting a kevlar, fiberglass or carbon fiber (fibre) impregnated gear sounds like it wouldn’t be THAT hard. perhaps tedious… I can imagine laying out carbon fiber layers in the same way that you would print a part. but there in lies the problem - you’d be segmenting the layers in one bias. Which would implicate the strength of the part however, when do you really see shear force applied to the gear face, its all applied to the teeth. You’ve probably made my Fiance’ your enemy @hummieee I’m thinking ill go look at some vacuum pumps after work today.

Another thought occurs, more in the detriment of this approach that i think of. Good luck making sure that the teeth are consistently in the right place when laying down layers of CF during the build out process for a gear. So forget everything beside spur gears and maybe Timing Pulleys. Less of course you use impregnated resin. hmm all these options. Ive got some brainstorming to do.

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Alright, fuck that retraction.

For convenience I did half print half laser cut, no more tiny holes. To be followed next week! :beers:

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You Shall Not Retract! Finally my holes are right. Cause even the laser cut was failed, not enough material between each pole (thank you plastic).

Next story soon.

Lesson learned : pierce hole to allow air.

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Great project you got there vana, why nothing on the french forum :wink:
Really curious about the drag it will cause having permanent magnet so close to each other

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Thank you!! And that’s because I’m lazy :sob: no excuse really lol

A vrai dire j’ai tellement de trucs en statut “en cours” sur le forum fr, pour une fois j’ai envie de poster un truc un minimum “fini” :sweat_smile:

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So guys I’m really looking for wheel core dimensions / patterns since I don’t have a pulley at hand currently! Could boost tremendously the speed of the process so instead of doing multiple dummy iterations I can test straight with mountable versions. Hope it’s not a prized manufacture secret :joy:

@moon might have some on hand.

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@moon sending you a Whatsapp my man!