My team is a rookie team and we are trying to figure out what gear ratio to use for our flywheel. We tried 11-1, 7-1, 5-1 and none work. Any suggestions?
5:1 usually is a good ratio, what motor cartridge are you using? If you are using a blue, then 5:1 should be good, if you are using a green, then you’ll need a ratio 15:1 to do the same speed, which will be a compound ratio of 5:1 and 3:1
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We tried with a blue
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5:1 or 7:1 should work, but it could be a friction or some other issue, and if it was a friction issue or misalignment, then a picture would help. Another thing- what do you mean by not working? Not shooting a disc or just not spinning at all? Check if the motor can spin without a wheel or gears. Check if the axles can spin without the motor too. If the motor can’t spin without wheels or gears, then it may be a port or motor issue. If the axle can’t free spin without a motor then it may be a friction or misalignment issue.
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Actually I just checked the gearing in a calculator and it isnt 5:1 so what would be the optimal gear usage?
60t:12t is a ratio of 5:1 which is usually pretty good, and 84t:12t is 7:1 which is slightly faster, but I would personally recommend 5:1 ratio which should get you to 3000 rpm with a blue cart.
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Thanks sooo much! That will really help us
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pay close attention to flawless assembly methods and keeping friction as low possible.
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To add on-turbodog, your topic about quantitive flywheel analysis is a great topic to check out!
dont use any gearing at all trollface.png
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There’s a new way to use motors in vex now since of a new rule that allowed you to remove the cartridge and use a custom adapter to make a direct motor to flywheel connection. Vex motors are 3600 by base, and cartridges reduce the rpm for torque. So if you want to try a 1 motor flywheel, I recommend just using an adapter.
our team is using a 7:1 gear ratio with a 84t to a 36t to 12t gears which all run pretty smoothly and can get up to 4200 rpm
(old photo will get a updated photo later)
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This is good if your using a 3inch wheel but if your using 4inch 3000rpm (5:1) is alot better
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Ok I’m assuming you’ve done all this I’m about to saysince this is an old photo, but:
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Needs support on both sides of the c channel. I would suggest having the c channel flipped over 90 degrees either way from where it is now, so you can put four standoffs instead of two to increase the quality of the flywheel. You wouldn’t want to sit on a chair with two legs.
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Should use shoulder screws on the stand-offs. They increase alignment by a lot and single handedly made our flywheel work. Definitely an essential for a consistent flywheel. If you don’t have them i think there’s other methods to do alignment.
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Needs 2 bearing flats per axle: you have no bearing flats, and I’m assuming you’ve put them on already but just in case you greatly need that.
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Needs an extra c channel with a bearing flat to support the wheel. Use shoulder screws to attach it.
Dont know about the quality of my flywheel, but i think it’s good. Ignore the uncut metal.
Note: there is bearings for the axels they’re just hard to see.
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thanks and yes i have done most of those now side note what cad are you using?
why do you have a 36t gear in between the 12t and 84t?
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its an idler gear just to transfer motion
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Also sucks up some power due to shaft/bearing and gear tooth friction.
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if your just doing 1 motor then you either want 3000 rpm or direct 3600 rpm. 4200 would probably have issues when running off of 1 motor. Personally I would suggest 3600 direct as it has very little friction when compared to other designs.
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