Single Flywheel Trouble

I would think that the reason for the shaft breaking is due to whenever you shoot a ball the flywheels slow down momentarily while the motors keeping pushing at full force, putting a large amount of strain on axles for that moment (I’m not really sure where the axle would be you are talking about, a picture would help). One thing teams have done is use a ratchet mechanism so that they can shut off the motors for a moment when a ball is fired and the flywheels are spinning with momentum, but I’m not sure if this is that great of an option. I would also look at possibly reducing the compression of the balls as 0.4" is quite a bit considering some balls are firmer than others, and the high compression will slow down the flywheels.

The biggest thing I would recommend is using high strength shafts. You can easily widen the hole, I would use a step drill bit like this.

Also, as a side note, any lubricant needs to be non-aerosol, so if you are using WD-40 it has to be in the non-aerosol trigger pro containers.

I would think that the reason for the shaft breaking is due to whenever you shoot a ball the flywheels slow down momentarily while the motors keeping pushing at full force, putting a large amount of strain on axles for that moment (I’m not really sure where the axle would be you are talking about, a picture would help). One thing teams have done is use a ratchet mechanism so that they can shut off the motors for a moment when a ball is fired and the flywheels are spinning with momentum, but I’m not sure if this is that great of an option. I would also look at possibly reducing the compression of the balls as 0.4" is quite a bit considering some balls are firmer than others, and the high compression will slow down the flywheels.

The biggest thing I would recommend is using high strength shafts. You can easily widen the hole, I would use a step drill bit like this.

Also, as a side note, any lubricant needs to be non-aerosol, so if you are using WD-40 it has to be in the non-aerosol trigger pro containers.

Your axle is twisting because you have too much compression. 0.4" of compression is a lot and will put a lot of strain on the system everytime you fire a ball.

Agreed. Put another gear box on the other side, reduce the compression rate, use a high strength shaft. Any of these options should do the trick. Hope this helps.

Hi,
No worries about your English. It is definitely more than good enough.
Anyway, mind telling us which team and where are you from?

As for your twisted axle, it is basically a sign of over stressing mechanically.
And this is normally due to either exerting too much torque (over prolonged period) or badly built robots.

Since your robot has gone through 3 competitions, think that should eliminate poor quality of build.

So that means most probably it is due to the changed in your compression. If I understand your post correctly, that your were already having a 0.5" compression, and you added in an additional 0.2". Thats a lot of compression we are talking about here (i.e. 0.7" off a 4" ball) - and that means your motors were working so hard against this additional friction that the shaft is twisted.

Just go relax on the compression.
I don’t think it has got to do with the gearbox design.

I am thinking with four motors on one side the issue might be two motors per axle because stacking four in a row takes a bit of space, if that is the case I think your twist is coming from there. It happened to us in sack attack.