Hi guys, I need some advice for my team’s flywheel gear ratios. We’re fairly new to VEX competitions, and we would really appreciate any help we could get.
The flywheel design we were thinking of is a double flywheel mounted at around 45 degrees. We were hoping to make it shoot into the high goal from the starting tile at least for autonomous, but we ran into some gearing difficulties.
We currently have a 49:1 gear ratio powered by 4 motors. Unfortunately, we don’t have access to high speed/turbo motors. Would a 49:1 be enough to shoot into the high goal without using turbo motors?
We also need some help reducing friction as our gears are very hard to turn even without motors + they grind a lot.
A 49:1 gear ratio is much to high for a double flywheel.
Most teams seem to be using around a 21:1 ratio with 5" wheels or around 25:1 with 4" wheels to get a full court shot.
It’s very important to get the compressing right, no matter what you do.
I would recommend starting out by simply copying the configurations of other successful designs.
Here are just a few double flywheel reveals in case you haven’t seen them:
These ratios all of you are using, are you already factoring in the internal gears as well? I just want to make sure I’m understanding what people mean when they say 21:1
You say that you don’t have access to high speed internal motor gearing, but when you buy vex 393 motors, they come with a pack of high speed gearing for each motor that you buy.
Totally agree that 21:1 is the sweet spot. A team I am familiar with is currently using a 27:1 double flywheel and have to tone their motorspeed down to 70ish just to stop overshooting the goal!
So use something between 15:1 - 24:1 ish for a double flywheel. Depending on what type of wheels you use / how many you use.
Also many threads have already talked about reducing friction:
Along with the ratios people have recommended, lubricating your gears with white lithium grease and your bearings with graphite will help a lot when reducing friction.
So those of you using 21:1, what internal gearing is that? Regular, high speed, turbo?
Just wondering because we are making full court shots with turbos geared at only 7:1 external, and only one motor per flywheel. But that would be the equivalent of a 16.8:1 external gearing with regular speed gears. Kind of confused why some people are using four motors at 21:1 or more when it can be done with two motors at 16.8:1. Did we just get freakishly lucky with our build? (because we are far from experts at this)
Edit: Just realized that our spin up time between shots is perhaps a bit longer due to only having two motors. But we can shoot approx every two seconds.
I think this is a big one, this year having a fast spinup and a small time between shots will be very important. It will mean the difference between winning and losing some matches. So adding more motors can aid in the area.
