Remember that you can get the same linear velocity out of your shooter at lower RPMs by going to a bigger wheel.
Do you know where we can find some 6" or 8" wheels?
From FRC suppliers, you might want to try the AM Smoothgrip wheels.
If you’re willing to search elsewhere, you may be able to find some 6" or 8" Colson wheels that work with the hubs that VEX sells.
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Thank You!
https://thaddeus-maximus.github.io/swissarmyengineer/hooded_launcher
Something to chew on
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For example: https://youtu.be/vx6qHOrdovc
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Looks like we should start looking for some old bike wheels!
Take high speed video of the ball going through your shooter and look for places where it isn’t accelerating smoothly. Make sure you have as long of contact with the shooter wheel as possible.
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This post of mine may be helpful to you in designing a good one wheeled shooter, shooting farther, and more consistent:
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For reference, a “super speed” heave duty milling machine, surrounded by a thick steel enclosure runs up to 12k RPM – for high strength metal tools that have to be very well balanced.
20k would likely result in the wheel failing in an unsafe manner, and would likely shred game pieces pretty badly. If it all worked, the game pieces would become missiles.
5k is scary enough, unless very well executed. 
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Thanks! Definitely started to look into more reasonable speeds in the 5k-6k range. What does your team use as a flywheel, and what do you do to keep your flywheel safe?
We used a 6 inch colson at 3800-4200 rpm for shots consistently from just in front of the wheel. We balanced it on a lathe with a little creativity, luck, and a mower blade balancer. We used a relatively flat trajectory and could have shot further had we aimed higher.
I had no qualms about spinning the wheel at 5k rpm, but we had a tough time getting the ball up to speed with the wheel to make it consistent.
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Alright thank you!
We use a 6" HiGrip wheels at 4-5krpm on standard 1/2" hex hubs. Might have been Vex hubs, might have been AndyMark hubs, I honestly don’t know.
We didn’t do anything specific to balance our flywheel, though a factor in choosing the HiGrip wheels over Colsons was that we (read: I) pressed one of the hubs for a Colson ~1 degree off axis, and we (read: I) didn’t want to spend a lot of time trying to balance it.
There were no issues getting the wheel up to speed, and once at speed there were no issues with it being off balance (not a lot of vibration, clear circle for the wheel edge, etc.)
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Thank you! If you would be comfortable sharing, what motors did you use and how long was the spin up time and time between shots?
2 Neos, geared at 36:24 from what I remember. Spinup time was about .3 seconds, and the lowest recovery time was somewhere around .15 if I’m remembering the numbers correctly. We ended up shooting about every 3-4 times per second.
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Thank you!
We’re using the 6" HiGrip wheels, and with two Falcon 500’s we’ve had it up to 7500 RPM without issues (we’re not actually running that fast in practice). We did, however, need to balance it to prevent excessive vibration.
Thank you! How did you go about balancing it?
I asked the mechanical gurus to balance it, and it magically happened.
They used a device normally used for balancing grinding wheels, I believe. Something like this.
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