REV Ultraplanetary

[FTC14752]

Before I make a huge error.....

I have a REV ultraplanetary built with a 1:1 gear ratio and a TETRIX Max 4" Wheel. The current installation (handheld) is being used for testing to determine if we want to use 2 motors and if we are going to need to be able to adjust the launch angle based on shot selection.

1. I have a lot of vibration -- final plans call for a top plate with the shaft through a bearing -- am I missing a build basic or trick?
2. The screws that hold the ultraplanetary cartridges together are vibrating out -- I can add loctite, but am I using the wrong length screw (how do I know)?
3. It sounds like an old gas powered RC engine -- is this normal?

Any advice would be welcome!

[ftcsachse0]

I don't see anything amis in your picture. I would guess that your wheel is out of balance. Before tightening was there any play in the hub? We are running the same motor spinning a Rev wheel and it has some vibration but nothing like your speaking of.

[alan_16072]

We see a lot of vibration in our setup that is like yours. We traced it down to not having a top plate with the shaft through a bearing. If we run it a while (less than a minute), it will settle in but when the ring touches it it knocks it back out of balance. Our suspicion is that supporting the shaft from both ends will solve the problem.

--Alan
Coach FTC #16072, Quantum Quacks

[alan_16072]

Uhm, this is embarrassing to admit but I had a student that figured out we had neglected to put the set screw in to hold the shaft in place. Doing this dramatically reduced the amount of vibration. Perhaps the instructions should be read.....

[FTC14752]

My girls are not liking the instructions. The students (6th grade) also initially forgot the set screw -- this was caught as well as the fact that they mounted the motor directly to both a motor mount and the frame in the mentor review before firing anything up!

[alan_16072]

FTC14752 - What does a "mentor review" look like and when do you do it? This sounds like a very interesting idea.