catapult skipping

I need help our catapult skips.I change the rubber band place and i change but can not get a lot of power

Can you clarify what exactly skips? The gear over the rail or could the rail be hitting something else?

Did you try to add more rubber bands?

Chances are that the axels aren’t properly supported. Do you have pics?

I can give you some. If i add more rubber bands it skips gear. but if it has less it works but not a lot of power

i will get a video

Make sure all of your bushings are tightly secured to the bars if one slips it could be causing the gears to not mesh properly. Also if you are not using high strength axils I would recommend pulling them out to see if they are bending. Lastly, make sure that the space between the two bars that hold your catapult arm/gear is as small as possible. This will reduce the axils flex and help the axils mesh better.

Hey Logan, I spent around a week prototyping catapults of all designs and a couple tips to prevent slipping until you want it.

  1. use sprockets as the slip gear
    2)the banding should be pulling the catapult towards the gears, so when it is drawn it pulls them together under the load
    3)Depending on your setup, it may look like you catapults and driving gears are slipping, but sometimes it is the motor to gear ratio.
  2. for us, we used standoffs as the axle as vex axles are too flimsy.

These solutions is what I have learned over continuous generations of our catapults and now it can launch 2 balls over 20 feet and we can launch a lot farther, but it turns out the flags ricochet from blue to red then bounce back to blue with that much power. If you need a picture, ask. I would be happy to help.

using high strength shafts would probably fix your problems

we have high strength on the big gears
Screenshot 2019-01-25 at 8.13.26 PM.png

another one
Screenshot 2019-01-25 at 9.03.59 PM.png

try using HS shafts on all the gears you can