How to make slipgear

My team is building a cata and we were wondering about the best way to make a slip gear. How many teeth should we remove and should I remove them in one section or two sections? (We are using a 36 tooth gear)

Your amount of teeth depends on your design. I’d say to get the catapult built then grab whatever slipgears you already have and try them out one by one seeing if any work, then altering the closest to get it exact.

While you can certainly try slip gears you already have, I would start by building your catapult frame with a full gear. Then test its arc of motion to see which teeth the gears are contacting at on both ends. Mark the teeth somehow. Take the gear off the bot and sand down the teeth in between the ones you want it to stop and start its rotation at. You can sand them down with really any sort of grinder or sandpaper, even files. It just depends on how much time you want to spend. Keep in mind that this is just one method of many regarding making slip gears, and I’m sure there are others that are just as good or even better.

I find it unlikely that you’ll have enough teeth left to get to multiple slip sections, but that just depends on your design. If you do, making another section will probably decrease the cycle time for firing, but again, that’s up to you.

A lot of this will come down to testing, and I encourage you to try it and see what works. Good luck! I hope this helps.

I just experimented with my first slip gear a few days ago and basically followed the procedure outlined by @Keys and it worked well. (I used a small band saw and then sanded.) If you are not sure if a tooth should be cut near the edge of the contact zone, leave it at first. You can always remove it later, but the slip gear is essentially useless if you cut too many teeth off.

Unless you’re making a very large slip gear for some reason, you probably want just the one slip section. It will rotate through fairly quickly under no load… but it is design dependent.