A couple months ago, our team decided to try a linear puncher. We built one successfully with 2 393 motors on a 36 tooth gear running directly. (10 tooth missing for the slip gear.) Despite this, our puncher was weak and decided to only mount our puncher mounted in one position (the low flags). Our puncher could only turn the middle flags from about 3 feet back.
In order for us to be able to hit both flags, we created a device that can change the angle of the puncher, and we added a 3:1 external gear ratio to the puncher. Our puncher can still hit the middle flags, but it just can’t shoot far enough (or strong enough) to hit the high flags. Putting more rubber bands doesn’t really help it go farther, and I don’t know what to do.
Our goal is to be able to turn both high flags, Any advice would be greatly appreciated!
Try this: Remove the rubber bands. Manually move the slip gear so the slider can move freely back and forth and check for friction. If you have too much friction and you are using those green plastic bearings to support your linear slide, then see if those bearings are out of alignment. If so, consider loosening them ever so slightly so they can, in effect, find their own path of least resistance. Also, consider putting a little bit of lithium grease on them.
Try adding stronger rubber bands. It looks like the rubber bands you currently have one don’t use most of the rubber bands potential energy because the puncher is too short.
at 1:3 with double motors and adequate rubber bands, the only thing i can really think of is an inadequate transfer of power. This can be caused by friction or by rubber bands not placed in the right spot. Judging from the picture, I thiiink your rubber bands are in an okay spot although it’s a bit hard to tell without seeing it in action.
One thing you can definitely try is to shave the slip gear down more. The rack gear might be rubbing against the gear when it slips. My gear looks like this
you don’t have to go this ham on it but you’ll probably want to cut into it more
Ok thanks, I’ll try using some grease. A section of the slides have been slightly sanded down to reduce friction, but there is still a tiny bit that catches at the end.
We found plenty of power when we built out 1:5 puncher. It can do full court shots and only uses 1-2 rubber bands. I could post photos/videos if someone wants them.
Everything looks reasonably built. Your problems seem to me like they stem from either contact point for the ball or friction. Friction was pretty well covered by @FullMetalMentor and I don’t see anything else that would really create a problem right off the bat.
If your lithium grease doesn’t work, maybe try messing with where your puncher actually makes contact with the ball. Isaw a thread a while back that may be helpful if you need it. I don’t really want to go searching for it, but I will if you need it.
