Looking For T-Shirt Cannon Help.

Our team is looking to build a T-shirt cannon pretty soon and mount it to our robot to use at the college’s games. I was wondering if anyone had any CADS or detailed designs they could share to help us out. We have seen some pretty cool ones on Chief Delphi like 254’s Shockwave.

I’ll check if my team has old CAD for our former T-shirt cannon bot called “Mecannon Bot.” We have an initiative to build a new one soon, and I have my own ideas for a double barrel breech loading shotgun style cannon bot, which would hopefully be built soon after the next one. So we might have some CAD for the new version too. My team is at CVR right now, so getting any CAD will take a little while.

Here is a pic of our old Mecannon Bot at a football game, which we disassembled a few months ago. The coolest thing about it was that the wheels pivoted up and down, so the front and back of the robot could be raised independently or together, which could make the robot nearly a foot taller. The configuration shown is in the low position. I remember driving it as a student and pretending like it was a car with hydraulics and doing some crazy strafing and wheel pivoting. Hands down the most fun robot 701 has built. Maybe it’s tied with our former chair bot. That too, is going to be rebuilt.

I’m not the op but i would love the cad for that it looks sick.

Independent of the look and drive, a few safety and engineering tips:

  • No PVC. Use plumbing rated for air pressure
    . When PVC fails under air pressure, the shrapnel is terrible. - Relatively large pipes and hoses. Ours has 1-1/4" carrying air for 2 barrels, 1" after the split. The solenoid valve is 3/4", and if we were buying today, it’d be 1".
  • Relatively low pressure - 40-50 psi.
  • Large barrel - ours is 3" i.d. much easier to shoot with the low pressure/high flow.
  • Short burst of air: I think we settled on 30 ms; at 50 ms we sent t-shirts over the press box.
  • Offboard A/C compressor, large tank: I don’t remember the numbers, but a 1 cfm compressor would have to run continuously unless you only shoot a couple of times a quarter.
  • plan for rain. We wound up putting our electronics inside a rubbermaid tote.

We understood the safety risks of this bot, and it was one of the reasons we disassembled it to make a new one that uses components that are fit for use with air pressure. It had no onboard compressor, so we pre charged it with an offboard one before shooting. The new design will be much safer than what we had before. Thanks so much for the tips. We’ll consider these through our design and build process.

Sorry to revive old thread but I thought FRC community should beat the “world’s largest T-shirt cannon”