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Calling All Ball Machiners And Knex People! Challenge Answered

I play ping pong ALOT, but since my brothers moved out to college I can't play anymore. I've looked all over the Internet but I can't find any knex ping pong ball thrower/shooter/whatever. So the challenge is (since I can't make one) to create an automated (gravity or motor powered) ping pong ball thrower preferably out of knex. It would be greatly appreciated. Here's some inspiration if you want itHomemade ping pong ball thrower


what about where two motors spin two wheels next to each other and the ball can get placed between them and then flung forward, you could add a track that slides from one half of the table to the side with the two spinning wheels which then resets it :)

Try using a knex trampoline made of rubberbands You need something to fire it at the trampoline and if it is at the right angle it should fly towards you

but if you have to make the ball fire at the trampoline why don't you have it just fire the ball at you?

Well... (Now that i re-think it) I think that it just firing at you would be better... The Ping pong ball does not weigh enough to even push the rubberbands down

actually, rubberbands are a interesting thing. your are right in saying that the ping-pong ball would not push it back that far, but it also does not need all the force to launch it. a heaver ball would push the rubberbands back farther, but it would also have for weight to launch, making it go around as far as the ping-pong ball.

But, the tighter the rubberbands the harder it is to push...

why dont you just play against the wall

Yea I do, the other half of my table comes up, but when i hit it low it goes beneath the table

interesting, it may be a little hard to do. it's not as easy as you think, knex motors can't handle a lot of power. but a ping-pong ball is not really that heavy, so who knows. i might try something out for you in my spare time(i have a project in the making i want to finish). i don't have any ping-pong balls though, so you would have to perfect it your self.

Thanks for considering it, if you have ball machine balls (the red and yellow ones) you can use those, but they're a bit heavier. You could also use wiffle golf balls.

Maybe little a self setting catapult?

exactly what i was thinking.

Great minds think alike ;)

Ping pong balls are light and any impact-triggered launching mechanism is likely to put a nice dent in them. Catapult systems would be effective, but so far on this site we've not had much luck in perfecting the design, let alone a self setting one. Your best bet is to take ajleece's advice.

I may give it a go when I find time.

Hmm you seem like someone that could *thinks about cannons*... turn ping pong into a contact sport...