How do I add power to K'nex motors?

I'm working on a K'nex automatic machine gun. Unlike most K'nex mg's, this one fires from a hopper and does not have a barrel for every round. Unfortunately, it doesn't work because the motor can't pull back the rubber band. I have one of those clear motors with a red battery pack. I was thinking to hack it so it would take a 9-volt, but i'm not sure if that would work. If anyone can give me some advice, that would be good. Thanks.

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23GUITAR059 years ago
Yah all you need is to make a gear box
bakenbitz9 years ago
Its called a gear ratio.
theperson29 years ago
use the newne type of motor or the black motor from starburst spinner and add more torque once more that should suffice could someone please start a forum on ball factory's
Pax4159 years ago
I went on knex.com and clicked on videos. One of the videos was a tip on making faster vehicles with a motor. It said something about putting a large gear on to the motor and a smaller gear to the thing you were trying to move or in this case, pulling.
Namlem (author) 9 years ago
OK, so i experimented a bit and discovered that my efforts have been in vain. I used three clear motor, but the rod just slipped inside. I guess I'll just have to use a weaker rubber band. I was hoping for something a bit more powerful than oodalumps' gun, but I just don't know if it's possible.
gyromild Namlem9 years ago
It is possible.. Just remember, using stronger rubber band means you need a stronger motor.. Try sourcing for high-torque motors.. Last resort would be hand-cranking it.. :)
Namlem (author)  gyromild9 years ago
It's not the strength of the motor that matters at this point, it's how well it grips the rod. The clear ones can't grip the rod strongly enough and the force of rubber band overcomes the force holding the rod in place after only about a centimeter or so. While hand-cranking might work, it would require me to add a lot of extra parts to the gun to increase stability and durability. Also, it would be a hassle to use it.
gyromild9 years ago
First of all, you cant really go beyond the torque (put simply, the spin strength) of the motor. To compensate for that, you gonna have to use either, gear system, lever & fulcrum, or pulleys.. Simplest set up for a gun (like loosewire said) would be attaching a small gear on the motor that turns a much larger gear that does the pulling..
you have to use small and large gears to increase power
Danny9 years ago
yes look at oodalumps's machine gun which is the same as u desciribed
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