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DC motor with lots of vibration on shaft



I have a DC brushed motor[1] to which I’ve attached a disk and fixed to that 6 utility knife blades. I’m using it (on a sled) to cut strips of corrugated cardboard.

The problem I have is that it’s barely powerful enough, and after using it for a while black grease has leaked out some and it’s started to struggle to do the job. (It occasionally gets bound up in the cardboard.)

I’m considering using a Pololu 75:1 25D metal gear motor[2] with 130 oz·in of stall torque. It runs slower than my current motor but I’m hoping the higher torque (6x my current motor) will help it plow through the stock more easily. Does this sound like a good approach? (If so what kind of motor driver do I need? I’m assuming my current one[3] just doesn’t have enough amps.)

This is my first robot. Any advice is much appreciated!

[1] something very similar to this: makeblock.cc/dc-motor-25-6v-185rpm/
[2] pololu.com/product/1575
[3] pololu.com/product/2135


Hello, Drew.

I am not sure what motor might be appropriate in your situation. However, we do not recommend any of our products be used in situations where injury or property damage is a possibility. Mounting utility knife blades on a rotating disk certainly sounds dangerous, especially as a first robot.