# Gear Lifts

Edit : Oops! The title should be gear ratios.

So my team and I are deciding on a scissor lift for our way of height. However, we’re all pretty new to robotics and we’re a bit dependent on the internet, as our teacher is busy doing other work. On top of being new to robotics, we have very little knowledge of physics and our high school doesn’t offer it (we’ll ask for next year, hopefully). We did take physics, but that was in elementary-middle school and most of what we learned has slipped our brains!

Now, my question is, how do we decide upon a gear ratio? How do we know if we should use a 7:1, 3:1, 2:1, etc.? We agree that we need a gear ratio that gives more torque, rather than speed.

On a side note, how do we quickly know how many teeth are on a gear rather than counting? (A bad question, I suppose - cannot ask teacher, it’s the weekend).

Plus the 1:3:5:7 roughly state how many holes the gears take up.

In terms of your scissor lift specifically it depends on how many motors are on the lift. The gear ratio multiplies the amount of torque so more motors still gives more torque.

In a very very simplified world 6 motors 1:1 is as strong as 2 motors geared 1:3 for torque. This doesn’t take into account friction differences so it isn’t a perfect explanation but it’s good enough for what you want.