# Building Differential

Does someone have a detailed guide on how I would be able to build a Differential.
I am trying to build a differential between 4 motors and a 6 bar lift but I can’t figure out how I would make one from the resources I have found. All the post I look at have only given me what a Differential is supposed to do but not an in depth look into how to build one.

These are the post I have already looked at:
Differential transmission - power takeoff from the drivetrain motors
passive Transmission
Vex Differential Guide

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If you are looking for a step-by-step guide, you most likely aren’t going to find one. The information from the posts you linked should be enough to guide you- they have renders that show how it works in detail.

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Even though it is an old video, this video explains differentials very well, it was my first real exposure to it, and I was able to build them after watching it. https://www.youtube.com/watch?v=yYAw79386WI
This is also great https://www.youtube.com/watch?v=nC6fsNXdcMQ&t=1s

If you are looking to use the power of 4 motors from drivetrain to assist lifting of the robot at the end of the game you will, probably, be better off using pneumatics to shift the power from drivetrain to some sort of a winch.

Differentials only made sense in the seasons when game rules had “motor penalty” and it would cost you two motors (out of 8) if you decided to add pneumatics to the robot.

But, if you like the challenge of mechanical complexity that will demand adhering to the strict best building practices just to limit your friction losses, and additional programming headaches for the sake of learning how to do it then, please, tell us more details about what you want to build.

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Not the right type of differential he is looking at- we can use the same principals in a differential like that, but in a different way.

This is very false. Power sharing mechanisms make sense in almost every game for VRC.

This is true. A differential as a power sharing mechanism is not very efficient, and a PTO or equivalent system would make sense in this circumstance.

From my experience, differential drive like Sylvie’s or mine have a limited range of motion, and this is not ideal for a winch.

I would recommend looking at PTOs, and asking in discords for examples of them. PTOs can have unlimited range of motion, as well as having the added benefit is less power lost to friction.

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I would do PTOs but my club does not have them. Maybe could get them if we get funding. I think just to make my brain hurt less il use a 4 motor drive train allowing for 2 motors for the lift and 2 motors for the other systems.

Doesn’t have whom? PTO isn’t a thing, it’s “Power Take-Off” concept. And you don’t need no pistons[*] to make this work. Ratchets, Rockers, or dedicating a small motor could turn the concept into reality:

*

No pistons, no cylinders, no leeks, no problems!

We you, @kmmohn!

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