Fixing our lift…

Help! Our lift does not lift up to its maximum height. Here are some photos of it and the gear ratio.

It will lift up just a little bit (like a couple of inches), and then it will just stop. The motors stop spinning and the lift just stays at the same height.

Why so many cantilevered gears?
And I don’t see any bearing blocks.
The friction must be killing it.

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We do not have the connectors for the metal 12 teeth gears…
And our lower gear ratio (3:5 torque) was not working well.

Try using a bigger gear ratio. You can look up compound gear ratios because that is what you need. You might want to put the gears inside of the frame (on the lift and drive) otherwise the gears might slip. Also please add some bearings and improve your build quality. It might be helpful to design your robot in CAD and then build it, otherwise it might be sketchy. I really hope this helps.

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Usually, if you are using more than 2-3 green gears on each side of your lift then you are likely wasting your precious time and energy. That is way too many gears, you should only be doing what is necessary.

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There may be alot of built up pressure/friction because the gears are on the outside without any other c-channel on the outside. It may also help if there were bearings blocks so that the axles are not rubbing against the c-channel.

Your motors probably don’t have the power to lift up all the way. As everyone else said, use bearings/pillow blocks and reduce how many gears you are using. Another tip though is to add some rubber bands so the lift can just pseudo float and there is less load on the motors. You can also try and use a different gear ratio (motor core).

I don’t think I see bearing flats on the gearbox as well.

You could just use infinite rubber bands

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But infinite rubber bands would just stop the lift from going down…? I mean I get that it was a joke, but that’s not how rubber bands work.

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Have you tried a 1:7 gear ratio with 1 or 2 100 RPM motors? Because that only uses one 12 tooth metal pinion and one high strength 84 tooth gear.

the perfect # of the rubber bands is when the lift stays in equilibrium without touching it

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‘Tis true
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If you wanted more torque you could simply use a red cartridge, it would help reduce the use of gears, externally.

Like everyone has said bearing flats, also washers to give clearance to the C-channels. I would go with the 12T high strength but if you dont have it use the other thin 12T looking one and put 2 together on the drive shaft

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