Motor gearset for DR4B

Our team uses 2 V5 motors with 100RPM gearset together with 7:1 gear ratio to move DR4B up and down. The DR4B arms do move, at rather slow motions. There are many other DR4B robots on youtube that move at much faster pace. They all seem to use 7:1 gear ratio. maybe they use 200RPM gearset. Theoretically, that cuts torque by half. Just curious how do they have enough power to move the DR4B up and down with the claw and all the cubes. To be clear, we use rubber bands to counter-balance the weight. But the motors have to overcome the rubber bands’ elasticity doing down.

My team’s dr4b uses 15:1 and 100rpm motors

Can you post some pictures of the lift.

It all depends on your lift. Experiment.

How do you get 1:15 ratio?

wouldn’t that be painfully slow?

Use compound gears 5:1 from the motor and 3:1 to the arms. The speed is slower yes but we still are fast enough to get stacks and it makes us more stable raising and lowering.

I use a 1:35
I use 1 motor though

Dude, that’s insanely slow. How many cubes are you holding?

1 or 2. It’s just for towers. I’ll probably change the gearing later on

Yeah, holy crap, 1 motor 1:7 should be more than enough for 2 cubes. Do you have rubber banding on your lift?

Problem is, I kinda dont have enough 84 tooth gears

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What. How do you get that insane ratio

This means you at least have 1 84 tooth gear, and they come in packs of 4. What are you using the others on? Also, if need be, you could use the thin 84 tooth gears.

I’m using 2 in my tilter. I only have 2 left, which isnt enough for my lift.
I also dont trust the thin gears enough to use them. Let’s just say I had bad experiences with them


1;7 then 1:5
20 charrrrs

This probably means you sandwich the c-channel, but you could always just attach 1 gear to the side of it.

Doubling them up is a great way to ensure they won’t snap. Especially if you used them on the tilter which is stationary on the robot.

How do you get 1/7 if you don’t have 84t gear

The high strength gears have bigger teeth which makes them HS (I think). Doubling up with LS would prevent snapping, but I don’t think it’ll be the same as an actual HS gear.

I don’t have 4 hs 84 tooth gears, so I could only use 1