RC Tank Warfare community hobby forum

I have a toy grade tank (4.8v) that is way too fast, I was thinking to slow it down with variable resistor or potentiometer on the motor wires, my question is, how? The tank has forward and reverse so would I need a pot on both - and + or just one of them, or another way?

You would need a variable resistor for each motor. And you would have to balance them so you went straight.
You'd probably only need pots that are 0 to 10 or 0 to 20 ohms.

Just one pot per motor on either black or red wires (+ or -).

As this will restrict the current to the motors, you will lose some motor torque, but not drastically.

There are other ways to do it, but I think they aren't so simple as the motors are bi-directional.

I'm not sure if you can get small enough pots at a high enough wattage, otherwise the pots could get quite hot. Unfortunately, I'm not sure if wire wound ones are that small.

As it's only 4.8 volts, wire wound may be overkill, but it wouldn't hurt to get as high a wattage as you can for small pots.

Never thought of those things, thanks.

Son of a gun-ner wrote:You would need a variable resistor for each motor. And you would have to balance them so you went straight.

As this will restrict the current to the motors, you will lose some motor torque, but not drastically.

If you buy the two pots at the same time from the same manufacturer, and set them at the same amount of turn, it shouldn't take that much to balance them.

It could be done with a pair of normal resistors (non variable) and a single high ohmage pot between the two as a trim for balancing any manufacturing difference etc in the resistors. Only problem with that would be needing to know the current draw of the motors and how much the motors would need restricting for a desired speed to work out their value.

And, like I said, you shouldn't lose much torque.

Have fun tinkering.

I've decided to try a PWM Speed Controller, I'm hoping that this will do the same but without losing torque.

Son of a gun-ner wrote:If you buy the two pots at the same time from the same manufacturer, and set them at the same amount of turn, it shouldn't take that much to balance them.

It could be done with a pair of normal resistors (non variable) and a single high ohmage pot between the two as a trim for balancing any manufacturing difference etc in the resistors. Only problem with that would be needing to know the current draw of the motors and how much the motors would need restricting for a desired speed to work out their value.

And, like I said, you shouldn't lose much torque.

Have fun tinkering.

Good idea, I hope it fits in ok

Probably cheaper than getting the individual components too