I built a lift table that uses 2 linear actuators controled by a store bought control box that uses 3 momentary switches that can be programmed for 3 stopping points My problem is one side is faster than the other. The system is 12 volts and each actuator pulls 3 to 5 amps. I thought if I install a potientiometer in line of the fast actuator I could adjust the voltage to one side to slow it down to match the other side. It takes about 40 seconds to go up or down so it is not a constant load. I can't seem to find a potentiometer that will handle the amperage any thoughts?

 

That's going to be a real trick, trying to sync the speeds of two DC motors over a long period with varying loads. You need one of two solutions. One is to add a tachometer to each motor and get two controllers that will use the tach to control the speeds. Still may not do it for you. The other is to change the motors to steppers, with one controller, driving both motors.

Ken