Trailer brakes weak, a few questions:

ajriding wrote:
3 amps or 3 volts? previous poster said this… Should not matter unless you suspect issue with wiring or controller. Brakes work off a 6 volt system, not 12. The max output for the controller is 6 volts. That should be 6 volts per brake, not 3 (amps get divided, but not volts here). Usually anything over 2 will operate the brake magnet then from there to 6 will increase the magnetism and increase the braking power.

I recently let trailer sit for a couple of months then the brakes were very, very weak at first. I had the controller set to max and still was not great breaking. 2 hrs drive and I could gradually lower the controller setting and the drive back I was back to normal with the controller set very low to get the power out of the brakes I wanted.
Maybe the drums rusted over and it took that long to wear it off and evacuate the debris from the inside of the drum? I don't know.

The trailer should at least be able to stop its own weight.

How long did / have you driven your trailer with unsatisfactory brakes?

Brake pads should be able to sit for 12 years and still work, though the steel parts might see some rust and need exercising or brake grease to move easily.

Easier to lock up one wheel on a tandem than on a single axle trailer. Easier still on gravel.
They need to be adjusted, as stated above, as the brake pads wear out and to keep all wheels performing at the same level. Typical drum brake adjustment rules apply. See any of the many instructional videos or post on topic.

6 volts? seriously? not on my trailer they don't nor any other ive had

brake magnets are in parallel and all see 12V at full power and 3 amps each(depending on size) for a total of 12 amps on a tandem trailer

the biggest issue with the electrical system for these brakes is voltage drop due to the high current draw. this is usually because of insufficient wire size and or bad connections.

all of the wire used has to be big enough, all the way from the tow vehicle battery to the brake controller, to the 7 pin connector and around the trailer. that's a lot of wire!