Trailer Brakes - How hot is TOO hot?

There is a problem with that burnishing process. New brakes have very little stopping power, so brake controllers are turned up to compensate. That might get braking near normal, but the magnet will be at maximum power tearing into the armature surface before it has mated to the magnet. That gouging will continue so magnet and brake drum life will be shorter. The resulting grooved surface will not allow the magnet to swing properly and further compromise braking. I now actually turn down the controller for awhile after replacing or reconditioning parts. I know, not a great idea, but this junk isn't ready for prime time.