Engine break-in?

[erickkr]

I've read in several of the posts, mention of engine break-in. I know I have to break in my gas engines, but didn't think that electrics required a break-in period. Do they? And if so, what kind of rig do you set up to do it, and what type of runin do you do?? I don't want to stress my motors more than necessary
Ken :confused:

[jimwalker]

The only thing that needs breaking in on electrics are the brushes. They are square on new motor and don't fully contact the commutator. After sufficient run time they wear down to a curved shape which fully contacts the spinning commutator.

Until this break in period is complete, there is much arcing which pits the brushes and commutator. Standard practice is to run your motor from a single 1.5v drycell until it is dead. This gives the brushes a chance to form to the commutator without the arcing that occurs at full voltage runs. This gentle breaking in increases the brush and commutator life and probably increases the effeciency and power a few percentage points.

Jim