Ignoramus32423 fired this volley in
:

The good news is that, as they run, even after a while, the heatsink
is only barely warm.

What you did not say was 1) the raw battery voltage, 2) the current (both
peak and average) for the arm 3) the current(ibid) for the tracks.

Like Jim said, at only a few watts, nothing's in particular danger here.

A star washer works ALMOST as well as a Bellville spring, so long as you
don't torque it down flat.

Lloyd