Above: The motor bracket is scratchbuilt out of .032" brass, and the rear axle bearings
are bits of 3/32" brass tubing - primitive! The motor and bracket are soldered together to form
the motor/bracket assembly.
The front axle tube is attached to the chassis only by the two pieces of .032" piano wire you
see running along the length of the chassis on either side of the motor. The front axle tube is not
soldered directly to the drop arm.
Those two pieces of piano wire are soldered to the main hinge pin (which runs the width of the chassis
under the lower front edge of the motor bracket). From the traditional standpoint, the front axle tube
and the .032" piano wire constitute the whole center section of the chassis!
All the rest is the motor/bracket assembly and the drop arm, hinged together. The crook shaped piece
of piano wire along the left edge of the chassis serves to "spring" the movement of the
drop arm relative to the motor/bracket assembly.
See
larger version of this image (78K).