Subject:  Morris Park Electric Vehicle Project
Date: 1997-03-13 20:45

Report from Lee Hart for Thursday, March 13 1997:

I picked up a second farm cart from Fleet/Farm ($136.32) and delivered it
to Joe Rossow's class at Morris Park School. This was my second meeting
with the class, but they have not been idle. The students are really
excited about the project!

They watched the movie "Race the Sun", and the "Panther" project video on
how other groups built and raced this type of electric vehicle. This gave
them some pretty strong ideas on how they want theirs to look.

The class organized into 7 teams of about 4 students each. They drew up
plans, and built models with cardboard, soda straws, and duct tape. The
idea is a roughly triangular frame with two front wheels for steering and
one back wheel powered by the motor.

Drive System

The automotive fan motors we purchased have rather poor bearings. I talked
to an engineer at Sterling Instrument, who suggested a belt drive instead
of a friction wheel; it will put less load on the motor bearings, won't
slip, and is not sensitive to wet or dirty tires. I requested catalogs for
myself, Joe Rossow, and Rick Cash.

I found some surplus cogged pulleys and belts at ABC Electronics. I bought
4 pulleys and 2 belts ($6.40). Two of the pulleys are for 5/16" shaft and
fit the motors perfectly. The other two have a hole for a 1/4" shaft, but
could be drilled out. All four pulleys are 1" diameter with 16 teeth,
aluminum, with setscrews. The belts are short (fits around the pulleys if
their shafts are on 3.5" centers), but is an example to look at. Sterling
lists belts up to 100" long.

You could put a large pulley on the wheel, and a small one on the motor. Or
attach an empty bicycle rim to the spoked wheel, and use it as a pulley.
Joe's class wants to use a jackshaft with a chain to drive the back wheel,
and the belt drive from the motor to the jackshaft.

Rick; do you want a couple of these pulleys to play with?

Lee Hart