"Tom Watson" wrote in message We race on a forty foot
Piantedosi wood track, with a starting pin
height of about 45", and the slope runs out flat at about 12' on a
level line from the pins. The pin to finish line distance is about
35' measured on the track.

We use tungsten weights that come in 3/8" d. cylinders and we drill
the car body out, starting on the centerline of the car and running
parallel to the centerline for one row on either side of it. The
drilled holes have about 1/8" between each and they are drilled to
depth with a forstner bit on the drill press.

We insert the weights into the center line of holes and attempt to get
the car to five ounces, with one ounce riding on the front axles. We
set the weights to be flush with the bottom of the car.

We straighten the axles in a press and hammer the nail head into the
press so that it is square to the shaft, and then file off the webbing
below the nail head. Then we lightly file the underside of the nail
head into a coned shape.

Then we insert the axle into the drill press and polish it with
wet-or-dry abrasive, starting at 600 grit and moving through the grits
to a finish with 1 micron polishing cloth. We wipe them down with
alcohol and put them in a baggie with a powdered graphite/moly
lubricant. We treat the underside of the nail head the same as we do
the shaft.

We use a jig on the drill press to bring the wheels into round and
then treat the tread with the same regimen of abrasives. We cone the
bore of the wheels and we polish with the same set of abrasives. We
use the same abrasives on the area of the wheel that contacts the
underside of the axle. We polish the inside edge of the wheels with
the same abrasives and then we take a rag and push graphite/moly into
the surfaces of the coned hub, flat face, treads, etc. We use a piece
of drill rod and some liquid abrasive to polish the interior of the
bore. Then we clean out the wheels with compressed air, then swab
with denatured. Then we put the wheels in a baggie that has some
graphite/moly in it and shake them up, then let them sit overnight -
they come out a cool looking graphite gray and - we hope - the
graphite gets into some of the crans and nookies.

We drill holes in the body at the bottoms of the axle slots, so that
the axles will go in straight. We load the wheel hubs up with
graphite/moly and push the axles through, trying to keep as much
lubricant in the bore as we can. We push the axles into the body
until the wheel bores are 1/32" away from the body. Then we spin the
wheels for a bit using the air compressor to direct a stream of air
over the wheel to make it spin.

Then we set the car on a piece of plywood that is eight feet long and
set to a five degree slope, being level side to side. We put a dot on
the twelve o clock position of the axle head and we turn each axle a
quarter turn at a time until the car can run a straight line over
eight feet.

We then run the air compressor over each wheel until we think the lube
is gone and test the car for straight again. A little more tweaking
to make it straight. Then we pack it with lube and we're ready to
race.

The boy ran third out of fifty his first year and second last year.
Then he went to the Districts and ran third out of 150.

To answer your question - I think that you have a friction problem, or
an alignment problem, rather than a weight problem.

I'd pay a lot of attention to the alignment.


Wheel balancing! And Wheel bearings . . . and machined axles. And,
synthetic bearing lubricants. Tried a taller gear ratio?
~)))))
NuWave Dave in Houston