Lessons learned

- Use support bars under clamper rails and cut out ALL the floor.
--Or use a servo to raise clampers - but how to lift all 8 clamps.

-Move Positioner farther away from Dumper and leave 1 car un-dumped - could not push it in correctly anyway. Dump the last car by pulling string of cars though from other end with a locomotive and stopping in the dumper.

-Positioner top rails act as a brake since the bottom rails are rolling the wheels.

Coal Load: 3/4 cup to fill 1 car
Perlite weighs 18 grams per 1/4 cup :54g = 1.9oz
Walnut shells weigh 22 grams per 1/4 cup :66g = 2.3 oz
Plastic aquarium gravel weigh 42 grams per 1/4 cup :too heavy
Sand weighs 78 grams per 1/4 cup :too heavy

Even after soaking in paint wash Perlite seems to break very easily.. too dusty?
Still crunching walnuts i bought at grocery store to get the shells.
10 grams = 0.351 oz
1 oz = 28.47 g