Weighing Empties & Testing

Scale Test Car

The General Foods track scale is weighing a bit heavy as an 80,000 lbs. Scale Test Car is positioned on John Parker's Fall River Division. Let's hope it proves to be within tolerance once the Track Mobile is uncoupled.

Weighing Empty Cars

Rail cars are weighed when built, and then every year or two, to determine their Light Weight. They are also weighed after repairs or painting. The Light Weight is stenciled on the car side.

To model this, your home road freight cars could cycle through your scale track every year or two. Of course, any new cars should be introduced to your railroad only after weighing. And any time you repair a car, you'll need to have your yard crew reweigh it.

The WeighStation™ Track Scale comes with Range "B" set for 40,000 to 50,000 lbs. — an appropriate empty range for rail cars of the 1950s. This can be adjusted to fit your railroad as explained in the Product Manual.

Testing with a Scale Test Car

Track scales are tested and certified annually. Scales have to be accurate to within 2/10s of 1% (0.002 times the true weight). Adjustments are made on the spot if the scale is not within this tolerance.

For example, an 80,000 lbs. Scale Test Car must produce a reading within 160 lbs. (0.002 times 80,000) of true weight, or within a range of 79,840 lbs. to 80,160 lbs. Since a typical scale displays to the nearest 100 lbs., 79,900 lbs. to 80,100 lbs. passes. Any other weight values fail.

Track scales are tested by weighing a Scale Test Car in four positions on the scale: extreme left end of scale, left of scale center, right of scale center, extreme right end of scale. All four weight readings must pass.

To model track scale testing and certification, your Scale Test Car should be delivered to each of your track scales annually. A specially trained crew runs through the testing as outlined. Take a failing track scale out of service until the next operating session, when it will be retested and (hopefully) certified.

The WeighStation™ Track Scale with its NightScope™ Infrared Detector installed at the midpoint of the track scale will give readings for the two center Scale Test Car positions. Instruct your Scale Test Car crew to take two readings, one left and one right of center, with the car slightly over the sensor for each reading. Both readings must be within tolerance for your scale to pass and be certified.

The Track Scale Digital Display model comes with Range "C" set for exactly 80,000 lbs. (This can be adjusted to match your Scale Test Car as explained in the Product Manual.) The Track Scale will slightly vary the displayed weight so that there will be an occasional out-of-tolerance weight when the maximum and minimum weight limits are set to the same value.