I have some questions about scales and the weighing of cars. I’m modeling a shortline coal hauler in the 1950-56 era and so my questions pertain to that era technology. I know the loco would use the non-live rails of the scale but the other questions still have not been answered.
1.Would cars have to be weighed individually…uncoupled from any other cars?
2.Would cars be weighed while moving?
3.If so, what would be the maximum speed for weighing?
How long did it take to weigh a car?
How often would the scale have to be calibrated/verified using a scale test car?
Would the calibration be done by the railroad or did someone from the Bureau of Standards & Measurements have to do it?
There are several types of scales, those designed for single cars, those designed for weighing coupled cars, static scales and weigh in motion scales. All were available in the 1950’s. Static, uncoupled scales were probably the most common. Weigh in motion scales are almost always able to weigh cars coupled.
Maybe. Could be.
Probably about 5 mph.
Static, a minute a car or or less.
I think annually or every couple of years.
Calibration was done by the railroad, certification was done by a scale inspection bureau, such as the Eastern/Southern/Western Weighing and Inspection Bureau.
By the 1950’s they were starting to get sufficiently fast electronics / computers to weigh trains while they were moving though at a very slow speed like 2-3 MPH - at least at a few locations.
In the sixties bar codes (as now used on things you buy at the store) began to be used by some railroads like the DM&IR to allow automatic identification of the car by a scanner as it rolled over the scales and was weighed.
Actually, “Stix,” The Automatic Car Identification (ACI) system, with color-bar code labels applied to rolling stock for reading by computerized KarTrak scanners, was only introduced in 1967, and it wasn’t until 1970 that all equipment in interchange service on roads belonging to the Association of American Railroads (AAR) had to have ACI labels. Equipment used intraline did not have to be labeled, and often was not on railroads that did not themselves use the ACI system. The system didn’t last long, and the AAR abolished the requirement for ACI labels as of December 1977. On the other hand, by 1945, at least one scale company was advertising track scales with automatic weight recorders that could weigh four or five cars a minute. Happy New Year, Andy
1967-NYC Harrisburg Illinois. Just about all our business was coal. (400 to 500 outbound loads a day) When the loaded cars arrived from the mines, the yard clerk would make a list of them and write the tare weight of each car on the switch list next to the car initial and number. Then the clerk in the office would make out a blank weigh ticket for each car showing the car number and tare weight. These tickets were then lined up in the same order as the cars appeared on the switch list and as each car was cut off at the crest of the hump, it rolled across the scale which was just downhill a little ways from the top of the hill. As each car crossed the scale on it’s way into the classification tracks, the clerk would insert the scale ticket for that particular car into the scale printer and the gross weight would be embossed onto the ticket. Of course there were fumbles now and then when the clerk would have to holler over at the yardmaster and tell him to stop shoving the cut so he could get things straightened out. This usually meant that the yard job had to go down into the outbound yard and chase down the car or cars that missed weighing and start humping over from that point. That usually got the yard crew all upset since it interfered with their “early quit”. The conductor would often come into the office griping and bitching so we just all said that we were the one who screwed up so he would be a little bit mad at everyone instead of real angry with just one guy. Bunch of cry babies.
Railroads found it convenient to put car scales (that could weigh cars on the move) on the upward grade leading to a humpyard.
Certain cars needn’t be weighed such as circus cars and stock cars (carrying animals) and those carrying vehicles. What other loads weren’t charged by weight and so needn’t be weighed?
many shippers had weight agreements with the railroads through the western or eastern weighing and inspection bureau. (wwib or ewib) since they loaded a known quantity of a given commodity in the car and knew the unit weights, railroad companies took their word for the net weight. this is especially the case with volume shippers of things like canned goods or auto parts. years ago when i was a claims inspector, the local inhabitants in E St Louis stole a bunch of bagged sugar out of a car coming to us from a western road while it sat on the connection. i had the car reweighed and found it still had over 10,000 lbs more in it than the billing showed. of course, i had to call the customer and tell them that someone had broken into their load an put an extra 5 tons of sugar in the car. this shows that not all shippers were accurate (honest?) about their declared weights.
tank cars were often moved without weighing since the shipper knew how many gallons of a petroleum product or chemical they had pumped into the car and could calculate the weight from the known specific gravity of the product.