#60 ~ A Little More.... Tonnage Ratings on the C&S
Posted by Mike Trent on Apr 01, 2016; 10:09pm
URL: http://c-sng-discussion-forum.254.s1.nabble.com/60-A-Little-More-Tonnage-Ratings-on-the-C-S-tp5040.html
To follow up a bit on the #60 thread earlier this week, which was pretty interesting, and the header photo above. I thought I'd share a little comparative data on the relative tonnage rating of #60, a Class B-4-C engine, to other classes.
On the timetable reference attached, pay attention to the listings for Como to Boreas, which is 4%, the ruling grade, the one that matters most.
You will see that the B-4-F Class (74-76) is rated at 145 tons, the B-4-E Class (71-73) at 120 tons, the B-3-C (4-10) and the B-4-D (63-70) Classes are both rated at 110 tons, and both the B-3-B (21-22) and the B-4-C (57-62) Classes are rated at 80 tons.
As an aside, you will note that the B-3-A class, (11-13), is rated at only 70 tons. I believe this is due to either a difference in the cylinders or some other reason after the engines were reboilered, or, it is simply a mistake, as at least #12 and #13 after reboilering appear to be exactly as #'s 21 and #22 and should have been classed as B-3-B. Prior to reboilering, these three engines were UPD&G Cooke Moguls, exactly as the DSP&P Moguls which were reboilered by the C&S starting in 1900 and became the B-3-C Class.
Bear in mind that the tonnage rating for a loaded 30 ft freight car is 25 tons, so with that number you can easily figure how many loaded cars could be handled by each class of engine. As a relevant example, #60, with a tonnage rating of 80 tons was only able to handle three loaded cars on a 4% grade. There are a lot of other calculations that figure into tonnage ratings, including actual weight of empty or lighter than actual capacity cars, and even a flange friction factor based on curvatures of a particular section of the railroad added to the grade. But for a purely simple (Tonnage for Dummies) rule of thumb, figure these numbers for the 4% ruling grade as how many loaded cars in your consist. Light weight (22000 lbs) is 11 tons on a boxcar. It was the responsibility of the Conductor to keep track of this stuff, and the total tonnage of the train determined how many helpers were needed. I've seen a photo posted here fairly recently of a six car train with a road engine and one helper working the grade up "N" Hill out of Breckenridge. That would be right, figuring that even a single Big Hog B-4-F Class was only rated at five loads and these were almost certainly loads of Concentrate from Climax.
Now you can easily imagine how it came to be that #60 and her sister engines were used as switching engines. Another rule of thumb, with the exception of the B-3-C's, is that the lower the number and class number, the older and smaller the locomotive.
Unless you are standing next to #9 and you actually see how fat that boiler is, or if you can see scale models of a B-3-C next to some of the other classes of engines, you would be surprised that it has a tonnage rating equal to a B-4-D or a C-19.
Regarding the tonnage of the passenger train, the old as-built Cooke Moguls were able to handle a Baggage/Mail and single Coach with no problem, so the rating of each car was probably about 30 tons, I would guess. That works, too, for the photo in the header of #60 carrying what was probably an empty boxcar picking up records and other items along the line for the last run in 1937. As mentioned above, the tonnage for that empty car was only 11 tons. A second coach making a three car train behind #60 might have been tense, but the B-3-C's could handle it easily.
Some of this is probably old hat to some of you, not so much for others, perhaps. But now you have some extra work to do, and you might have to consult the tonnage listings on your freight rosters to help figure out how many more engines you'll have to add to your motive power roster to handle your requirements.
Bob Stull's fantastic layout in Denver featured a 4% ruling grade. One night back in about 1986, I took my three B-4-F engines and #537 (also rated at 21,000 lbs/145 tons) and 10 freight cars. I had two engines doubleheaded at the front, one in the middle, and one just ahead of the caboose, just as the C&S would have. They had about all they could handle, so I figured that my engines and my weighted freight cars came out to just about the right ratio. It was quite a sight, I must say.
URL: http://c-sng-discussion-forum.254.s1.nabble.com/60-A-Little-More-Tonnage-Ratings-on-the-C-S-tp5040.html
To follow up a bit on the #60 thread earlier this week, which was pretty interesting, and the header photo above. I thought I'd share a little comparative data on the relative tonnage rating of #60, a Class B-4-C engine, to other classes.
On the timetable reference attached, pay attention to the listings for Como to Boreas, which is 4%, the ruling grade, the one that matters most.
You will see that the B-4-F Class (74-76) is rated at 145 tons, the B-4-E Class (71-73) at 120 tons, the B-3-C (4-10) and the B-4-D (63-70) Classes are both rated at 110 tons, and both the B-3-B (21-22) and the B-4-C (57-62) Classes are rated at 80 tons.
As an aside, you will note that the B-3-A class, (11-13), is rated at only 70 tons. I believe this is due to either a difference in the cylinders or some other reason after the engines were reboilered, or, it is simply a mistake, as at least #12 and #13 after reboilering appear to be exactly as #'s 21 and #22 and should have been classed as B-3-B. Prior to reboilering, these three engines were UPD&G Cooke Moguls, exactly as the DSP&P Moguls which were reboilered by the C&S starting in 1900 and became the B-3-C Class.
Bear in mind that the tonnage rating for a loaded 30 ft freight car is 25 tons, so with that number you can easily figure how many loaded cars could be handled by each class of engine. As a relevant example, #60, with a tonnage rating of 80 tons was only able to handle three loaded cars on a 4% grade. There are a lot of other calculations that figure into tonnage ratings, including actual weight of empty or lighter than actual capacity cars, and even a flange friction factor based on curvatures of a particular section of the railroad added to the grade. But for a purely simple (Tonnage for Dummies) rule of thumb, figure these numbers for the 4% ruling grade as how many loaded cars in your consist. Light weight (22000 lbs) is 11 tons on a boxcar. It was the responsibility of the Conductor to keep track of this stuff, and the total tonnage of the train determined how many helpers were needed. I've seen a photo posted here fairly recently of a six car train with a road engine and one helper working the grade up "N" Hill out of Breckenridge. That would be right, figuring that even a single Big Hog B-4-F Class was only rated at five loads and these were almost certainly loads of Concentrate from Climax.
Now you can easily imagine how it came to be that #60 and her sister engines were used as switching engines. Another rule of thumb, with the exception of the B-3-C's, is that the lower the number and class number, the older and smaller the locomotive.
Unless you are standing next to #9 and you actually see how fat that boiler is, or if you can see scale models of a B-3-C next to some of the other classes of engines, you would be surprised that it has a tonnage rating equal to a B-4-D or a C-19.
Regarding the tonnage of the passenger train, the old as-built Cooke Moguls were able to handle a Baggage/Mail and single Coach with no problem, so the rating of each car was probably about 30 tons, I would guess. That works, too, for the photo in the header of #60 carrying what was probably an empty boxcar picking up records and other items along the line for the last run in 1937. As mentioned above, the tonnage for that empty car was only 11 tons. A second coach making a three car train behind #60 might have been tense, but the B-3-C's could handle it easily.
Some of this is probably old hat to some of you, not so much for others, perhaps. But now you have some extra work to do, and you might have to consult the tonnage listings on your freight rosters to help figure out how many more engines you'll have to add to your motive power roster to handle your requirements.
Bob Stull's fantastic layout in Denver featured a 4% ruling grade. One night back in about 1986, I took my three B-4-F engines and #537 (also rated at 21,000 lbs/145 tons) and 10 freight cars. I had two engines doubleheaded at the front, one in the middle, and one just ahead of the caboose, just as the C&S would have. They had about all they could handle, so I figured that my engines and my weighted freight cars came out to just about the right ratio. It was quite a sight, I must say.
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