On my layout I have two freight yards that are serviced by SW7 switchers. Freight trains are pulled into the yards by PRR M1a locos and are broken down and made into new trains by the SW7's. But what could a real SW7 actually pull? Could they pull a fully laden 30 car train? Or more? Or just a few cars? This info would help in managing my yards realistically.
Thanks in advance....
Barry
Yes. On the flat, they could pull 30 cars. And more. And yards are flat. Except hump yards.
I look forward to hearing from railroaders more about the max load for a switcher. Certainly the change from plain to roller bearings had a huge effect. If yer running a steam loco in main line service, I expect there'd be a lot of plain bearings.
Cold weather will certainly take a bite, perhaps huge, out of what a switcher can move. But not too many modelers choose a cold blustery day to model. Yuk!
Ed
bsteel4065But what could a real SW7 actually pull? Could they pull a fully laden 30 car train? Or more? Or just a few cars? This info would help in managing my yards realistically.
Barry depends on the tonnage-normally 30-40 cars including loads and empties however,heavier tonnage trains would require two switchers even on the flat.
A 8,000-10,000 foot train would reqiure several cuts even when using two switchers.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
In the real world we regularly moved 90 or 100 car trains with a yard engine. I said moved. One certainly could not get out on the main and run with that kind of a load.
Conventional railroad wisdom was a yard engine should be able to handle any road train in the yard, whether pulling it back to switch it out or shoving it into a track upon making it up.
In the model railroad world, I try to apply the same pricipals but for HO scale about the only engines that come close for me are Kato NW-2's and Atlas S-2 ALCOs. The P2K EMD's are nice running engines but lack the traction to handle a 35 car train for me. Poor little HO scale switchman must walk down the yard track and make a cut when switching out a long inbound train.
I do find that as my car fleet grows with the better rolling later cars, the engines can pull more cars at a time.
Be happy in your work.
Charlie
Back when SP was SP, I saw an SW1500 pulling 45 cars going, uh, briskly past Albany Hill in El Cerrito, CA. Coulda been empties, I suppose. And certainly roller bearings.
I had the impression that the dispatcher had a REAL train on his tail, and he was anxious. Or maybe he had a lunchtime meeting.
I think a lot depends on the era you are modeling and the type of traffic your railroad is handling. Where I worked we received most of our Eastbound traffic in interchange from other roads and probably half the cars were empty. The only real heavy trains were things like the National Steel coil train that ran between Burns Harbor and Granite City, and a couple of ore trains that were run through jobs with no reall switching done to them.
From the 60's on the NYC and PRR at E St Louis, through Penn Central and eventually Conrail, I never saw yard engines MU'd. Every job used a single locomotive. I was there nearly 20 years and we made up and broke up a lot of 80-100 car trains around 5000 tons.
One other factor was the engineer. Some guys could get an engine to really pull and I knew one that couldn't get an engine to do much of anything. He was good for switching the caboose track and that was about all.
charlie9From the 60's on the NYC and PRR at E St Louis, through Penn Central and eventually Conrail, I never saw yard engines MU'd. Every job used a single locomotive. I was there nearly 20 years and we made up and broke up a lot of 80-100 car trains around 5000 tons.
NYC use either a single ALCO S-2(either 9633 or 9636) or a EMD SW7(usually 8919 or 8880) for yard switching at Mckinley Ave yard. However,transfer runs was handled with 2 SW7s usually numbers 8888/8889 while the NYC/N&W transfer run to N&W's Bannon Yard(on the South-East Side of Columbus) was handled by 2 GP7s because the transfer trains was empty coal hoppers to the N&W and coal loads for the NYC.
The only reason I remember those switchers numbers is I can't remember not seeing them in Columbus(Oh).Another engine I remember was a ALCO RS-3 #5345.
Hi everyone
Thanks for all the information. I should say I am amazed at the pulling power of yard switchers. I had thought that an SW7 would have had to break down a 50 car train to pull. But as you all say, a yard is on the flat, they're not required to pull a long train any distance and, let's admit it's what they are designed to do!
Thanks again for all your knowledge and for sharing it.
Best regards
In terms of low speed tractive effort the SW can probably pull more than the M1. In good conditions an SW has from 40,000 to 70,000 lbs of tractive effort available, similar to most heavy Mikes. It just won't move the train as fast because it runs out of horses.
Good stuff from charlie and Brakie. They've BTDT.
Something to keep in mind are that the newer sound versions of model SW locos often do not pull as well as the non-sound versions did. Once you make space for a speaker, that takes a big bite out of the typical weight inside. I've not any experience (my EMD switchers get narrowgauged into road locos ), but seen enough complaints from thos who've found out about this tradeoff.
Obviously, with newer, smaller speakers, this is less of an issue, but if you're doing your own sound install with sugarcube speakers, for instance, you may want to start with a non-sound SW unit and cut away only the space from the weight you need to preserve max tractive effort.
Mike Lehman
Urbana, IL