I have developed an interest in: B units, calves, and slugs. Is there an interest in this area. Has anyone published on this topic. I would be interested in learning more. Thanks in advance.
I haven’t seen anything (as far as books or special magazine issues devoted to the units mentioned) in print or on the internet, but a Google or Bing search could possibly help you find information, though you may have to go to multiple sites and do multiple searches.
I remember an old issue (I think it was in the late 1980’s) of Model Railroader I got from a train show a few months back had an article on how to model Seaboard Mother and MATES units. The MATES units are essentially engineless B-units for the (then) modern locomotives.
Also, in the October 2009 issue of RMC, there’s an article on building a CSX slug. Again, the CSX slug units are engineless units conected to a unit designated as a Mother for the unit, to provide tractive effort. The main differance is that, unlike the MATES program, the Slugs are EMD units given a seccond lease on life, and look in almost every way like a normal locomotive, untill you get close to see that the engine acess doors have all been removed, and that the radiator screens and fans have been plated over. A mojority of the Slug units kept their dynamic brakes, though, and all kept their cabs. How it worked is that the Slug unit would be at the head of the train, with it’s Mother unit connected immidiately behind it,providing power. The Slug, which still has MU capability, controlls all of the locomotives in the head end of the consist. One thing that the crews of the Slug units were happy with was that, without the diesel engine right behind the cab, they could enjoy a quieter ride.
On the corprate side, the Slug and MATES program both offered exeptional fuel savings, as one EMD engine was powerful enough to give the Slug and MATES program locomotives (as well as the Slug and MATES units themselves) the power of 2 locomotives.
I hope I sort of answered your question. As mentioned, Both the Slug and MATES programs were not accual locomo
I know of no references but in general a B unit is simply a locomotive without a cab intended to be a booster. They have a prime mover and traction motors. Some of them had a simple control panel to move them around the loco shops.
I have only ever heard the term “calf” used for a B unit of an EMD NW or SW type locomotive.
A slug is a totally different animal. It has only traction motors powered by the prime mover of the locomotive it is attached to. A single locomotive generates much more power than it can use while moving slowly around a yard. That extra electricity is run through wires and used in the traction motors of the slug giving it greater power. Great for yard work. The first place I ever saw one was on the hump yard in North Platte.
I think the UP had more different types of “B” units than probably any other road. However the last locomotive I saw in the Santa Fe “book end” paint scheme was an SD45B right here in Denver.
Which locomotive types and their quantities were those, Tex?
Mark
http://en.wikipedia.org/wiki/B_unit
http://en.wikipedia.org/wiki/Cow-calf
I have to disagree with you on the underlined parts about. Many slugs don’t have a cab on them. They are there to provide extra traction and usually have been fabricated especially for that job. More recently, they have taken older locomotives and turned them into slugs because it saves drastically on building costs, as you descibe. Also Many slugs these days house the electronics for Remote control Units. The Hump yard here in Houston uses a slug set up between two SD-40-2’s and are remotely controled by the hump yard tower. I believe a similar setup is also used in the Bailey yard in North Platte Nebraska. Below is some sample pictures found on Railpictures.net of slugs.
http://www.railpictures.net/viewphoto.php?id=212618&nseq=5
http://www.railpictures.net/viewphoto.php?id=268773&nseq=7
I’ve heard of “calf”, as well as “daughter” applied to the GeeP cut downs that are/were at Avon Yard. Typicall, the pairing is wither Cow-Calf, Mother-Daughter, or Mother-Slug. Which is different from a B unit, in that a B unit has a full motor.
The Claf units take power off the mother unit. Usually, under 25-30mph, the mother engine creatwes more electriity than it needs, so, It puts the power into the calf unit for more horses at slow speed. Kind-of reversed to why we put more pickup shoes on a model train. Past the thrity, the mother needs more of the juice, and the calf is useless.
Beacuse of the speeds, Calfs tend to stay in the yards, but I have seen them on long, slow switching runs and for mountain climbing, and any railroad hat needs power without fuel, and does not surpass the 30mph speed limit (class 3, some class 2)
Another uncommon one to add t your collection, is the SP break sled. These didn’t even have the traction motors, just another set of brakes and deadweight to keep engines and unwanted parts of the train from going over the hump yard.
I first read about it in my historical diesel locomotive guide, but the Wiki link posted above also mentions the EMD TR3, which was a Cow-Calf-Calf lashup (called in the diesel guide as a ‘herd’). Wiki states only 2 sets were made, which jives with the spotter’s guide.
No, you are describing a slug which has electric motors but no engine or electric generator.
A calf had engine, generator, and motors but was cabless. The cow and calf came semi-permanently coupled with a drawbar, with the cow having the cab and engine controls. They were in the “TR” series of EMD diesels where the cab was on the inside end of the cow unit. The Southern Pacific had four cow-and-calf TR6 sets (originally numbered 4600-4700 … 4603-4703), each having a total of 1600 horsepower spread over 8 axles. The SP originally considered them roadswitchers to be used where track and bridges wouldn’t hold up to heavier units.
Mark
My favorite “B” units: Southern Pacific Baldwin AS-616 roadswitchers in tiger-stripe livery:
Mark
Most slugs were used in hump yard service where a lot of tractive effort and not much speed was needed. The original bodywork, prime mover and most other equipment was removed and replaced with concrete for weight. The result was a low bodied thing - can’t call it a locomotive, that had a slug-like appearance compared to the powered unit it was connected with.
In the late 70s, some railroads experimented with slugs connected to road locomotives. Boston & Maine built slug 100 from a GP9 which, I believe, they bought as a scrapper from SP. It was connected to Non-dynamic GP40-2s BM 300 and 301, and was a New England railfan favorite referred to as the Slug Set. They ran for some time in the original blue, then were repainted in Guilford gray scheme in the early 80s.
I modeled slug 100 from a dummy Athearn GP9
and the Slug Set using Athearn GP-40-2s with added details
Well lets see. Pulling out my non-existent UP reference (UP is one of my least favorite roads). What is interesting to note that there are ZERO FTBs. The UP was a coal hold out and missed the first generation of diesel power for freighters. Also interesting is the lack of B units for the 2nd generation stuff. Unlike the Santa Fe that had B units all the way to the end with the GP60B.
M-1000xB qty 1 each
C855B qty 1
F3B - 31?
F7B - 76? these F3s and F7s were renumbered more often than rabbits breed
F9B - 43
TR5B - 8
GP7B ? qty <9
GP9B qty
GP20B (Omaha GP20s) - qty 9?
GP30B - qty 40!
SD24B - qty 45!
DD35B - qty - 25!
GE #750 - qty 2
Erie 700 - qty 5
Erie 900 - qty 5 (actually the same 5 rebuilt)
Erie built 50-M-3B qty 3?
E2B - qty 4
E6B - qty 2
E7B - qty 7? so many re-numberings of these E units.
E8B - qty 28
E9B - qty 25
Alco PB1 - qty 4