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"Front" of "B" units

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Posted by ATLANTIC CENTRAL on Sunday, April 26, 2009 11:03 AM

SSW9389

Santa Fe had 320 FT units. The first two AB pairs were built with drawbars. The next 316 Santa Fe units were built WITH couplers. Other railroads had FTs built with couplers, following the Santa Fe pioneered design. Preston Cook sent me the EMD drawings on some of these. Larry Brasher has documented this in his book on Santa Fe locomotive development.

Yes this is true, and, the Southern, Missouri Pacific and D&RG also ordered their FT's with couplers although not in the kind of quanitites as the ATSF. In the earlist days these where actually called FS rather than FT, the S standing for "separable", this designation was soon dropped or fogotten.

While the ATSF did buy a lot of FT's (FS's?), still, about two thirds of the total production where draw bar connected sets when built. And draw bar connected was the catalog standard for the product, with the extra couplers being an option.

Since the building block concept of the multi unit diesel was just comming of age, many at EMD and the railroads still thought in steam terms. The 2700 HP of an FT AB was seen as equal to a heavy 2-8-0 or a 2-8-2, so the need for smaller units of power was NOT imediately understood. Maintenence needs and load matching for efficency soon cleared that up.

Sheldon

 

    

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Posted by SSW9389 on Sunday, April 26, 2009 5:45 AM

Santa Fe had 320 FT units. The first two AB pairs were built with drawbars. The next 316 Santa Fe units were built WITH couplers. Other railroads had FTs built with couplers, following the Santa Fe pioneered design. Preston Cook sent me the EMD drawings on some of these. Larry Brasher has documented this in his book on Santa Fe locomotive development.

 

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Posted by trainsBuddy on Friday, April 24, 2009 11:53 PM

ATLANTIC CENTRAL

I assume you are refering to the DCC versions and their decoder settings?

Yes, I'm talking about DCC, why is there a different way of running trains?. Just kidding Tongue I figured that they didn't bother programming them differently.

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Posted by Anonymous on Friday, April 24, 2009 9:18 PM

Texas Zepher

MILW-RODR
A good example I just realized is the ad >>>> right over there for Standard Hobby Supply. Pair of BNSF (Dash 9's or AC4400's?) paired up long hood to long hood.

???? The question isn't about general MUing but about cabless "B" units.   I was not aware that there were any "B" dash-9s or AC4400s.  The last modern loco I saw that had a "B" variation was the GP60.

 There weren't.

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Posted by ATLANTIC CENTRAL on Friday, April 24, 2009 9:13 PM

trainsBuddy

What's interesting is that Walthers sets forward direction on their Proto 2000 B units to move towards the "F" location. But I have seen now quite a few pictures of GN prototypes where AB sets are running back to back - you can easily see that their fuel tanks point in opposite directions.

I assume you are refering to the DCC versions and their decoder settings? The manufacturer is not likely to set them differently for A or B units but simply leaves them at the default setting from the decoder manufacturer. since the models are wired the same, the front is the front, A or B, until you program them to run together as a consist.

With, DC all units wired the same will run in the same direction, regardless of front or back.

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Posted by trainsBuddy on Friday, April 24, 2009 7:38 PM

What's interesting is that Walthers sets forward direction on their Proto 2000 B units to move towards the "F" location. But I have seen now quite a few pictures of GN prototypes where AB sets are running back to back - you can easily see that their fuel tanks point in opposite directions.

I have a question about the number boards on F7A units. Does anyone know what color was the backlight on Great Northern diesels? Walthers ships them in white, just like headlight, but I've seen a person painting number board lights yellow.

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Posted by ATLANTIC CENTRAL on Friday, April 24, 2009 1:14 PM

R. T. POTEET

I was going to bring up about the FT's B-Units not being symetrical which would have definitely prescribed the way it was mated to it's A-Unit--I am equally certain that someone will have a photograph of an FTB coupled-up in a loco lashup at least in a manner which I would consider to be "backwards."

As has been pointed out, FT's where built as draw bar connected AB sets, back to back, as has been explained by myself and others. ABBA FT sets had couplers between the two B units, on the long end or front of each B unit.

Later, many railroads fitted their FT's all with couplers eliminating the drawbar connected AB sets, this would obviously then allow any position or arrangement.

ABA FT sets, as explained already where completely drawbar connected and used the FTSB B unit which was shorter and symetrical. Those too where often later fitted with couplers allowing any type of placement.

R. T. POTEET

This "BLOWHARD" OPINION is tendered in an attempt to HORNSWOGGLE the forum readership with prodigous quantities of completely INANE and absolutely MEANINGLESS INFORMATION: if I cannot dazzle with brilliance I will attempt to baffle with BS.

???????????????????????????????????????????????????????????????????????????????

The answers to this question topic are highly dictated by when you are talking about - when these locos where relatively new OR when they had been in service for years/decades.

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Posted by R. T. POTEET on Friday, April 24, 2009 11:28 AM

dehusman

grizlump9
 while we are on the subject of "B" units, didn't some of the covered wagons have a hostler control station inside so they could be moved about independently?

Yes, they did.

I was going to bring up about the FT's B-Units not being symetrical which would have definitely prescribed the way it was mated to it's A-Unit--I am equally certain that someone will have a photograph of an FTB coupled-up in a loco lashup at least in a manner which I would consider to be "backwards."

One of the hobby magazines--MR  I believe--had a photograph of one of these B-Units with a hostler hanging his head out of a window. I am certain that this would have been designated as the "front" of the unit but whether that would have mandated any specific coupling to an A-Unit I do not know.

This "BLOWHARD" OPINION is tendered in an attempt to HORNSWOGGLE the forum readership with prodigous quantities of completely INANE and absolutely MEANINGLESS INFORMATION: if I cannot dazzle with brilliance I will attempt to baffle with BS.

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Posted by wjstix on Friday, April 24, 2009 10:08 AM

GRAMRR

I have plans to couple my A-B and A-A sets with a drawbar, thinking that they'll look better coupled closer together, and shouldn't give me any grief operationally.  What do ya think?

That's what I do. I find like with Stewart FT's they can be very close together using their drawbar, and yet take curves fine. I put a Walthers paper diaphragms on one of the engines, they're too close together to use/need two. With other F's I make drawbars from styrene.

I believe laws/regulations require all engines to have an "F" to mark the front of the engine. On a B unit connected by a drawbar to an A unit, it would be considered one engine so only the A unit would have to have an "F" on it, but if a B unit has a separate no. and couplers on both ends, I'd assume it would need an "F" too marking the front...not that it would necessarily run with the "F" being in front, but it would be a way to tell which end is which.

One factor on how a railroad would set up an A-B set is that going back to the FT's, passenger F's with a steam generator had the boiler in the space in the B unit where the cab would have been if it had been an A unit. By putting the engines 'back to back' the steam generator would be closest to the first passenger car, which might be an advantage as far as running steam lines back to the cars.

With an A-B-A set it wouldn't matter, as the B unit would be going forward as often as backwards. BTW the FTSB (FT Short Booster) that was used for A-B-A FT sets ordered by railroads, was symmetrical so didn't have the overhang the regular FT B units had...and they couldn't have a steam generator because they didn't have the room because they were also shorter than normal FT B's.

Stix
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Posted by bogp40 on Friday, April 24, 2009 7:17 AM

Atlanticcwntral has pretty much described any orientaion  needed for a FB.

Although in any other use other than passenger where the steam generator/ water tank split between units, the B unit could be run in any direction.

B&O F3/7 passenger sets w/ steam generator required that the Bunit be positioned for steam gen coupling. These AB sets were ordered w/ steam gen in one ond water tank in other. Even some AA pass sets were done this way. The AA ran back to back though.

The front of the B unit is described by atlanticcentral, the blank section of the roof is toward the ft with fans to the rear. The dymamic fan or blanked plate (non dynamic) is to the front of the fans. These are the easiest stotting features to ditingish the orientation of the unit.  Of course there are many other features as the door placement, hatches, grills etc. but the rooftop is what stands out the most.

Modeling B&O- Chessie  Bob K.  www.ssmrc.org

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Posted by ATLANTIC CENTRAL on Friday, April 24, 2009 7:13 AM

In any three unit lash up (ABA or ABB) one unit will obviously be different from the other two. In the case of an ABA, one AB is always back to back. Which way it is pulling the train has no bearing because the whole point of having A units on each end is to make the set bidirectional so it does not need to be turned.

Many roads, like the NP used their F units for pssenger. It would have made sense to put steam generator equiped B units back to back. ATSF only had steam generators or their B units, do to the greater water capacity, so in a ABBA unit set in those cases, they may have prefered the B units back to back, again, placing the steam generators near each other.

Sheldon

 

    

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Posted by ericsp on Friday, April 24, 2009 2:50 AM

ATLANTIC CENTRAL

BRAKIE

dehusman

BRAKIE
So,some roads place a "F" on the front end of the "B" unit.

 

By Federal law ALL locomotives in the US have to have a F on the front end.

 

I don't think that was required on "B" units..

http://www.railpictures.net/viewphoto.php?id=168417&nseq=0

http://www.railpictures.net/viewphoto.php?id=264916&nseq=2

http://www.railpictures.net/viewphoto.php?id=182241&nseq=8

http://www.railpictures.net/viewphoto.php?id=88731&nseq=18

 

Larry,

The first two pictures you linked to have a "F" on the end to your left, that is the front. And in my experiance many B units where so labeled.

Sheldon

 

All of those locomotives have their front end away from the camera, which makes the F difficult to see. The NS unit actually has a yellow F on the white stripe, just to the left of the second grab iron from the left end. I am sure each ATSF unit has an F on it, but I cannot find them.

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Posted by alcodave on Friday, April 24, 2009 1:03 AM

Off Topic,but on the Norfolk and Western the F was almost always on the opposite end from the cab. Unlike most Railroads they ran them the RIGHT way!

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Posted by pall on Friday, April 24, 2009 12:50 AM

Interesting question, so I got all my books out on the D&RGW and found some photos taken by the EMD photographer. and it appears the ABBA sets delivered to the Grande, the b's are back to back which means the A and B of each end were facing the same direction. 

Paul         

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Posted by Texas Zepher on Thursday, April 23, 2009 11:31 PM

DigitalGriffin
I usually see them coupled in photos as front-back.

Hmmm, interesting observation but exactly opposite of mine.   The only "factory" photo I can find of a front-back configuration is of the EMD shot of the first Santa Fe passenger F7s. They were delivered as ABBA #s31 through 49.  Santa Fe designation is LABC.  The difference is that these were not permanently coupled each unit had normal couplers.

The only railroad that I know that consistently ran the "B" units in a forward direction is the NP.  Once again this doesn't count the FTs and early permanently coupled F3 units.  They are (at least all the pictures I can find and properly interpret) back-back.

I did look up some ABA combinations.  The Santa Fe Alco P set #51 had the B unit back to back with the first A and then the last A in reverse.  Technically then two of the three units were running backward.

The GN was really big with the semi-permanently coupled ABA sets.  But amazingly of all the photos I have, none pictures are "as delivered" factory shots.  I did find a picture where the B is running in the forward direction (on the point of the Western Star).

The bottom line for a modeler remains to do research on the specific prototypical road and time period.

As Sheldon implies, the later in time one gets the more loosey goosey one can get with the configurations.  The Santa Fe for one reconfigured/renumbered the entire F unit fleet at least three times. 

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Posted by ATLANTIC CENTRAL on Thursday, April 23, 2009 6:55 PM

BRAKIE

dehusman

BRAKIE
So,some roads place a "F" on the front end of the "B" unit.

 

By Federal law ALL locomotives in the US have to have a F on the front end.

 

I don't think that was required on "B" units..

http://www.railpictures.net/viewphoto.php?id=168417&nseq=0

http://www.railpictures.net/viewphoto.php?id=264916&nseq=2

http://www.railpictures.net/viewphoto.php?id=182241&nseq=8

http://www.railpictures.net/viewphoto.php?id=88731&nseq=18

 

Larry,

The first two pictures you linked to have a "F" on the end to your left, that is the front. And in my experiance many B units where so labeled.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Thursday, April 23, 2009 6:52 PM

OK, with or without hostler controls, B units of cab type diesels do have a front and back.

In the case of all EMD F or E units, the end with the steam generator (or the space it would be in on F units not so equiped) is the rear. A and B units are layed internally the same starting at the rear. The B units simply don't have a cab at the other end. The prime mover (diesel engine) is not in the middle, but offset to the rear. So looking a the roof of any F or E unit, the fans are closer to one end than the other. The end they are closer to is the rear. EMD FB units with steam generators used some of the "empty" cab space up front for additional water tanks.

EMD encourged railroads to run them "back to back" for a number of reasons. In an AB set, if you had hostler controls, that did in effect give you control at both ends since the B unit hostler controls are just inside the "front" door.

Also, on E units or if your F units had steam generators, they would be near each other and would work more effiecently and made them easier to operate.

ALCO PA/PB units did not follow this design. Instead the steam generator on the PB was at the front, in place of the cab. So many roads prefered to run the both forward, again because this placed the steam heat equipment together. The steam generators did require some attention by the crew, so having them together was a good idea.

Most of this applies to the earliest use of these locomotives when they where generally thought of as "sets". As railroads interchanged the pieces of orginal "sets" of locomotives these "rules" may or may not have been followed, subject to a lot of different conditions on each road.

Sheldon

    

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Posted by BRAKIE on Thursday, April 23, 2009 6:05 PM

dehusman

BRAKIE
So,some roads place a "F" on the front end of the "B" unit.

 

By Federal law ALL locomotives in the US have to have a F on the front end.

 

I don't think that was required on "B" units..

http://www.railpictures.net/viewphoto.php?id=168417&nseq=0

http://www.railpictures.net/viewphoto.php?id=264916&nseq=2

http://www.railpictures.net/viewphoto.php?id=182241&nseq=8

http://www.railpictures.net/viewphoto.php?id=88731&nseq=18

Larry

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Posted by dinwitty on Thursday, April 23, 2009 5:32 PM

 

I would have to think because of MUing, you have to know the "front" from the "rear" to understand direction when connecting up for MUing. Just like our DCC now, you could set up your engines in the wrong direction.
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Posted by dehusman on Thursday, April 23, 2009 5:09 PM

BRAKIE
So,some roads place a "F" on the front end of the "B" unit.

 

By Federal law ALL locomotives in the US have to have a F on the front end.

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Posted by BRAKIE on Thursday, April 23, 2009 3:33 PM

grizlump9

 while we are on the subject of "B" units, didn't some of the covered wagons have a hostler control station inside so they could be moved about independently?

grizlump

 

Some roads consider the end with the control stand as the front.

Of course railroaders had a hard time telling by looking.

So,some roads place a "F" on the front end of the "B" unit.

 

http://www.railpictures.net/viewphoto.php?id=178066&nseq=9

Larry

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Posted by dehusman on Thursday, April 23, 2009 2:40 PM

grizlump9
 while we are on the subject of "B" units, didn't some of the covered wagons have a hostler control station inside so they could be moved about independently?

Yes, they did.

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Posted by grizlump9 on Thursday, April 23, 2009 2:29 PM

 while we are on the subject of "B" units, didn't some of the covered wagons have a hostler control station inside so they could be moved about independently?

grizlump

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Posted by GRAMRR on Thursday, April 23, 2009 1:20 PM

I have plans to couple my A-B and A-A sets with a drawbar, thinking that they'll look better coupled closer together, and shouldn't give me any grief operationally.  What do ya think?

Chuck

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Posted by dehusman on Thursday, April 23, 2009 1:01 PM

GRAMRR

Reading TrainsBuddy's post regarding back-up light placement on "B" units made me think of another question that I just took for granted. Apparently "B" units have a front and back end.  Connected in an A-B configuration, are the engines oriented with both "front" ends facing in the same direction or are they connected "back to back?"  What was general practice?

Some people have mentioned FT's.  They are in some respects a special case, since they are asymetrical, theat is the distance from the truck center to the coupler is different on the front than on the back.  they came in semi-permanently coupled pairs (back to back) so they pretty much had  to always be joined the same way since it was physically impossible to connect them any other way.

Other F units were symeterical so there wasn't any difference which way they were pointed.  While engines were assigned and operated as sequential sets they probably  were always back to back since if they came from a set, they went back in the same set so there wasn't an opportunity to turn them.  Once railroads split the sets up and did not try to maintain sequential sets, then it was whatever way the engines were available.  Since it made no difference operationally, there is no incentive to try an turn them one way or another.  I know that with hooded B units, neither the MP or UP attempted to keep them pointed in any particular direction.

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Posted by DigitalGriffin on Thursday, April 23, 2009 12:38 PM

Texas Zepher
I am certain every possible combination existed; however, when the units were permanently coupled from the factory the general (default) configuration was  "back to back". 

That's interesting. 

I usually see them coupled in photos as front-back.  You can tell because the exhaust fans on the roof sit slightly stearnside of the engine.  The exhaust side would be the "rear"

I wonder if they got switched around a lot.  I've seen a lot of A-A units back to back.

Don - Specializing in layout DC->DCC conversions

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Posted by Don Z on Thursday, April 23, 2009 12:25 PM

MILW-RODR

Perhaps I should have mentioned this since your OP was about "B" units. If you are reffering to 2nd gen diesels, like GP40's for instance, yes they did have a front and back. Most RR considered the cab end, or short hood, to be the front, and even in cabless 'booster' locos this was still considered the front. Often times RR's would have the manufactorer (sticking with EMD here) actually move equipement around, such as moving the dynamic brakes to where the cab used to be. now them are kinda neat lookin. I will be going with newer engines as I'm partially making a fantasy RR, but I think I may turn my existing GP9 into a booster unit. I don't care if Milwaukee Road never did it, in my MILW world they did.

Perhaps you should have read the thread that the OP referred to in his opening line to understand that he is indeed talking about F7B units, not 2nd generation locomotives. Here is a link to the thread:

http://cs.trains.com/trccs/forums/t/152414.aspx

Don Z.

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Posted by BerkshireSteam on Thursday, April 23, 2009 12:11 PM

Perhaps I should have mentioned this since your OP was about "B" units. If you are reffering to 2nd gen diesels, like GP40's for instance, yes they did have a front and back. Most RR considered the cab end, or short hood, to be the front, and even in cabless 'booster' locos this was still considered the front. Often times RR's would have the manufactorer (sticking with EMD here) actually move equipement around, such as moving the dynamic brakes to where the cab used to be. now them are kinda neat lookin. I will be going with newer engines as I'm partially making a fantasy RR, but I think I may turn my existing GP9 into a booster unit. I don't care if Milwaukee Road never did it, in my MILW world they did.

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Posted by Texas Zepher on Thursday, April 23, 2009 12:08 PM

GRAMRR
My railroad will have a number of A-B sets and I really never considered that B-units had a "front" and "back."

To really see the "front and back" of a "B" unit look at the FT.  It was obvious which end of the "B" was the front.

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