I’m just guessing that though a “B” unit looks pretty much the same on both ends to most folks, it ain’t so with railroaders - real or modellers. In order to thwart the persnickety, how do I indentify which end of an EMD F3B was forward? For those who may ask, I’ve got an SP A/B pair (Athearn Genesis). Thanks!
John
This is probably only a detail that matters on drawbar connected units. Coupler connected units I am sure would get turned at some point.
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Were SP units drawbar connected to the A units?
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-Kevin
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If there is no hostler controls and no gear shift with 5 forward speeds and 1 reverse, why would it ever matter?
For a B-unit in service with other diesels, it doesn’t matter which end is forward. However, I believe that B-units had a control stand that could be used by a hostler, for moving the unit on its own - not sure if there was such a control at both ends, though, or just one.
Let’s hope that someone with more knowledge of the prototypes can clarify that.
Wayne
The front of a B-unit is the end with the little teeny F painted on the side.
For example, my Athearn BN 725, an F7B, has such a little F. It is on the end where they don’t normally put the steam generator.
And, for those of us using DCC, it is important in such things as consisting.
I had a quick look at the pictures of Athearn’s SP F’s. MY, there are a lot of them. I didn’t look at all of them (hey, it’s not MY problem), but I did see that an early F7B didn’t have an F, while a Bloody Nose F7B did.
Ed
When EMD drawbar connected FT’s, they were “back to back”.
I think every EMD builders photo or multi unit drawing I have ever seen shows them back to back, even three unit lashups, lowest number A unit back to back with the B unit.
But even in the early days when loco sets generally stayed together, they would get switched around during servicing, etc.
I think the one case were you might have seen an effort to keep them back to back would be passenger units. This would keep the boilers together in pairs. The one exceptionto that might be the ATSF. Most of their passenger F units did not have boilers in the A units, can’t remember off hand how they were typically arranged.
Sheldon
Sometimes the railroad would decide to make the “F” at the other end. I wonder what would have them make this change, though?
See the note at the lower center for this PRR E-7B:
PRR_paint_A_edited-1 by Edmund, on Flickr
The wiring of the MU plug would have to be modified so that the locomotive would move in the same direction as the reverser handle indicated.
Regards, Ed
Ah, me. Once again, unexpected complexities.
[*-)]
John
Look at the roof. The steam boiler exhaust is to the rear. The front has a blank plate instead since this is where the cab is on an A unit.
Bingo! Thanks a lot!
John