Large Scale Central

A "B" unit with a NW2 or GP38?

Modeling Motive Power
#1

I recently acquired an Aristocraft powered “B” unit and I want to use it as a helper with my USAT GP38, NW2 and S4 when needed.

I would have preferred to get a USAT “B” but after performing a test where I placed the “B” a few feet behind the engines it kept pace pretty well.

It is not good for the gears if the lead engine was being pushed or continually dragging the “B” unit.

After testing each USAT engine with the Aristo “B” and looking at the lash up from all angles I’m not 100% sure of this arrangement. it does look a bit odd but why wouldn’t a cash strapped RR in real life use what ever they could to get the job done? We are talking freight trains here.

If I do keep it I will have to try and lower it a bit. I don’t know why Aristo engines seem to sit so high?

#2

You will find a prototype for nearly anything and “B” Units with switchers were more common than you think. “B” Units had a full set of controls like a “A” unit and in San Bernardino the ATSF would sometimes use a “B” for yard switching. It just comes down to whats on hand and how bad it needs to get done.

#3

Bob,

ATSF was only one railroad that ordered “B” F units with hostler controls, most others didn’t. After the first run from EMD, ATSF quickly realized that hostler controls were not that useful for operations. Ironically, ATSF was also one of the few railroads that ordered “A” & “B” units as separate units (ie, both units connected with couplers, not drawbars). The picture you posted above would be an example of hostler operations, or movement of light engines without railcars attached.

As a sidenote, one of the reasons “B” units fell out of favor with the railroads was because they didn’t have operating controls. As the 1st generation, lead to the 2nd generation of EMD products the railroads decided that it was more efficient to simply order more “A” units (units with cabs). History always seems to repeat itself, because many of the leased units (older SD40-2’s) now are considered “non-occupied” or “B” units with a cab. Depending on the leasing company the cab can be completely stripped, or only a toilet, or radio removed to make it non-occupied.

#4

Hi Todd,
I don’t have any problem running Aristos and USA engines together. Once you have a load, the faster but less-powerful Aristo B unit will give its all and then the slower more powerful GP will take the remaining load. Electronically the current should fflow where it’s needed and strain on the gearing will be no different than hauling a significant load.

The Later Aristo and current Polks FAs are much much lower riding. Do a quick google search to find out what folks are doing to lower these engines…it’s well worth the effort.

I’m currently finishing a USAT f3 B-unit to run between a set of lowered FA-1s. They ride at about the same height. The b unit contains a high capacity battery with RC board and ultra-low resistance 31mm ball bearing wheels from LGB.

I’ve also run the b unit between GPs too. Although nw-2s were often set up for MU, I don’t believe there were many ALCo s-4s that had Mu.

#5

Well that is good to know that I can run the Aristo and USAT together. It is also good to know that there is a prototype example.

With just a quick look underneath I think I can separate the body from the floor and maybe trim down the screw mounting posts inside by a quarter inch and then put the floor back on. Could it be that easy? I doubt it. LOL

Thanks for the info guys.

#6

I’ve done that on my two older engines with relatively good results. The benefit to that is mechanical simplicity. You won’t have to adjust the bolster heights or the couplers (since its a B unit). Be aware that the car floor ends will have to be modified to accommodate the circuitry.

On my other Aristo Fs, and subsequent engines I may buy, I prefer to cut out the bolsters from the car floor and re mount them higher up on the frame. The benefit to doing this is that the fuel tank and steps will all be at the correct heights too.

#7

CP and CN “B” units had hostler controls in a lot of them. If you are using a Crest Revolution throttle in each unit, they can be programmed to run with any other unit, no mater what gearing each unit has…of course saying that, some would suggest that I’m trying to push radio control, battery operation…

Fred Mills.

#8

A note on running locos together… if they are reasonably close, the load of the train will equalize the speed between them… the “faster” one will take more of the load and naturally slow down a bit.

Greg

#9

My thought is to drop the body down onto the frame by 1/4 inch if there is room to do it.

I have an aristo railbus and that suffers from the same problem of riding too high on the trucks. It looks very spindly if you know what I mean.

With that one dropping the body or recessing the motor block and front truck was going to be too much work and I didn’t want to butcher the railbus so instead I fashioned side pieces that makes it look like the frame is dropped lower and tighter to the powered truck.

Thanks for the second on running the USAT and Aristo together Greg. I have run my USAT diesels together before and my bachmann geared steamers but a diesel and a steamer together now that might cause a problem due to the steamers running much slower.

Part of my train fun on my layout is to have a diesel train running and a geared loco as well. I use a TE to power everything at once and it is fun to avoid running a faster train into the back of the slower. I do this by timing their speeds and sending one into a passing siding or holding up the quicker in a block then sending it along to chase the slower again.

#10

A prototype note on using an Aristo B unit with an NW2 or GP38.

The Aristo B unit is an Alco FA B unit. When first delivered, Alco FAs would not MU with EMD locos.

Of course in later years many were upgraded to MU with EMD and other loco manufacturers. And since your GP38 is a later model loco when compared to when the NW2 and Alco FA first came out you can say your B unit was upgraded to MU with your EMD NW2 and GP38 locos.

I’m not 100% sure, but I would assume an Alco FA B unit could MU with an Alco S4. So that combo likely works OK prototypically.

#11

Todd,

Check out George Shreyer’s tips page to lower you loco.

http://www.girr.org/girr/tips/tips2/fa_tips.html