Locomotive Roster: Arnold 2471; SNCF BB 25201

Last Christmas I was happy to receive this dashing looking locomotive from the SNCF; an Arnold 2471  class BB 25200 number 25201.   I had spotted one of these a while back and there were three things that I really liked about it:

• Despite the fact that its an older production model, details and graphics are very nice
• I liked the white/orange/black paint scheme
• I love the curved cab window styling on these French electrics!

The Arnold Model:

The Arnold model I have (#2471) was cataloged sometime between 1989 and 1994 and according to the database at Spurweite-N.  Given the time frame, this is obviously an analog model and will require conversion to operate on a DCC layout like mine!  Spurweite-N also lists a another version of this model (#82471) that allegedly was sold with a digital decoder installed. I find this fairly surprising (the available data for this supposedly digital version are the sames as my analog version.  While I don't dispute there was something like DCC around during the early 1990's I am a bit skeptical that Arnold would have sold an already digitized version.  It might be that the catalog dates for the digital version are incorrect and they reflect the early 2000's and not the '90's, which would be more believable).

The below photo shows the fairly impressive detail (in my opinion) for a model produced in the early '90's!

Don't confuse Arnold's model of the BB 25200 with their much earlier model of another and slightly similar BB 9200, which comes from the 1970's era and represents what I think would be considered rather crude detail, low quality graphics, and rudimentary mechanisms.  I'm basing this off of photographic comparisons which make the visual comparison fairly obvious, and I would expect the mechanical mechanisms to be fairly crude and representative of the first generation of N Scale models.

The Prototype:
The BB 25200 class was, and is, a bi-current locomotive able to operate on France's two main standards for electrical locomotives (1.5kv DC and 24kv AC - which is a legacy of France's pre-nationlization private railway standards before 1938).

These locomotives were produced for the SNCF between 1965 and 1975 and, from what I can tell, would pull both passenger and freight trains as necessary.

This electric locomotive, which I tend to think of as a 'box cab' given my American orientation, has some of the distinctive styling that I love about the SNCF - mainly those super-cool, styling curved window elements.  It reminds me of the sort of decorative flourishes' that were applied to cars, buildings, and all sorts of other engineered elements back in the 'old days'.

I'm also intrigued by the livery (another reason I enjoy the SNCF so much....despite being a state-run railway, the diversity of different liveries is pretty amazing, and most of them are pretty amazing and attractive!) which is described as the "Le Mans" livery.  I can't tell if Arnold did a good job or replicating this livery, the few photos I've found of prototypes in this scheme seem close, but something is not quite right.  I'm not too crazy about the precise shade, and being somewhat ignorant of the prototype helps to appreciate the model for what it is.  It is interesting, I can't tell if the base color is white, or more of a light grey? If it's light grey, then its very reminiscent of the current 'concrete' scheme that is frequently seen (grey with organge stripes).  So perhaps this livery was something of a predeccesor?

According to Wikipedia, many of these locomotives operated (and still do?) in the Rhone-Alpes region of France, which borders Switzerland and Italy, where the largest city is Lyon.

Perhaps not surprisingly, these locomotives have put in their time and many of them are being replaced by newer EMU's, Prima's and so forth.  Amazingly to me is that the last production of these was in 1975 and here, 35 years later, even a few are still in operation!


Converting to DCC:
As I mentioned above, despite the good quality of the casting and printing, this locomotive was produced before the idea of digital really took hold, so converting to DCC is somthing you'll have to do yourself (or pay someone, or find a friend!).

I was able to accomplish this using a tutorial on the French N Scale Forum, but as the original instructions are in French, I decide I would pass on the good knowledge I learned from this site and member "Oliv CTR" (Merci!) and contribute my own photos of the process.

One of the first things I learned from the French forum, is that there is not a lot of room for the decoder, so the thinnest decoder you can find is advised.  I used an Ulenbrock 73400 which is only 2.4mm thick and will fit nicely within the enclosure.

Removing the body is a little unusual, as you have to remove a screw from the bottom of the chassis, which releases the two plastic tank sections which then allow you to remove the shell.  Trying the remove the shell without remove the screw will probably wreck your locomotive.

Once the shell is off, you will see the PCB board, which is where most of soldering and digitizing operation will take place.  Remove the two screws which hold the PCB board to the chassis to work on the decoder install.  Once those two screws are removed, you can slide the PCB board off the motor contacts and metal base.

 Again, space is tight, so in order to add the decoder, something must be removed.  Following the instructions from "Oliv CTR" on the N Forum, I chose the same relatively 'blank' area as he did.  I don't really know if there are other options, but this location works well.  In the below photo, you can see some pencil lines where I planned my cuts.

A razor saw is a really nice tool for making sharp cuts in the PCB board.  I scored the bottom area of the cut-out area with a knife and was able to snap away the unneeded section of PCB.

One thing I've never done before (at least in the very few DCC conversions I've done myself) is to shorten up the wires prior to install.  My typical inclination is to assume that there will be enough room to hide excess wires away after everything is installed, plus I want the safety margin of extra wire...just in case!   Well with this loco there is no extra space, so I decided to shorten my wires before installation to get as little slack in the final install as possible!

The below photo shows the PCB board with the cut-out section for the decoder, as well as the PCB copper strip connection you will need to severe to the light and the diodes and capacitors that need to be removed.

With everything  but the white wire soldered, below is where the various wires get soldered.  While it may seem somewhat complex, being able to do all your wiring right on the PCB itself make this a fairly easy decoder install.

I chose not to replace the old-fashioned incandescent bulbs with LED's.  If you wanted to do that you would also need to find space for the resistors as well.

Putting the loco on the track, I'm always a little relieved that anything works that I have put a soldering iron to!  She runs nicely, if a bit noisely, which I attribute to a 20+ year old mechanism!

On the down side, the bulbs are extremely dim and the connections could probably use some cleaning as the light doesn't stay on consistently when in DCC mode.  The lights only work in one direction as well...hmmm....something to consider.