M&K Junction Railroad

M&K Junction Railroad
Another train of eastbound coal crosses the Cheat River

Monday, March 28, 2011

New Life for an Oldie

The All-Nation B&O B18 Ten Wheeler that you can see on other posts on this site is an 'old school' O Scale loco that I bought in the '90s and the loco was probably 40 years old at that time. This specimen of the B18 has a sand-cast bronze boiler that dates it to no newer than the late 40's or early 50's.

Since these were produced as kits and assembled by individual modelers, the running characteristics of each example can vary greatly. This one had sub par running performance. Since this one of the few models of B&O steamers made, I wanted to salvage this one for use on my layout.

I decided to go all out and see how well this loco could be made to run and I invested more money into upgrading this steamer than it is worth.

For starters I obtained a Faulhaber coreless motor from Micro Loco Motion (www.micro-loco-motion.com). The ball-bearing Faulhaber 2342 12CR motor will deliver 17 watts of power with a recommended torque of 16 mNm. The motor is 23 mm in diameter and 42 mm long with a 3 mm shaft 10 mm long. The motor had one quirk, the mounting holes are on the opposite side of the motor from the shaft.

I sought out Joe Foehrkolb of Baldwin Forge & Machine (home.comcast.net/~omodeller/) known for his 2 rail to 3 rail conversions and upgrades to 'classic' O Scale. Joe had reservations about the coreless motor, especially with it's non-standard mounting; but he decided to take the job anyway. I provided a backup motor to Joe should he not be able to make the coreless work.

Joe solved the problem of mounting the coreless motor by fabricating a brass sleeve into which the motor fits and is held in place with a cap set screw. See the pictures below:

The gearbox on the center driver is a new Northwest Short Line Mod 0.6 ball bearing gearbox. Joe also fabricated a coupling utilizing rubber tube and two sleeves bored to fit the two very different diameter shafts.

The loco worked well after remotoring, but I thought that it could be more. The next step was to add a BEMF DCC decoder; but not any DCC decoder would do. The decoder had to be compatible with coreless motors and that meant high-frequency drive. Lenz, ESU and Zimo fit the bill as explicitly stating that they are fine for coreless motors. I generally use Lenz, but for this installation I choose an ESU unit. The Faulhaber motor draws less current than many HO locos, so an HO decoder was all that was needed.

I also installed an NMRA 8-pin wiring harness so that I could swap out any other 8-pin decoder in future. While I was at it I installed a warm-white surface mount LED into the heretofore unlit headlight.

After tinkering with CVs the loco ran better, but still had a tendency to hesitate. I figured that it was bad contact and resolved to fix the problem by replacing the tender, which I was going to do anyway, and use tender-mounted pickups for both rails. Recently I have discovered that it was simply the old, oxidized drivers that was the source of the problem and cleaning them up with a sanding sponge has just about eliminated the stalling. The loco will still get a new tender as the original tender has no rivet detail!

I find it ironic that this loco now has a motor, DCC decoder, and an LED headlight (surface mount no less) that were not even conceived of when this model was manufactured. Was it worth it? Economically, no; I could have had one of any number of modern die-cast steamers for the money that I spent on the original locomotive and the upgrades. However, I now have a model of a B&O locomotive that can join my fleet of DCC-equipped motive power and have another decade or two of use on my model railroad.

1 comment:

  1. I too remodeled an old All Nation B&O Ten Wheeler, but I chose to leave the original open-frame motor BECAUSE of it's running qualities...to start, one has to open the throttle wider than a slow run voltage, to get the motor to 'break loose'. Once turning, the throttle has to be backed off to avoid either a jackrabbit start, or spinning the drivers if hauling a heavy train.

    Why did I leave it like that? Simple...THAT'S the way real steam locos are...you have to goose 'em to start 'em, then back off to run 'em.

    How do I know? I own a 1/8 scale live steam Mogul (7.5" gauge) and it, and every other live steamer I've ever operated, runs exactly like that.

    From the other end of the stick, I am...

    Mark in Modesto