SRRL #10

Sandy River & Rangeley Lakes Railroad #10
2-4-2T Forney

​​LGB 27253
Features: battery power & R/C, lights, sound, smoke
​Status: fully operational
Brought to LHRR: January 2018

Sandy River & Rangeley Lakes Railroad, in Philips, Maine, is a 2-foot narrow-gauge railroad. There Forney is #4, but my LGB version is a decent model of it, in my opinion. I didn't make any paint or lettering changes to this locomotive. It was the first g-scale engine I owned, and so my changes have been purely internal. 

Disassembling an LGB Forney

While a difficult challenge at first, and tedious thereafter, taking apart an LGB Forney is not actually all that hard. I used diagrams from LGB to help me understand what is where when I first took my loco apart. They may help you too! But if you're still stuck, don't hesitate to reach out and ask me a question.

1. Removing Decorative Pieces

  • Remove the catwalks on either side of the boiler via the single screw that holds each one in place. 
  • Pull out the grab rails next. Start with their black supports and then carefully angle the gold railing out of the hole in the front of the cab.
  • Next, pull out the black tubing on the sides of the boiler. They don't have any screws.
  • The last thing to remove is the catwalk on the front of the loco. Pick up the front end by the smokebox so the pony truck hangs down freely. Grab the catwalk and slowly slide it forward. It'll come right off. This is necessary to get the smoke box off.

2. The Cab & Bunker

  • Remove the ash dump from the bottom of the cab. 
  • Then you can access the 6 screws to pull off the cab/bunker. Be careful!​ The cab is attached to the loco by the wiring for the lights. Once you get the boiler off, you'll be able to disconnect the wiring.
  • There are two smaller screws that are under the ash dump that hold the firebox in place. Remove these next. You'll be able to pull out the firebox a few inches. There are two screws holding the switch in place. Unscrew these and you can pull the firebox away and set it aside. 

3. Boiler & Smokebox

  • To remove the boiler and smokebox, you have to remove the screws on either side of the loco. There are two larger screws between the gold bands on the boiler and two smaller ones right behind the smokebox on the boiler. Be very careful with the smaller screws! Mine were stripped. 
  • The smokebox comes away first. It'll come forward, but there is a pin in the bottom of the piece. As when pulling off the catwalk, lift up the loco's front end, push down the pony truck slightly, and wiggle the smokebox out. It's easier than it sounds -- just watch what you're doing. 
  • NOTES: Let the smokebox hang to the side while you pull out the boiler. You'll be able to disconnect some of the wiring in a minute. The boiler is a slightly odd shape. The bottom is mostly empty space, except for about 1" in the front that holds the boiler in place. 
  • Pull the back of the boiler straight up so it's at an angle. Now you can pull it forward a few inches. 
  • To finish pulling these off we need to do some work with the circuit boards...

4. The Circuit Boards

  • Pull off the two 4-pin connectors on the bottom board. This will completely detach the switch from the firebox. Set it aside. The other is for the motor block and track pick-ups. 
  • There are also 4 single-pin connectors wedged between the others. Pull these all off. It will make getting to parts easier. However, some things are soldered to the board, so the only way to get them apart is to cut the wires. I did cut them because I'm changing the boards in my loco.
  • However, you can leave them and still get the loco apart -- it'll just be a bit trickier...
  • Next, carefully and evenly pull the top circuit board off the bottom one.
  • Now unscrew the three screws that hold the circuit boards in place. Once those are free, you should be able to pull away the smokebox, boiler, and cab (which should all be connected by some wires).

5. Weights & Motor Block

  • You don't need to remove the smaller rear weight to get to anything else, but the front (larger) weight needs to come out so that you can access the motor block. There are three screws that hold the weight in place. As you're pulling off the weight, be aware of the wires that run through it.
  • There are two screws with washers under the weight that hold the motor in place. You can see them in the left pic below, and they are removed in the right pic.

6. Inside the Block

There are only two reasons I can think of that one would need to access a motor block of any loco: to replace a part or to grease the gears. As you can see, mine are well greased (it's brand-new in these photos!), but I got into the block to figure out what pins are which on the 4-pin connector. As you can see from the photos, the two outer pins are for motor power and the two inner ones are for track power pick-up. 
To get inside...
  • Flip the loco over. There are 4 screws on the bottom of the motor block.
  • Removing the inner screws pulls off the bottom access panel (left picture).
  • Removing the outer screws will let you pull the motor block away from the chassis. Once you remove them, the only thing holding the motor block to the chassis is the side rods. I left those in place and was still able to access the motor as needed.​

7. Put it back together!

I was very careful to keep everything separate and labeled properly as I pulled my loco apart. There are many screws, and they all look so similar! I suggest you do the same with any loco you may pull apart. This will make replacing and reassembly much easier! 

Modifying #10

When I determined what I wanted to do to this locomotive, I came up with this list of features I wanted the engine to have:
  • Control via remote control with power from an on-board battery (rather than track power)
  • Adding sound
  • Keeping the lights (front and back only, I took out the cab light)
  • Keeping the smoke but making it optional
​

1. Preparation

This is my original wiring diagram I used to plan my engine. Below are some of the technical specs of the parts. This is actually how the engine turned out.
  • ​Smokestack - original to the engine
  • Headlamp - original to the engine (used a resistor in-line on positive side)
  • Speaker - 8 ohms
  • MyLocoSound sound card - 
  • RC Trains Deltang receiver circuit board (Rx65b)
  • Motor - original to the engine
  • Tail light - original to the engine, resistor wired in-line on positive side
  • SPST switch - controls smokestack, otherwise battery would drain. This allows the unit to be controlled independently of everything else, but it still relies on the main switch to be ON.
  • SPDT Switch - ON : CHARGE
    (Originally I wanted a switch that would give me options ON - OFF - CHARGE. But, since CHARGE is an open loop without the barrel jack plugged in, it is effectively an OFF option so long as the loco isn't plugged in.)
  • Charging socket -
  • Auto-reset fuse - used to protect components from issues, can be wired on either side of the battery in this configuration
  • Battery - 14.8v Li-Ion battery from Only Batteries

2. Getting Started

I want to keep the engine looking as real as possible when doing a project like this, so the goal is always to hide some of the new electrical components. Step one of actually working on the Forney was cutting, drilling, and reinforcing so I could put the charging port and main switch under the coal load at the back of the cab. 

The speaker for the sound card went into the steam dome. I drilled a couple of small holes on either side of the whistle so sound can get through better, and I built a shelf inside the dome for the speaker to sit on. This also acts as a baffle, forcing the sound up and out.

The switch for the smokestack was originally going to go in the sand dome, but I never got that worked out. Instead, I took advantage of a factory-made hole in the back of the engine. I had to make it a little bigger, but it works well. I filled excess holes and painted everything to match the cab. 

The sound card has an IR reciever on board the card and also a second one on a lead. I mounted this exterior one to the underside of the running boards. I often forget it's not a part of the original model. 

The two circuit boards are mounted in the same place the original was. I built a small styrene housing for the MyLocoSound card, and the Rx sits on top of that. The smokestack also has a board. This one sits on the bottom of the boiler weight. 
Something else that I did to this loco was replacing the factory-installed hook-and-loop couplers with Kadee knuckle couplers. I used item #790. It requires a bit of work, but it not only allows for more realistic-looking couplers, but also gives the loco a front coupler (which this Forney did not come with). 

3. Test Runs

4. Notes and Changes Made

This engine was started in early 2018 and completed the following year. Since then, I have learned a lot about almost every aspect of this work. In 2024, after my trains were packed away for a while, I took out the Forney and it wouldn't run. I was also reminded that I had some lighting issues. So I opened up the loco to find that my motor block pins had come apart. After further inspection, I also discovered a mistake I'd made originally. So work had to be redone. The moral: Work slowly, pay attention to details, and don't cut corners.

On a separate note, if I had to pick one thing I'd do differently, it'd be the power input. The battery is wonderful, but I wish I'd wired it so that track power is still an option with a switch that can be set to CHARGE - TRACK POWER - BATTERY POWER. Despite my best efforts, I don't think the smokestack will run off the battery. It just needs too much voltage.

Oh, I also wish I'd found a small enough connector to disassemble the wires that lead to the smoke box. Currently, none of that can actually be removed, which is annoying.

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