CR Specifics

The Plan

Taking Off the Shell

Kadee Coupler Upgrade

Flexicoil Bash

Battery Power




Speaker Placement


Control Panel


CR Specifics






390,000 pounds

Tractive Effort

83,000 pounds

Prime Mover

20 cylinders

Horse Power

3,600 hp

Fuel Tank

4,000 gallons


Conrail used Flexicoil trucks.  These trucks can be bashed off of USA Trains HT-C truck side frames that come with the SD40-2 loco.


The horn needs to be altered and moved to the side of the cab top (depending on road number).


Sinclair antenna and a cab signal box also need to be added.



The Plan

more info to come...



Taking Off the Shell

There are 6 screws on the underside of the shell to take off the long hood and 4 other screws to take off the nose section.


Underside of the frame.



Flexicoil Bash

Conrail used Flexicoil trucks on this loco.  These can be bashed from USA Trains HT-C trucks from their SD40-2 loco.  A great comparison photo can be viewed from the Conrail Cyclopedia website.  Please note that this photo compares the Flexicoil truck on the front of a loco, while the HT-C truck is a picture of the rear of the loco.  This makes the parts line up, but are actually wrong for prototyping.


Later Note:  These side frames a proving to be difficult to mount on the AC brick, so I may go back and alter the original AC side frames.

Take Apart Side Frames:

All parts of the side frames need to be taken off, including the spring loaded wheel mechanism as pictured here, as well as the brake cylinders on the other side, which can be easily popped off.

Remove Brake Cylinders:

Pictured here are the stock HT-C truck frames with the brake cylinders and wheel journals removed.

Basic Cuts:

The basic cuts include:  cutting out the parts above the frame which will be remolded, trimming the top of the frame to make the actual frame beam thinner above the three wheel journals, cutting the ends such that one end will clear the stair wells (this was originally the end by the fuel tank) and the other end is cut flat where another molded piece will be added.

Motor Tool Cuts:

I used a motor tool to change the shape of the frame beams on the two ends.

Added Parts:

I need to mold or easily create the parts I chopped off!


I'll get there eventually.



Battery Power

I choose to use Locolinc with battery power for motive control.  All locos will be equipped with a total of 18 volt 5 amp batteries.  In order to achieve this in most locos, including the SD45, I used three 6v 4.5AmpHr batteries in series.

Power Sonic 6v 4.5AmpHr batteries:

Three of these batteries are wired in series in most of my locos, providing a total of 18v @ 4.5AmpHr.

Fitting in the Batteries:

In order to fit the batteries, the steel square "U" shaped beam needs be trimmed down some, so that the batteries can rest on it and fit in under the roof.

Side view of Battery Placement:

I found this the best way to place the batteries, allowing for maximum space for the other components.

Weight Balance:

Since the speaker is now in the fuel tank and most of the batteries are applying their weight on the rear of the loco, I decided to retain one of the weights on the forward side of the loco.  The will keep the trucks pulling the same power and allows for more tractive effort.




Of course, batteries go dead.  So I added some MU plugs to all locos with the following four connections:  two battery (+/-) and two for speaker (+/-).  The loco has a main on-off-on switch to choose from its internal set of batteries or an external set of batteries, either coming for a battery car or another dummy loco.  The two speaker connections are a speaker output for when I have a dummy trailing loco with a speaker.  Its always nicer to hear the sound coming for both locos!

MU Rcepticle:

These four pole receptacles were actually creating by combining two 2 pole plugs.

MU Plug:

The plug was also created from two glued together.



Locolinc Control

Although I favor DCC in smaller scales, I went with battery power and wireless Locolinc receivers in G scale.  I can only imagine maintaining perfect powered track continuity and wiring outdoors is more trouble then its worth.  And not even having my own layout yet, allows me to run wherever I choose, including temporary track setups in the yard.

5 Amp Locolinc Receiver:

The SD45 is quite a power hog, although it is one of the more lower current rated locos out.  This unit requires the 5 amp Locolinc receiver that is capable of selecting power from the wheel pickups or batteries (which ever provides the greatest power), although I choose not to wire to rail pickup. 

Receiver Outputs:

This receiver also has 3 outputs that will be used to control the horn and bell on the Soundtraxx chip.  This requires a converter circuit of opto-osilators to be used for the function control, and the automatic engine rpm sounds.



Sound with SoundTraxx Sierra

I've been using the SoundTraxx Sierra system for all locos.  I feel this is the best bang for the buck.  It also has 2 additional lighting effect outputs that can be used and for most of these modern locos, ditch lights are a bonus!  The Sierra chip can be powered off its own 6 volt battery, but since I'm filling the loco up with batteries anyway, I decided to build a voltage regulating circuit off these batteries. 

SoundTraxx Sierra Chip:

Here's the chip.

Voltage Regulator and RC Interface:

Locolinc needs to control the Sierra chip by using some simple opto-osilator circuits for its remote and automatic engine rpm sounds.

The setup:

Shows the layout of the components.



Speaker Placement

Since I choose to use batteries that take up most of the room in the loco, including the location of where the original speaker is mounted, I needed to find another location.  Only place left, the fuel tank!  In my opinion, the fuel tank is the best location for several reason; 

1)  The speaker will face down and the sound will bounce back up off the track and road bed and although some of the sound is absorbed, the scattering sounds makes more for a realistic effect, rather then blasting straight up as in the original placement.  

2) The fuel tank can be fully sealed to create a great speaker cabinet that will greatly enhance the sound quality.  

3)  You can fit a larger speaker! 

Of course, their are some tricks to this install...

Speaker Selection:

I'm using larger speakers of size xxx by xxx with a magnet of xxx.

Fuel Tank Placement:

For better weight balance as previously discussed, the speaker needs to be placed in the rear of the tank to allow the weight to hang down in the front.

Fuel Tank Mods:

Underside of the frame.

Fuel Tank Mods:

Here comes the tricky stuff.  In order to get this bigger speaker to fit, a few things need to be cut out.  First is to cut the floor of the fuel tank of the shape of the speaker.  This is some think plastic and allows for more than 1/8th inch additional space.  This will later be covered with speaker grating for protection.

Speaker Placement:

The speaker will hang in the whole, so some supports will need to be made to get the speaker at the appropriate height.

Frame Mods:

Now that the speaker is sitting in its place, you can notice that the magnet is still a little too high to get the fuel tank on.  A circle the size of the magnet needs to be cut out of the frame.  Again, this thick plastic allows for more clearance and will be supported by the metal beam.

Seal the Enclosure:

I sealed all around the speaker inside and out with silicone and added on a speaker grate cut from a round 12 inch speaker grate.  Once the fuel tank is mounted to the frame, I then sealed around it and the opening cut for the magnet for an air tight enclosure.  



Custom Lighting

Since all the wiring was ripped out, I found it easiest to redo everything from scratch and use white LEDs.  I also added some other small circuits and switches for better lighting control.  

Head Lights:

The headlight has the option to be on bright at all times, or automatically for from dim to bright when the loco is in motion.  The rear head light has a similar set up where it can be on all the time, or off when the loco is stopped, and on when the loco is in motion

Marker Lights:

Marker lights are front on/off and rear on/off in red lights.

Night Lights:

This has a main on/off that includes the number board lights, walkway lights, porch lights, and custom built stair well and traction lights.

Custom Lighting:

Porch lights were cut into the shell in the front and back.  I also built a mold for stair well and traction lights.



Control Panel

Well, we need some controls here.

- Main on-off-on for battery selection of internal or external battery source.  

- Main on-off for sound.

- Two push buttons for sound programming and volume control.

- Three fuses:  main 5amp breaker, Sierra 0.5amp breaker, Lighting 0.5 amp breaker.

- on-off-on for head light: always on or auto dim/bright modes.

- on-off-on for rear head light: always on or auto on/off modes.

- on-off for ditch lights so that the lights can be off when the sound is on.

- on-off for front marker lights.

- on-off for rear marker lights.

- on-off for night lights.

The Control Panel:

Here's all the controls I'll think I'll ever need :)