First, the basics. Track power - remove or modify?
The Hartland 4-4-0 has nice driving wheel pickups, and one of the tender trucks also picks up power. I decided to use just the tender trucks and to isolate the loco wheels. That was pretty easy to do, by removing the screw in the middle of the wheel, levering the driving wheels off with a flat screwdriver, and pulling the brush and holder out of the chassis. Then put the wheels back carefully.
Other locos may need you to dismantle the engine and get at the motor in order to isolate the track pickups. Some LGB locos have plugs with wires on the ends of the pickups that you can pull off, after opening the bottom of the loco. Almost all of them are a little different in design.
I got out the components to photograph and labelled the pic.
I am using 2 switches - one for the main On-Off/Charge and the other for Track - Battery. They don’t need to have a center-off option, as turning the main switch to Off kills everything and lets you plug in the charger. Most conversions like this don’t need a track-battery switch so consider it an option if you have tender pickups.
The battery is a brick: 4x 18650 cells arranged in a rectangle (2x2.) I think it was sold for a robot floor cleaner. You can also get double size batteries, with twice the cells and twice the capacity, in either a brick or a flat pack.
A note on the Crest Revolution throttle I am using, which has a small add-on board with connector blocks, and a lot of wires, left over from the C-16 where it was used.
The little connector board provides power in from the battery and power out to the motor. The other connectors are for headlights, etc., which I didn’t use.
The wires that you see all curled together consist of
- Speaker connection wire black/white pair with big red plug on the end,)
- Binding switch (red push button, which you use to tell the board to go into bind mode and listen for a transmitter signal. When it finds one, it ‘binds’ itself and expects that transmitter to send it commands.Hidden under the board.)
- Chuff trigger wires.
The chuff trigger is not strictly necessary - these throttles will chuff quite realistically based on the speed you tell the loco to go. I like them so this loco is getting one.
I use a 5.5mmx2.1mm power plug and socket, as they are standard in the LED strip business and therefore available quite inexpensively. If you haven’t had much experience with Lithium batteries, then get a decent charger, like the Tenergy one:
If you have one of those, then there are some chargers that are much less expensive for backup; even has a red/green LED:
(Just make sure you get one with a US wall plug, and the type for your battery. 14.8VDC LI batteries charge at 16.6V.)
Then I turned to the tender and removed the trucks and the 4 screws from underneath. [Most tenders come apart that way - either screws underneath or hidden somewhere on top.] You may have to disconnect wires from the trucks if it has pickups - the HLW truck wires stayed underneath and came away with the truck, so it was easy. There may also be a wire to the rear lamp, or to the rear power sockets, so you will have to decide what you are going to do with them.
As a general comment, adding RC is just substituting power to the motor from the on-board throttle board, instead of collecting it from the track. The lights should continue to work as they did, unless you want to change them - swap the bulbs to LEDs (automatic directional operation,) or make them controllable by the throttle electronics.
This tender has room for everything and is a sealed box, which is good!
I also taped some styrofoam underneath to protect the steps, whcih protrude underneath. You can imagine that working on the tender floor is going to put strain on them unless they are protected.
and now we can start figuring out where everything is going to go.
Here I am juggling the components, to see whether to put the battery in the back and the speaker in the front, or what. The tape is useful for marking center-lines, etc. The final arrangement of pieces was/is much like you see here.