Kit: MX645R; IceCube28X18X09-2W; SuperCap17000uF; Seuthe#22; Firebox SMD LED
This is one of Hornby's classics - Battle of Britain, unrebuilt. Great model, and plenty of scope for enhancements. This one
is a relatively modern one, with the little Hornby 4pin connector between loco and tender, with DCC 8pin provision in the
tender, and space for a 28mm round speaker in there too.
We're not going to do it like that though, but we will reuse the connector - 2 of the wires will remain as pickups, but the
other 2 (currently for motor) will be retasked as speaker wires. We'll put most of the kit in the loco, and place a really
decent speaker in the tender.
Disconnect the loco from tender so we can work on it.
Opening the loco, we discover a good depth available under the chimney for a Seuthe #22 smoke generator. Not totally convinced
that the unit could be mounted exactly vertical, we mill just a tiny slither off the front of the block to be sure it will fit
We hard-wire the MX645, which sits on top of the chassis, mid-way along. The pickup wires are spliced into the existing wires
which join the loco's pickups and the 4pin connector. Motor wires (orange and grey) are soldered directly to the motor
terminals, leaving 2 of the 4pin's wires free for us to use for the speaker later.
A 17000uF SuperCap is connected up to the decoder for stay-alive, protected in Kapton tape.
Next job is to fit the firebox glow LED, which is an SMD component. We drill a 2mm hole for the light to shine through the
firebox door, and thin out the plastic from behind so that the LED can sit closer to the aperture - this will help the light to
shine through more effectively.
The Seuthe #22 unit is positioned into the chimney - with some additional heat shrink to enlarge the size, since the chimney
opening is wider than the Seuthe. Two rings of heat shrink is enough to fill it up about right, then we fix it in place with
some DevCon 5-Minute epoxy, ensuring that the Seuthe is correctly vertical, and the top is flush with the top of the chimney as
it sets. Patience required!
Fix the SuperCap right at the front with some Black Tack, and neaten the wires so they don't catch as the body goes back on.
With the loco part done, we move to the tender. The 8pin DCC socket is removed, and the pickup wires insulated as they are. The
other 2 wires from the socket were for the motor, but are now attached via the 4pin plug to the decoder's speaker wires. We can
therefore simply attach these to the IceCube28X18X09-2W and fix this onto the metal weight - fits in comfortably with no
modification to the metal or the plastic.
The finished model, complete with sound, firebox glow and smoke!