Large Scale Central

Bachmann 2-8-0 CONNIE + RCS + MyLocosound

I have recently updated the RCS installation in the Bachmann Spectrum 2-8-0 Connie. This particular loco still has the original axle gear which will eventually be replaced with the new Bachmann axle/gear assembly as soon as one becomes available. GETTING STARTED The Bachmann 2-8-0’s have a few problems as they come. The tender trucks have side frames that are held to the tender bolster by self tapping screws that are too short. These screws need to be replaced by longer screws or the bolster will eventually break off. Start by removing the simulated side frame spring moulding by simply pulling straight out. Then unscrew the self tapper and replace by a longer screw about 10 mm long.

WORKING ON THE MOTOR & GEARBOX. We recommend you make sure the screws securing the motor to the gearbox and the gearbox screws themselves are tight. Our sample, and many others have had them loose. If you are sure the screws are tight you can skip the next step. First lay the loco on its left side and carefully remove the very small shouldered screw that holds the Johnson bar rod to the valve gear. Store it carefully as it is not replaceable. Now support loco upside down in packaging material and remove the 4 small screws that hold the ashpan cover on. Again, store them carefully. Lift off ashpan cover and remove the four big screws that hold the chassis to the superstructure. Remove the long screw under cylinder saddle at the front and the superstructure will separate from the chassis. Be careful that the piping is not bent as you proceed. Remove the four screws that hold the gearbox plate on and set the parts aside. The two pictures below show what to check for in the gearbox. Remove and clean each screw. Apply Loctite® to each thread before replacing them. You can also use a clear nail polish varnish.

Replace the gearbox and make sure the four screws that hold the bottom gearbox plate on are tight. Do not overtighten screws when replacing them. MOTOR SUPPRESSION Bachmann have mounted a small PCB that contains a suppression circuit on the end of the motor. The PCB has quite high value capacitors that will cause the RCS ESC to overheat. We recommend that you remove this PCB. There is no need to add any suppression to the motor. 2.4 Ghz R/C is impervious to RFI.

Now feed the supplied Red/Black Tender-Loco harness wires with the larger hooked socket into the rear of the loco, down behind the firebox pcb, above the weight and out through the hole the motor fits in. Then solder them to the original 2 pin plug. Cover joins with heatshrink tubing to prevent accidental shorts. REASSEMBLING THE LOCO PARTS. To enable easier refitting of the boiler use a countersinking tool to chamfer the edges of the four firebox mounting holes in the metal casting. This can be seen where the tops of the holes are shiny.

Be very careful reassembling the loco to make sure the motor wires are tucked up into the boiler and the sanding line pipes on the boiler fit in the correct spaces on the chassis. Replace the body to chassis mounting screws. 4 x Firebox & 1 cylinder saddle. Replace the shouldered Johnson bar screw. This can be really tricky to do so take great care not to lose the screw.

FIREBOX MOD & LOCO TO TENDER CABLES. Before replacing the firebox tray remove the little plug (CON 7) on the firebox PCB that comes from the loco track pick ups. This isolates the loco from the track. The supplied 2 way Red/Black harness is either knotted to stop it being pulled through accidentally, or a cable tie used. Also knot the 2 x way and 4 x way Bachmann cable and locate in the slots provided. Now replace the firebox cover and the loco wiring is complete.

INSTALLING BATTERIES. I still like to use 2 x 7.2 twin stick Sub “C” NiCad cell battery packs. These are fitted with Tamiya plugs. Even though the Bachmann 2-8-0 tender shell is shallower than the 4-6-0 these packs will fit laying down underneath the top of the render and still leave enough for the 3“ Phoenix speaker. We secured them with strips of double sided tape and silicone adhesive. You could use 2 x “AA” 7.2 volt packs made up in twin stick shape are an alternate choice as they will fit along the tender shell sides. Bear in mind current over ½ amp will shorten battery life.

CONTROLS OUTSIDE OF THE TENDER SHELL. The RCS BIK-CONNIE switch and programming pushbutton were installed in the top of the shell with access through the water tank hatch. The charge jack assembly was mounted on the rear of the tender with access for the plug through the ladder.

LAYOUT OF R/C COMPONENTS AND SOUND. A regular Phoenix 3“ speaker was mounted in the provided place. If you need a more powerful speaker you will have to remove the mounting plastic and replace with a suitable oval speaker. The RCS and MyLocosound components were attached to the tender floor with silicone adhesive. The RCS # PRO-3 also powers the loco lights / smoke and MyLocosound via the screw terminals marked + & -.on the decoder part. These are fused 1 amp outputs. The 2.4GHz R/C receiver plugs in upside down on the decoder part. It is most important that the pins are lined up correctly. The small two wire socket with Blue and Yellow wires near the speaker is for the rear light.

I have the above article available as a pdf instruction manual http://rcs-rc.com/PDF/Acessories/Installation-kits/BIK-CONNIE.pdf The CONNIE can be wired up a number of different ways, depending on the complexity you wish use. These instructions show the alternatives available. PARTS USED. 1 x # PRO-3v3 ESC (With SPEKTRUM DSM2 RX). 1 x # BIK-CONNIE installation kit. 2 x 7.2 volt 2500 mah SubC NiCd packs in series for 14.4 volts. 1 x # Y-CABLE to put battery packs in series.

Thanks Tony. Very timely information for me as I am about to rip into my Connie for a conversion. I’ll be setting it up for trail car, but lots of your tips still apply.

Hi Jon.

If you are not having any special wiring changes you can simply connect the trail car output to the track pick points in the tender. Don’t forget to remove the track pick ups in the tender and the CON7 plug in the fire box. Then the loco will behave as if it were running on track power.

Thanks Tony. Nothing special other than including a Track Power / Battery Power DPDT switch in it somewhere if it isn’t too complicated. Seems like that might require one more pair between tender and loco. I might just forget that and do as you suggest - or use two switches. Gotta think about that.

I will be extending the chuff trigger to the trail car and putting a speaker in the tender too. Lots of interconnections. I may try and do it with 5 wires between the trail and tender.

I also thank you for this timely article. My Connie is on the ready track to go to the shops for a complete overhaul. Your tips are very helpful.

Hi Jon.
Yes, if you want track power or battery power the easiest way would be to remove the CON7 plug from the firebox pcb and extend the track power into the tender via a suitable two way connector. Then remove the tender track pick ups from the terminals on the tender floor and combine them with the two new wires coming from the loco pick ups. Mount a DPDT switch in the tender. One side of the switch would be connected to the track power and the other side would connect via two wires to the ESC in the trail car. The middle two terminals of the DPDT switch would then go to what were the original tender pick up connections on the tender floor.
The loco would then run on regular DC track power OR battery power without any other wiring changes.
Yes you can extend the chuff wires into a sound system mounted in the trail car. I would use the chuff timer two way connection the other way around so they could not be mis plugged. Or use a four way connector between the tender and the trail car. If the speaker will be in the tender you will need a six wire hook up.

Great idea Tony. Thanks. My standard for sound is a 3 conductor plug. I planned on supporting series / parallel speaker wiring, but on my 1:20 stuff I rarely double head, so it’s not needed. I want to experiment using the speaker common line as a return for the chuff trigger. If it works I could get sound and chuff in the 3 wire cable.