Hello! I'm super confused on how to convert a 2 rail model, of any make really, such as a split frame chassis or a modern Electric (DC) model to use the 3rd Rail, I have tried this conversion using a Marklin pickup but it didn't end up working at all, that is where my problem starts, I would... really, really, really appriciate some assistance in this field of "expertise" there is something I'm really hoping to pull off, I've been trying to model it for the Past 2 or 3 years rather unsuccesfully and its another Thomas Parody/Comedy that is a British one and Not American, although I'm super excited to share it with you guys and gals eventually ..
Hmm, I think it would be far asier to go from a 2 rail loco to 3 rail - all you really need to do is add the 3rd rail 'skis' to the underframe of the loco. You could just connect both existing pickups together, that way if a section of one outside rail is isolated to make a detection section, the converted loco will be able to trip it. In fact, I think ESU sells the pickup 'skis'.
Far more difficult to go the other way since the wheels and axles aren't usually insulated and that has to be resolved before the loco can even sit on 2 rail track.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
American DC won't work on Marklin HO 3-rail without some additional steps. Marklin 3-rail analog is AC voltage (think Lionel) vs the DC engine you are trying to use. Marklin's digital system is it's own protocol(s) (MM, MFX, etc.). Marklin's newer decoders support DCC. Marklin's Central Staion 2,3 and Mobile Station 2,3 offer DCC compatibility, too. If you have one of these Marklin controllers, then you can put a DCC decoder in the DC engine and with the added center prickup, you should be able to run it. This is essentially what Trix is in the Marklin line.
In converting, you have to watch for isolation/shorting issues. A split frame loco needs the motor completely isolated as both sides will become the same polarity - you don't want the shoe pickup to feed power back to the frame.
If you are running analog (AC) Marklin, then the only way I can think of making it work would be to repower the DC engine with an AC motor and reversing unit from a Marklin analog engine. I think it would be a huge job to do that and most likely not worth it. Marklin's stuff takes up a lot of room.
Going from Marklin to American DC/DCC is difficult, too. Marklin doesn't electrically separate the two outside rails like DC/DCC does. Some manufacturers do offer stuff that can be switched back and forth - ESU does and I think Roco might.
I run DCC, but I have a little Marklin from a kid. When deciding to get back into the hobby, I bought a little Marklin digital starter set to see if I liked it. I even successfully converted one of my engines from the 80's to digital. Today, if I was going to try to make something interoperable, I would seriously be looking at DeadRail/Battery operated. Kadee makes knucle couplers that fit european (NEM) coupler pockets and wheel sizes and flanges on modern stuff and modern Marklin track don't seem to be a problem anymore.
There are electronic reversing circuits which are small, with a relay and a bridge rectifier there'd be no need to swap out the DC motor to conver to running on Marklin 3 rail.
DCC would make it easy as well - if you are using a Marklin Digital system then you just need a decoder that 'speaks' marklin protocol - which a great many do (like ESU's). Drive to the motor is PWM DC so again the motor is OK.
Motors need to be isolated for 'regular' DCC as well - very few locos made these days have the motor grounded to the frame, at least not US ones. Even the lower end Athearn RTR series have done away with having the motor directly contact the frame.
I would really, really love to go DCC, and I will consider it, yes I have had German Marklin Locomotives before in the past albiet I never previously had a great selection of track to operate them on neather a controller at that point of time and still don't, but that has changed... well in terms of track, but I will have to get new one's Digitizing them seems really tempting! Also yes it is possible to convert Pre-war or Postwar Marklin Tin Track to Digital I've done a bit of reaserch on the matter and it is really amazing, I will certainly take all messages into consideration... Also the Hornby Dublo brand does match up with the German system well, I will have to use some new rail jointers, if I want to eventually use a few level crossings