A few years ago I bought a pair of Athearn RDC units at a train show. The baggage/express unit was powered and the coach was dummy. A few months ago I opened up the powered unit to see what it would take to convert them to DCC and discovered it has a rubber band drive. I tried running it in DC mode and it had a herky-jerky movement to it. I’m thinking the best option would be to replace the motor and trucks but I’ve never done such a conversion and I’m wondering what might be a good replacement for what is in the powered unit.
I clicked on the Bowser ad at the top of this page because it showed such a motor and trucks but all it did was take me to their home page and I can’t find the item that was in the ad.
Remove the guts, turn them into dummies, and couple them to a Proto 1000 powered unit?
Don’t know about Bowser. Probably easier to call them and ask tomorrow.
However, there was an outfit called Ernst that made a re-gear set specifically for the Athearn RDC. Look in the Walthers on-line catalog for item 259-3. Out of stock but you’ll probably find one if you search.
Tried one of them once and didn’t have much luck. Probably not patient enough.
North West Short Line offers a number of power drive-units in their catalogue, including ones for re-powering a variety of manufacturers’ locos. My catalogue is an older one, but it shows at least one power truck made specifically for an Athearn RDC.
Please don’t take this negatively but…for the amount of money that you may wind up spending to remotor this unit; you’re likely better off purchasing an LL Proto 1000 RDC on the secondary market. Quite a number of them pop up on ebay for resonable prices in the $40 to $70 range (inspite of the current economy).
They’re VERY easy to paint strip and customize. Plus they’re heavy and generally run smoothly. I currently have two.
I did six of them with the ERNST drive, wheels from NWSL and new can motors, they run pretty well.
But it was a lot of money and work, and they required a lot of weight to help them run smoothly becuase the low gearing gives them realistic speed but lots of torque…
I don’t think ERNST makes any of that stuff any more?
NWSL also sold some power trucks, not sure what they are selling now, that could be used for this sort of thing.
NWSL’s power truck was called the SPUD - Self Propelled Underfloor Drive. They’re out of production now, but my local hobby shop, Train Shack in Burbank, had one in the used cabinet a couple of weeks ago – Google and call them (feel free to tell 'em Aaron sent you). That said, I don’t know if that’s the right SPUD for an Athearn RDC, or how/if you can convert them to DCC, or if one SPUD can pull two RDCs, or anything like that. But it’s a lead!
All of that said, I agree that the Athearn RDC, cool as they may be, are a lot of work for a not-so-great model. I think trying to find a Proto 1000 RDC is a better idea in terms of money and time. They are prototypical length and are overall nicer models than the old Athearns, which I think date back to when the real RDCs were new! And if money is no object, the Rapido RDCs are gorgeous! I can’t afford one but I’ve played with someone else’s, and… wow, wow, wow.
I had three of the Proto 1000 RDCs and while they do run very smoothly they are notoriously s-l-o-w. Top speed is about 40-45 SMPH.
NWSL does offer a speed-up gear set if you decide to go the Proto route and are annoyed by the non-passenger speed. If I recall the Budd RDC could attain 85 MPH.
I can afford a new one too but for the limited amount of use it will have in my operating scheme, I can’t justify the cost. Lots of used offerings on ebay to choose from at a fraction of the cost of new.
Hi there. How about taking the mechanism from a Bachmann doodlebug? It appears to be the appropriate size. With patience, you can find one used that won’t break your budget. The Athearn looks nice at shorter length on right curves… You could connect other dummies to it and make a nice set.
I think the rubber band drive were just the earliest ones from when they started offering them around 1960? I think the RDC I bought in the 1990s had more normal ‘blue box’ gearing, though it’s been in storage a long time (since the Proto RDC came out soon after I bought it, and I bought a couple of them).
I have thought of that since I have a couple those already that are not in use including an undecorated one that’s ONB. If I remember right I bought them from Trainworld at a close out price. I tried converting one to DCC and it didn’t go well. I can’t remember the issues but the guts are now in the box along with the shell and the bottom. I don’t think the powered truck would be right for an RDC although I haven’t looked at it in a long time.
So changing the length should be easy if you need to do that - just cut the frame and drill a new hole for the dead truck, if I see that correctly. You just need to see how the Athearn body fits over that frame. The dremel might be useful here. You might also have to glue some angles on the Athearn body if it is too wide.
As for DCC, I can’t see how that would be a problem. The version I saw seemed to be DCC ready. If not, you can easily hardwire a decoder. You need to make sure that the motor is isolated from the power pickup wires (wheels). I’m guessing it already is if you cut the power leads on the motor. You can test that with an Ohmmeter - just touch the motor and see if there is resistance between the motor armature and the wheels. If there is no conductivity, then just install the decoder as instructed by the manufacturer (red and black wires on power pickups, orange and grey on the motor leads, blue-white-yellow for the lights).
One improvement to the old Proto RDCs is to remove the diode bridge that is used for constant lighting , replace the headlight bulbs wit LEDs. There is a voltage drop to the motor because of the diode bridge. this will increase the speed by about 10 MPH. Beyond that aremotor with an higher RPM might help.
Really? I would like to see a picture of the inside of a geared RDC from Athearn produced in the 90’s. I worked in the business and have never seen such a thing.
RDC production stopped for many years during the 80’s, then there was one last run in the mid 90’s - flywheels added to the motor, still rubber band drive, at only $23.50 each.
The story is that during that last run, there were problems with the tooling that prevented future runs without retooling which Athearn simply was not going to do. The plastic version of the RDC came out late in 1957 and there was a metal gear drive version before that.
I don’t want to hijack this thread so I’ll answer briefly. After disassembling the shell, submerge and soak it in either 91% Iso-alcohol or the purple “Super Clean”. Message me any time if I can be of assistance.
Hi Ed! I owe you an email – your Mamiyas and I are getting along swimmingly!
All this talk of RDCs has got me thinking… and shopping. A Proto 1k with sound sure sounds neat. Does anyone know if the newer DCC-ready units are any quicker? And to they have the voltage-drop issue mentioned below?
