A Resurection of Sorts

CNWman

CNW Fan
Wow, it's been a while, but I'm back, and once again I'm in need of some help with my trains. A long time ago, I purchased a TYCO Chattanooga 638 2-8-0 and I asked if it was worth working with: http://www.zealot.com/forum/showthread.php?t=163494

Well, a little over a year and a half later, that engine is now torn apart and is in pieces, awaiting the day that I stop procrastinating and get it running again. So far all I've really done is remove the smoking mechanism, which looked like it should have been disposed of years ago, and the wires are all disconnected so the tender-drive doesn't work anymore (it hardly did, anyways) but all the other parts are still around and I need some help with what to do from here.

Namely, I need to remotor it, the new motor being mounted in the actual engine boiler (like any decent modern steam engine), and with that I've got a whole list of problems associated with it:

-What are the specific specifications of the new motor? (I hear NWSL's motors work best for repowering TYCO's, but there are so many measurements that necessitate different engines that I don't know where to begin)
-How will the drivers be reworked so that all four driver axels are working?
-How can I retain the old "boxy" tender but scrap the worthless tender drive and install a DCC set-up in it that's wired to the front motor?
-How can I modify the front truck to not derail every time it hits a switch?

Any help at all will be appreciated, and I'm willing to try alot since I'm not loosing a whole lot if this project goes south.
 

Bill Nelson

Well-Known Member
don't fear the tender drive!

The disadvantages of a tender drive mechanism are greatly exaggerated by a bad motor I have four tender drive locomotives on my active roster, and several on the work bench.

Two of the ones in active service are Hon3 FED Spartans, a 4-4-0, and a 2-6-0. both of those have been remotored with kits from Loco Doc , which replace the almost 40 year old open frame motors with precision micromotors with flywheels. The electrical pick up is also improved. This eliminates the tender rocking form the tourqe of the fast starts you get from the cheap obsolete motor. A horrible electrical path has been redesigned on both locomotives, and they run as well as any HON3 brass I have ever seen, although they are noisy. (new they cost $38.00 when most HON3 brass ran from $125 up)

I also have two Mantua Generals, one of which has a Cary boiler, which updates it to a 1930 style American, and the other has the original 1860 boiler. The latter has had it's entire tender , motor and all, replaced with the tender from an AHM Genoa. the previous one had it's tender replaced with a MDC tender , which I milled a big grove through the Zamax tender frame to allow a motor from a Cannon Copier to fit in there. The Modern 4-4-0 runs flawlessly, and the 1860's locomotive runs ok, but it has lost some traction tires to extreme old age and clunks and bumps on the grooved drivers.

Putting the motor in the locomotive proper will be a lot of work, and the locomotive will pull more if any space on it is filled with lead. Much easier to put the motor in the tender. modify the locomotive so you get electrical pick up from as may wheels as possible. and if the drawbar is sloppy, allowing lots of tender rock, modify it or replace it to stabilize the tender.

With a good motor, and good electrical pick up; there is no need to fear the tender drive. It allows a bigger motor, and a larger motor will run smoother. also a better motor will have a slower bottom and top speed. If you like slow running locomotives consider a gear reduction motor.


Bill Nelson
 

Bill Nelson

Well-Known Member
front truck question

there are two approaches, but first check the wheel gauge againt an NMRA standards gauge first to be sure that the wheel in properly gauged. Be sure that the axle rolls freely in the front truck, if the wheel is skidding instead of rolling it will not track well.

Be sure the screw holding the front truck on isnt too tight ot too loose. Some Tyco/Mantua locomotives have leading and trailing trucks with round ounched holes in them the holes have a lip that holds a conical spring in place . If that spring is missing, the won't track worth a flip. There are some ways you can add some spring pressure by modifying the lead truck with a little phosphor bronze wire to center the truck and add some down ward pressure on that front axle.

I am not familiar with this particular model, if you can post a picture of the front truck I may be able to make more specific suggestions. I have a Tyco 2-6-0 one of the guys at my club picked up at a yard sale for $5.00. It needs a new motor so it will be happy with DCC. Surprisingly it's open frame motor runs very well on DC, after it got a shot of tuner cleaner on the armature.


Bill Nelson
 

pgandw

Active Member
The disadvantages of a tender drive mechanism are greatly exaggerated by a bad motor I have four tender drive locomotives on my active roster, and several on the work bench.

Bill Nelson

Bill

The issue is that the entire drive is contained in the tender, not just the motor. There is no gearing or gearbox in the engine. I have the same issue with my Model Power (made by Frateschi) 2-8-0.

As the responses in the original post suggested, the easiest route is going to be using a GE 44 ton or similar drive (Keystone Shay, MDC Shay, MDC Climax, MDC boxcab), again keeping everything in the tender. Good points of this approach are no modifications needed for the engine. The tender becomes a small diesel mechanism with a steam tender body. Downside is finding a mechanism with a small enough wheel base to suit your tender trucks. Also, most drives will need some shortening to fit in the shorter space of your tender. Finally, your engine drivers will not spin under load because they are never powered.

The more difficult road is to fit a gearbox in the engine. I am assuming the frame, drivers, and side rods are metal, and will withstand the loads of transmitting power. On my Model Power, the engine is all plastic, and cannot be powered. To power the engine, I am looking at using the Model Power superstructure on a Tyco Rogers 4-8-0 or MDC Old Timer 2-8-0 kit mechanism. Doing something similar may make more sense than trying to fabricate a mechanism.

The motor can go either in the engine or the tender, as Bill explained. NWSL sells suitable gearboxes - you will probably want a 27:1 or 37:1, depending on motor RPM and how fast you want the model to run. You will need to remove the side rods and other linkage, cut the frame for the gearbox, remove the uninsulated driver on the chosen axle, install the worm gear, requarter the drivers, and reinstall side rods and valve gear. Test at each stage to make sure everything is moving freely without being sloppy. Then you will have to fabricate a suitable motor mount and shafts and universals to power the worm shaft in the gearbox. Finally, to pull and track decently, the weight of the engine needs to be approximately balanced over the center of the driver wheel base.

As was said in the original post, this was not a great model locomotive to begin with, and is not worth much. You will spend time and money to make this run well - more than the model is worth monetarily. That's not to say the project isn't worth doing. If you enjoy the work, and really want to see that engine run well, it's worth it. If not, call it good, and leave it in a display case for sentimental reasons.

my thoughts, your choices
Fred W
 

Bill Nelson

Well-Known Member
Ok, I think I understand now. Putting gearing on an axle to power the locomotive will be a massive and difficult job. If you replace the power for the tender with a better running mechanism, it is only going to be easy if the mechanism is close to the right size. It seems to me that it won't pull real well unless the locomotive is very free rolling. If the donor mechanism is too long, using a longer tender might be easier than cutting the mechanism down.

Weather this is worth it depends on how much time you have, and how many other projects you have in the works. I don't know what this locomotive looks like, but it seems to me that this project will only be worthwhile if it results in a superbly running locomotive.

Over the years I have come to the conclusion that one excellent running locomotive is worth a boat load of poor or mediocre running locomotives. When it comes down to looks and performance looks are only going to win for me when performance is close.

Is it worth it to you? that comes down to an estimate of your own time and treasure, and an estimation of the results. I will admit to wasting a lot of time with balky mechanisms, but most of those either had great sentimental value, were brass locomotives that looked really good, or were MDC mechanisms, which promised a lot of pain while working out the kinks, but had the potential to become excellent runners, although looking plain.

Some locomotives are best spray painted with red auto body primer and flat black simultaneously to give the the look of rusted heaps to be parked out on the scrap line behind the engine house.


Bill Nelson
 

Bill Nelson

Well-Known Member
This project is one that doesn't have a lot of upside. with steam locomotives you are much better off making cosmetic changes to a good mechanism, or replacing a motor on an otherwise good mechanism. Building up a steam locomotive mechanism from scratch would be a long hard project, and frankly this locomotive isn't worth it, unless you have a great emotional attachment to it. Back in the good old days there were a variety of steam locomotive kits, Bowser, MDC, Mantua that could be raided for their mechanisms. today locomotive kitbashing is more expensive, as we generally have to start from more expensive ready to run locomotives, or yard sale locomotives.


Modifying the existing frame, adding gears, re-quartering the drivers, and fitting a motor to a drive train is going to be so difficult you might as well be scratch-building a steam locomotive. a worthy endeavor, but entirely too much work to put into a mediocre looking model . admittedly with some cosmetic work, carving off some cast in detail and adding some castings, you could improve the looks of this considerably, but doing so would be, to quote my former crude co-workers in automotive repair "Polishing a t**d".


The only easy way to do this would be to get a small diesel (look into the Bachman GE 70 0r 45 tonner I converted a 70 tonner to Hon3, and it is small, has a good mechanism with all wheel pick up, and comes from the factory with a dual mode decoder installed. The trucks have relatively small drive wheels. The side frames are removable, but I would leave the stock ones on, as they serve as retainers for the electrical pick up. I was able to pick mine up on sale for about $60 that is a good deal when you consider it comes with a decoder installed.

If you want to try to build an entire mechanism, the NWSL motor measurements are in millimeters they list the motor circumference, length , shaft diameter, and shaft length. re-motoring an otherwise good mechanism can be tricky for me , and I've been doing it for 40 years . I have built a Geared locomotive drive train from the frame up, but a rod locomotive is much trickier. I'd recommend finding a locomotive with a good mechanism, and starting from there. If you seriously want to resurrect this locomotive I'd look into putting a Bachman 70 tonner mechanism under a tender shell. anything else is likely going to be more pain and suffering than this plain model is likely to be worth.



Bill Nelson
 
Top