because i make my own track, my switchpoints tend to need alot of effort to move. i have used older twin coil type switch motors like kemtron or nj, but those are no longer made. the tortoise, made by circuitron, has the power i need and is ultra reliable as well.

as important as the brand name is the type of switch motor. i prefer those that mount under the table. they are a bit more work to install, but look much better

part of the problem is that for some reason, digitrax command stations do not like lenz based decoders like the ones in the bachmann locomotives. i have a digitrax zephyr which can read back cvs while on the programming track. it is hit or miss with programming lenz type decoders. i have tried the workaround solution of a 1k ohm resistor across the rails of the programming track but it is still hit or miss. other dcc systems don't seem to have this problem, and i now let a friend programmy bachmann locomotives for me.

the irony is that the nmra standards for dcc are based on the lenz system. why digitrax chose not to go that route is beyond me.

if i am not mistaken, 3 is the factory default address on a decoder.

quick question: is that an atlas turntable? if so you may still need an autoreverse unit as the turntable rails automaticly change polarity about halfway through the rotation. you can use an ohm meter or continuity tester to check exactly where this occurs.

athearn locomotives were about the most reliable in their heyday, the 1970s and early 1980s. all locomotives back then had their issues, but only atlas came close to the overall performance of an athearn. they are simple to work on, durable, and seem to have 9 lives....ernst made a regear kit for them which slowed them down to about 40 scale mph. like i mentioned before, they were the backbone of my fleet at one time, most of the other makes i owned were parked i liked the athearns that much......

i think it says alot that:
1. athearn locomotives are still running after 30 or more years of service.
2. the quality of locomotives to-day is such that older athearns are no longer considered to be among the best.
3. to this day, if you write to athearn they will send you parts diagrams for locomotives that they stopped producing years ago.
4. they still have enough value that other companies still make after market parts for them.
5. the overall design was sound enough that walthers, stewart, lifelike and possibly others produced locomotives on athearn clone drives. the parts from these were interchangeable with athearn....

my dad and i ran the wheels off our respective fleets, and they sure earned their keep. i also worked for a time for a model railroad display and the athearns we had ran for about 10 hours a day 7 days a week when we were set up. we were constantly repairing other makes, while the athearns ruled the road.....

i agree that the handlaid ones are the cheapest. it isn't hard to make your own. in fact, my cost of materials is well under $5 apiece. if you intend on building a sizeable number of them, you might want to invest in a jig from fast tracks.

http://www.haldlaidtrack.com

even if you don't want to buy a jig from them, they have templates you can print out on their site wich take the guesswork out of building track.....

for ties, you can buy them precut, but i make mine from matchstick, which cost next to nothing

that rusty contact bar is the weak link in the athearn drive. you can either sand the rust off it, or replace it. i usually soldered a wire from the contact on each truck to the motor clip. if you do this, be sure you remove the motor clip from the motor before soldering to it, and also be very careful when you remove this clip as there is a spring underneath it that likes to fly across the room. lose the spring, and the motor doesn't run until you find it.

since i once had a fleet of probably 40 older athearns i can help here....

first, when you move the flywheels you are also turning the motor, and the worm gear that powers the trucks. you should notice the locomotive slowly move as you turn the flywheels. if not the flywheels are loose. but you'd have been able to hear them rattle after you stopped the engine if they were.....

the biggest flaw in the athearn design is/was the electrical contact between the wheels and motor. one side of the circuit consists of the metal bar above the worm gear on the trucks, and a spring steel contact bar that clips to the top of the motor and should rub the metal bar on the trucks. the other side of the circuit comes through a metal tab on the trucks that serves as a bolsteror pivot point, the weight of the metal frame is supposed to be enough to provide good electrical contwact but doesn't always live up to its promise. the bottom clip on the motor has tabs which also contact the locomotive frame.

you will want to be sure all of the above are in contact with the parts they are supposed to contact, and clean.....

to disassemble an athearn truck you must first remove the truck from the frame.....start by prying loose, with a small screwdriver, the plactic clip covering the worm gear on the top of the truck. remove this, and the worm gear adn set them aside. be careful of the metal bearing and thin washer on the worm gear, these can get lost easily.....

next, you should be able to lift the locomotive frame clear of the truck. once clear, examine the truck closely. there should be one or two small plastic clips on top that hold the truck together, along with a much larger one on the bottom whichruns the length of the truck between the wheels....remove those and set aside.

at this point your should be able to tell if you have inside or outside bearings in the truck. if it is the later inside bearing truck, you will be able to see two vertical metal plates on the truck. the wheelsets ride in slots in these plates, with square metal bearings similar to the ones on the worm gear. if you have this type of truck, the wheels should come right out.
if you have the outside bearing type, the truck sideframes will be metal. you will have to carefully seperate the truck halves to remove the wheels.

once the wheelsets are removed, check each one to be sure they are snug in the axle gear. if they are not that's where your problem lies. replace that gear......

the jerkiness you describe sounds to me like your locomotive has dirty contacts as well. polish them with a very fine sandpaper or emery board, being sure to keep any dust out of the gears. at this point, i usually make some modifications like hard wiring the motor. if interested in this let me know and i'll tell you how i do this. also, the athearn wheels are made of sintered metal, and tend to get dirty quickly. replacements are available from jaybee and nwsl, both types are nickel silver or nickle plated and drasticly improve wheel contact with the rails.

you will also want to take the time to lube your locomotive while it is apart....

reassembly is the reverse of disassembly....

here is what i remember, supplemented by what my research on emd locomotives shows.....

the most common as built configuration for f units in general was a-b-a. many roads that bought fts in a-b sets often went back to emd for single a units to make 3 unit sets. usually, these were f2 or f3 models. i do not believe emd sold single fta's, but they did with all other f unit models.

many ft a-b sets had a drawbar between the units, as such they stayed together pretty much for life unless the railroad modified this drawbar or replaced it with couplers. very few if any other f units models came with drawbars....

the ft's were for the most part, traded in early on gp20s or gp30s, by the end of the 1960s they were all but extinct....the other f units lasted on certain railroads until the early 1980s, which are the ones i will base my personal observations on.....

i was fortunate enough to catch the f units in service on the b&o, western maryland, penn central/conrail, and the clinchfield. at this late date, they were considered just another locomotive and were mixed freely with other types. by this time, b units were relatively scarce, as the railroads found their lack of a cab to limit their usefulness.

it should be noted that other builders locomotives were not always compatable with emd. the baldwin sharks, for example, only ran with their own kind. only the b&o mixed them with other baldwins on a regular basis.

some alco fa's and fb's could be used in multiple with emd, but these seem to be the exception rather than the rule.

a more likely cause of the athearn wheels turning by hand, assuming both wheels are on the same axle, is a cracked axle gear. this was a huge problem in proto2000 units which used parts comapable with athearn. athearn's axle gears are usually more durable. what happens is the gear is force fit on the wheel and axle halves. sometimes they split when this is done, or after they've been run for a while. replacement gears were readily available though i haven't bought any in years.....

when you say the locomotive barely runs at all, what exactly do you mean? is the motor sluggish? does your unit run jerky, stopping for no apparent reason?

cne
i agree that the kadee centering springs can be a pain. kadee now offers a #148 whisker coupler which eliminates this spring in favour of metal whishers on the side of the coupler shaft.it makes them a drop in replacement like the plastic knuckle couplers.....

replacing the older horn hook couplers on your cars isn't as simple as a drop in replacement, especially with truck mounted couplers. with knuckle couplers, coupler height is critical and i STRONGLY urge you to get a kadee coupler height guage and use it..... minor differences in coupler height can be fixed by raising or lowering the coupler box.

your cars with truck mounted couplers present a much more complicated problem. first of all, you'll probably want to have your couplers mounted on the body not the trucks. they are much more reliable that way, especially when backing up. second, even if you do opt to keep the truck mount, the couplers are often too low and the trip pins catch on trackwork, not to mention that mismatched height leads to cars uncoupling where you don't want them to.

probably the best interim solution for you is to make a "conversion car" or two. you take one of your cars with body mounted couplers, and replace one of the knuckle couplers with a horn hook. thus, you can have your locomotive and knuckle coupler cars ahead of this car, and your horn hooks behind.

last, the comment was made that kadee couplers are the best. i concur, they are metal and very durable and should last a lifetime. that said, i generally leave the other makes of couplers in place until they fail before i replace them with kadee. most if not all knuckle couplers will work with kadee so compatability should not be an issue.

one final note on block wiring. by replacing the toggle switches with rotary ones, it is possible to have even more than two cabs. the basic principle is the same, track feeders to the center contacts, your various power packs to the outer contacts. just remember to keep the locations of the wires from each pack the same on each switch, and to leave at least one position unconnected so you have a way to turn off power to that block. also, there are two varieties of rotary switches, shorting and non shorting. the shorting onesconnect adjacent contacts momentarily while they are being switched, which causes all sorts of interesting problems because you are actually connecting your power packs together for an instant. use the non shorting ones and this will never be your problem.

bob,
i feel the purpose of these boards is to share information. we all come from different backgrounds and thus have different knowledge to offer. i personally have been impressed by your knowledge, and the overall tone of the posts here. unlike some other boards, everybody is respectful here. it really helps when we all have access to this kind of knowledge....

thanks for being an integral part of it.

30 years ago, i had modelled several gp35s with aar type b trucks from athearn units. the type b sideframes as used on the u boats were interchangeable with the blombergs under the emds. somebody also made sideframes of the more modern ge fb-2 truck, which also fit the athearns. so you could model later u boats on fb2s, and gp35s on type b's.

i was unaware of the difference in wheelbase between the type b's used under baldwins (with westinghouse motors) and alcos (wit ge motors).......
i believe all the gp30s and gp35s that rode on these trucks had alco trade ins, so maybe the baldwins longer wheelbase made them unusable?

thanks everybody for the replies. i learned something new to-day....

yes. and it can be as simple as plugging a decoder in to a recepticle in your locomotive. older locomotives often require custom decoder installation.
for an example of a custom installation, on a bachmann diesel with the split frame, follow this link:
http://members.shaw.ca/sask.rail/dcc/tmaster/tmaster.html