Question: Walthers Passenger Trucks/Wheels

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R

RexHea

RAIL BENDER
I gave myself a bit of a problem:
I shortened a reversing loop to accommodate a detection block in the loop. By doing this, I had to remove the interior lighting of Walthers passenger cars so the reverser wouldn't go bonkers and finally short when the loco was half out of the reversing section when a passenger car wheel crossed the gap

After testing a train in this newly configured section, the first passenger car caused a short when crossing the gap. At first this was puzzling, but then I remembered that a Walthers car truck was conductive for the light pickups. I had one wheel before the reverse section and one in while the engine half in and out. Now the reverser doesn't know what to do so it breaks the circuit.

Now the question: I have to either replace the trucks with some that are not conductive at a huge cost or find some wheels (other than plastic) that are not conductive (best). Do you have a suggestion or know of any 36" wheels that will not conduct electricity?

Thank You.
 
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the Proto 2000 wheels I got come in 33'' and 36''. they are metal wheels with plastic axles, would that do it for you Rex?
 
Thanks Jerome, but the problem is not from the wheels through the axle. It is the wheel picking up the track power and transferring it to the truck by the axle point in the journal. Is the axle tipped with plastic or something non-conductive... that would work.
 
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Passenger car shorts

Josh is right. I have 16 of these cars and the axles are plastic but if you have lights in the cars then it becomes a problem and a short may occur. Otherwise with out the lights the circuit would be open. I’ve noticed with my cars that they easily short the switch frogs maybe because of their length forcing the wheels to touch both tracks on the frog. Painting all your frogs with nail polish or something would solve that problem.

NYC_George
 
Truck trouble

Now I see what your saying Rex. I see there’s some side to side play in the axle so I guess at some point both sides of the axle touch the metal truck at the same time causing the unit to trip. I thought the trucks on the first cars made were metal but the second group I thought had plastic. I have both. After I come back from my mother’s house I’ll go down stairs and do some testing.

NYC_George
 
Thanks George, I would appreciate that.Yeah, the truck is metal and the pickup for the lights is in the middle of the car, using screwheads on a metal strip.

Josh: If the P2k axles are plastic and all the way through, then that is what I need. It's only the tip into the truck that I need insulated.

I know this wasn't written very clear, let me try again using only one truck and one side:
The pass. truck is metal. When crossing a gap on one rail, the rear wheel is on the main rail and the front wheel is on the reversing rail, short. Normally, this is not a problem and would just simply reverse or adj the polarity. However, if the loco only has its front truck or wheel out of the rev. section at the other end, the reverser doesn't know which way to switch the polarity: for the loco or for the passenger car. This would also happen between the passenger cars: one entering while one leaving.

This is why you should always have a reversing loop/wye the length of a lighted train. Then the whole train would be in the section and you would not get the ping-pong effects. On a short reverse section (little over longest loco), you could experience this same problem with a caboose and resistor wheel, but most likely the loco would be well out of the section before the caboose entered. If all the cars had resistor wheels: YIKES, same problem.


Now I'm sure you are thinking, "Why the H is he shortening a reverse section when it works fine as is." For sometime now, I have been installing detection sections using Digitrax BDL168 boards (each incl.4 groups of 4 detectors =16). The wiring requires that a reverser feed the track power to 1 group on the board, not just a single. (If connected from the board to the reverser and to one section, the reverser would be seen as a load and always show occupancy.) I only need one detection section, so 3 detectors would be unused. I am trying to avoid this waste by simply not using the shortened reverse section in the detection. At about $8/detection, I would be saving $24. Now, that is not much by itself, but it would cause me to buy another board and use only part of it to replace the 3. Now that is $125 plus the $24.
 
Plastic side frames

Well Rex I looked and found that the ones I bought first were with the plastic side frames the ones after that were metal. The Walther’s part number for the truck is 933-1046 Superliner Bud or Pullman streamlined passenger cars with plastic side frames and 36” metal wheels. I guess that would solve the problem but maybe not. I can't find my voltage tester right now when I find it I’ll get back to you.

NYC_George
 


The problem with Walthers passenger cars and reverse loops is that the trucks pick up from both sides at once. Both sides of the truck are "hot", which doubles the number of wheels picking up for better lighting, but it means when you cross a reverse loop boundary, you have a short.

If you have already given up on the lighting, then you can replace the wheelsets with something with plastic axles like Proto or Kadee.

If you want to keep the lighting but only have 4-wheel pickup, you could do this by removing the pickup contact on one side at each end of the car. The screws on top of the truck contact a metal strip. Remove the strip on one side at one end, on the other side at the other end.

Andy
 
Uncommon electrical problem

This is Rex’s problem but that doesn’t solve it. It seem that at some point both the outside metal wheel journals touch the metal truck at the same time that has no insulation between the two half’s to protect against this type of short. I guess it’s so minor that the DCC unit doesn’t pick it up but the reverse loop detection does. Even if you took out all the contacts it would still cause the short. I have to go find my voltage tester so I can see what’s going here.

NYC_George
 
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Test complete

Well Rex I just went down stairs and tested both trucks. What you’re saying can’t happen because the bridge between the two half’s is plastic, although it looks like metal. So even if the two metal wheel journals touch the truck at the same time there’s no way for the current to jump to the opposite side frame. The other trucks that I said were plastic are only plastic on the outside frames, metal inside.

NYC_George
 
Rex
im not sure if this helps but I hear if you stagger the gaps in the rails going into a reverse loop it helps the DCC reverser reduce shorts caused from metal wheels.

Has anyone heard about this?

Trent
 
Andy, I have already removed the lights and will keep them out. They were drawing around 1 amp for five cars and although cool, they have been more problematic than fun to work properly.

It's not the left car side of the truck shorted to the right car side truck.

George, using the metal truck measure between the two wheels on the same side and you should see a short. Another thing to help you see what I'm saying is if you have a reversing section, place one lighted car half in the section. Take another and slowly roll it in from the other end. It should show the same effects that I have described.

The two truck wheels per side are electrically common to each other on the same side via the truck being metal, ie a short. So, when one wheel in the rev section and one wheel before the section. This is sensed as a short to the reverser and it changes the polarity.

As said, this is fine except when the loco is half in and half out of the section at the same time, then its power is trying to switch on the back trucks while the front trucks are in a different polarity. I need to have the reverser only change as a result of the loco.

Trent, yes I have heard that, but all it takes for a reverser to work is a short across the gap on one rail. It senses a short because the polarity is opposite on the other side of the gap. If the polarities match, then there is no short and no need to reverse.
 
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Rex, sounds like an insoluble problem as long as you're drawing power from the trucks. I think your best option would be one of the new LED light kits that runs on batteries to light the cars. I've seen a few in operation and the light was much more realistic than the brighter incandescent bulbs and no flicker across rail joints either.
 
Thanks Jim, but I don't mind not having lights. They're nice but I would rather work out this reverser problem. I have about 6 or so, Kaddee passenger wheels and I think that I will try them and see what happens. I don't read continuity from the wheel to the axle, but that may be just the paint. Can't tell what the axle is made of. Guess I need to look it up.
 
The Kadee website says the 36" smoothback wheelsets have insulated needlepoint axles so they may work for you.
 
Gotcha Rex...
sounds like one of the issues is that the reverse loop section is to short to fit the intire train into? thus messing with the lights and shorting out? I have a simmilar small reverse loop section but I only run 2 locos max no lighted cars
 


I just tried 2 pair of the Kaddee 521's that I had a few of and they worked great. Jim, that is the same as the smooth back only ribbed. I will order a batch of them unless one of you guys has a better brand.

Yes Trent, the shorter rev section is the root cause. The lights had been removed, but I still forgot the trucks were metal and that the backwheels would conduct the electricity through the truck to the front wheels on the same side. This is nothing until you cross the gap and then the front wheel is on one side and the back wheel on the other = reverse. Still not bad unless you have an engine half in and half out of the rev section other end. Then SHUTDOWN.

I had to shorten the reverse section in order to use a detector in the remaining track loop. This allows me to save three detectors for somewhere else, but detect everything in that loop except the shorter reversing section. That won't matter that much because it is relatively short.;)

Let me know if I should order anything better/different! Also, if there are any questions or thoughts.

Thanks for all the good input to this thread. :)
 
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