How common are conductive wheel sets?

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cpsk

New Member
Hi;
I am curious to know how many modelers use DCC and conductive wheel sets, and whether you modify your own rolling stock or buy the conductive wheel sets.

Thanks for your input

FW
 

MGWSY

Active Member
Hi;
I am curious to know how many modelers use DCC and conductive wheel sets, and whether you modify your own rolling stock or buy the conductive wheel sets.

Thanks for your input

FW

I am planning to modify the outer axles on all my cars eventually and due to the different axle sizes it would prob be better to just add resisitors yourself. All you would need is a bunch of Surface Mount Resisitors in a value that your detection system recommends, Some Glue to glue the resister to the wheel, and some conductive paint to go from the resistor to the metal wheels. I Mainly use intermountain wheelsets and they have one wheel that has the insulated center hub. So you just glue the resistor to the plastic wheel hub and paint traces to the axle and wheel tread. Check out the following two links.

http://www.allpointsnorthmrrc.org/files/tech/resistors.htm

http://www.tslrr.com/detector.htm
 

cpsk

New Member
I assume that if you're using 1/8W resistors their weight is not going to be enough to throw off the balance of the axle-wheel set and cause problems.
I think I have read that some use two resistors of half the required value, one on each wheel, so there is no imbalance.
If one were going to use the two resistor method, then the isolated wheels would have to be used on both sides, not just one like you indicated.

Let me go one step further:
Let's say you're using DCC for all your locos. So you don't need to use isolated blocks for that, but still need it for signaling, right?

Prototype RR's are using a system which does not require isolated blocks for signaling or grade crossing circuits. I understand that this system uses a signal traveling through the rails, and some sort of phase detection to determine whether a train is within the signaled "block" or not.
Has anyone come up with such a circuit for model RR's?
It would surely simplify the process of building and maintaining a large layout.
This type of circuit may or may not require different resistor values in the cars though...

FW
 

MGWSY

Active Member
I assume that if you're using 1/8W resistors their weight is not going to be enough to throw off the balance of the axle-wheel set and cause problems.
I think I have read that some use two resistors of half the required value, one on each wheel, so there is no imbalance.
If one were going to use the two resistor method, then the isolated wheels would have to be used on both sides, not just one like you indicated.


Nope they won’t do anything to the balance and yes both wheels would have to be insulated or have a plastic insulated axle. I have seen people drill holes in the wheels and put a regular resistor between the wheels along the axle. Also people have done something similar between both axles in a truck like here.

http://www.teamdigital1.com/applications/tech_talk/resist_wheel.html

Let me go one step further:
Let's say you're using DCC for all your locos. So you don't need to use isolated blocks for that, but still need it for signaling, right?


Correct you would still need isolated blocks with detectors for signaling in each block. Some systems are self contained to fully computer operated CTC setups.


Prototype RR's are using a system which does not require isolated blocks for signaling or grade crossing circuits. I understand that this system uses a signal traveling through the rails, and some sort of phase detection to determine whether a train is within the signaled "block" or not.
Has anyone come up with such a circuit for model RR's?
It would surely simplify the process of building and maintaining a large layout.
This type of circuit may or may not require different resistor values in the cars though...


Actually Real railroads do use insulated joint bars for signal circuits, grade crossing circuits operate as you mentioned with a phase detection that detects trains at different speeds. If you go to a signal location you will find insulated joint bars in the area to separate the blocks.

In the following picture you can see the insulated joints on both tracks close to the signals. The rest is welded rail.

http://mgwsy.smugmug.com/Trains/2282011/16019730_9C6ZnD#!i=1226490158&k=mvpvs&lb=1&s=X3

Here is what an insulated rail joint looks like up close.

http://farm4.static.flickr.com/3347/3478244151_f0d8c9e7e9.jpg
 

cpsk

New Member
Before CSX took over the Conrail mainline in my area, I used to walk along the ROW, and found none of those joints at signal locations or grade crossing circuits. It was a puzzle to me, until I figured out how the circuits could work without insulators. It gets somewhat complex, and I am not completely sure of the circuit design.

I can no longer get close enough to the track with CSX cops all over, and very intolerant of railfans, especially if I were to be inspecting track that closely.

I'll see if I can get more info on the newer circuit.

FW
 

MGWSY

Active Member
Before CSX took over the Conrail mainline in my area, I used to walk along the ROW, and found none of those joints at signal locations or grade crossing circuits. It was a puzzle to me, until I figured out how the circuits could work without insulators. It gets somewhat complex, and I am not completely sure of the circuit design.

I can no longer get close enough to the track with CSX cops all over, and very intolerant of railfans, especially if I were to be inspecting track that closely.

I'll see if I can get more info on the newer circuit.

FW

Are you sure that the Line didnt have Cab Signals for the locos and Just signals at interlockings as that could be a reason? If the Signals had a little seperate single light signal with a C next to the light then the line had cab signals which display inside the locomotive or was the line ABS? I know up where I live near the Boston Line there is still a mix of insulated joints at interlockings and the RR I work for still uses insulated joints too. In the picture I posted which is Amtraks Springfield Line from New Haven CT to Springfield MA you can see the joints near the signals. Usually in welded rail teritory the RR would weld in a section of rail with the insulated joint already together. so you would have a short section of rail around 20ft that would have a weld - insulated joint in the middle - weld. I have no clue why they do it that way but thats one way I have seen it done.
 

cpsk

New Member
Are you sure that the Line didnt have Cab Signals for the locos and Just signals at interlockings as that could be a reason? If the Signals had a little seperate single light signal with a C next to the light then the line had cab signals which display inside the locomotive or was the line ABS? I know up where I live near the Boston Line there is still a mix of insulated joints at interlockings and the RR I work for still uses insulated joints too. In the picture I posted which is Amtraks Springfield Line from New Haven CT to Springfield MA you can see the joints near the signals. Usually in welded rail teritory the RR would weld in a section of rail with the insulated joint already together. so you would have a short section of rail around 20ft that would have a weld - insulated joint in the middle - weld. I have no clue why they do it that way but thats one way I have seen it done.
No cab signals on this line. It's freight only, and only 50mph max.
Here is a link to one company that makes the circuit I am talking about.
http://alstomsignalingsolutions.com/OurProducts/WaysideProducts/TrackCircuit/DualCodeTC/

FW
 

MGWSY

Active Member
OK must be a new system they are installing. Probably to comply with the PTC requirements in the future. I have seen systems like this for multiple road crossings in a small area and each crossing would run on a different frequency with no insulated joints throughout the circuit. So that’s probably what they are installing now on new signal upgrades. As for doing something like that on a model railroad I am not sure it would work well with DCC signals going through the rails but I am sure something could be made but it would most likely cost a lot more then regular block wiring.
 




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