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Losing my patience with endless technical bugs

Started by H5subway, August 09, 2024, 05:12:28 PM

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H5subway

Lately all my trains except one have been stalling and stuttering randomly for no apparent reason, some more often than others. Yes I would clean the track and the wheels before running them, yet the same problem could still occur even right after cleaning. Some problem spots on the track I would vigorously scrub by hand with alcohol, and recently I caved in and bought a track-cleaning car to do the work for me by having a locomotive push it around the layout at max speed. Unfortunately, that's not 100% effective either. The problem is worst when running at slow speeds, although sometimes even at max speed a train might suddenly stop and start again, for no reason at all, on a continuous section of track that it went through without issue the previous time. And often a train might inexplicably lose power if positioned in a particular way no matter how clean the wheels and the track are, which is what usually results in sudden stalling at slow speed.

I put together a 2-minute video compilation to better show the bugs I'm dealing with: https://drive.google.com/file/d/1uRaQdCGrLC7onssxM5xRk_D03UICTzV8/
(that's a brand new GE 44-tonner btw, which shouldn't have those issues right out of the box)

My layout also has 2 reverse loops, with the reversing sections forming an X, and some trains would often trigger the autoreverser when passing through the middle of the X at slow speed, while the entire train is fully within the reversing section, even though there should be no way for the train's wheels to cause a short or anything (this problem is also included towards the end of the video, where the clicking sound can be heard while a train crosses the X, or even when it's stopped there, when gently tapping it would do the trick; the exact position of the train's wheels is shown in the last 2 slides of the video). Both reverse loops used to use Bachmann autoreverse modules, one of which has since been replaced with an MRC AD520 autoreverser, which seems to be more reliable thus far. I just received the second MRC AD520 today, to replace the other Bachmann module, which will hopefully solve this problem.

At this point, I'm thoroughly convinced that having trains powered by the running rails is an absolutely terrible design, and how much better, simpler, and more reliable it would be to simply have each train powered by batteries and operated by a remote control, allowing them to run much more freely and autonomously (you could even take them off the track and run them on the floor if you felt like it!). Not to mention, nothing is more unprototypical than trains being powered by the running rails. The closest real-world example that comes to mind are rapid transit lines that use linear induction motors & reaction rail technology (and having had one of those in my city, I can say those trains definitely couldn't move as freely and smoothly as regular 3rd rail / overhead wire / diesel trains can; not to mention that they couldn't run at all whenever the reaction rail was covered in snow/ice, much like model trains can't run properly unless the running rails are spotless).

jward

The biggest problem you have is that you are trying to use steel rail track with DCC. Steel rail is very hard to keep clean, and DCC requires clean rails for an uncorrupted control signal. If you look at the Bachmann catalog you will see that all DCC sets come with nickel silver rail. There is a good reason for this: conductivity is much better with Nickle silver and is requires far less cleaning.

Exacerbating your problem is the short wheelbase locomotive running over a switchpoint that's making intermittent contact. A longer wheelbase locomotive would help solve the problem as it would bridge the dead spot better. My solution in a situation like this is to solder a feeder wire to the dead switchpoint, but that is impossible to do with steel rail.

A third problem appears to be the wheels are coming in contact with the cross rails at the crossing. this bridges the two seperate circuits I assume you are using on this crossing as you referred to using two different autoreverse units. Your wheels are completing a circuit between the two autoreversers as they are wider than the insulated parts of the rail at the crossing. A simple solution is to paint the rail meatl rails at the crossing with clear nail polish, just enough so that the autoreversers don't trip.


As for battery powered dead rail. Yes it is a solution, but it is expensive and a pain to install. Two rail power is a time tested method of controlling the trains, in widespread use longer than most of us have been alive. That you disregarded recommendations of the manufacturer by going the cheap route with steel rail, then trying to run DCC on that track in no way means that the control system is at fault. If you want things to work right, you have to design and build your layout using the recommended components. That you did not do so is YOUR fault, not the manufacturers.
Jeffery S Ward Sr
Pittsburgh, PA

trainman203

#2
That is a very well stated thorough and analyzed response, Jeffrey. The only thing I might add would be that the problem you describe in item 3 can also occur at insulated switch frogs where a wide wheel tire can momentarily contact the two opposite polarity rails, just like as the crossing as you described.  I have that problem with long wheelbase steam locomotives at my few No. 4 switches, whose installation I regret endlessly to this very day, but the same clear nail polish treatment solves it.  I did find that it's good for several years, but it wears off enough after time to require another application. However, that's probably less periodic maintenance than a real railroad would require at  a switch.

jward

Quote from: trainman203 on August 10, 2024, 04:59:00 PMThat is a very well stated thorough and analyzed response, Jeffrey. The only thing I might add would be that the problem you describe in item 3 can also occur at insulated switch frogs where a wide wheel tire can momentarily contact the two opposite polarity rails, just like as the crossing as you described.  I have that problem with long wheelbase steam locomotives at my few No. 4 switches, whose installation I regret endlessly to this very day, but the same clear nail polish treatment solves it.  I did find that it's good for several years, but it wears off enough after time to require another application. However, that's probably less periodic maintenance than a real railroad would require at  a switch.




Thanks. I was fortunate enough to have had a grandfather who was one of the pioneers in HO scale, having gotten his start before WW2 when you had to build everything from scratch. The nail polish trick was one of the many things I learned from him. And yes, it will work on any frog.

It especially comes in handy with DCC. There are alot of momentary shorts like this on a model railroad that we never noticed on DC because by the time the circuit breakers in the power packs reacted, the locomotive was past the problem area. But on DCC the circuit breakers are almost instantaneous, and these problems we never knew we had on DC can cripple a DCC railroad.
Jeffery S Ward Sr
Pittsburgh, PA

Tenwheeler01

#4
All of my #4s have nail polish on them just for my Bachmann 2-10-0s.    In a punch when I could not find the clear nail polish I have used Strormshield or Ardcoat.

trainman203

Yeh, it's also my 2-10-0's causing the shorts at my No.4 switches.  I have six of them operating right now, with 3 in the shop, and they're my favorite engines, doing almost all of my work.  I confess, one of them is a brass engine, but it still does the same act at the switches.

H5subway

#6
Quote from: jward on August 10, 2024, 04:37:10 PMThe biggest problem you have is that you are trying to use steel rail track with DCC. Steel rail is very hard to keep clean, and DCC requires clean rails for an uncorrupted control signal. If you look at the Bachmann catalog you will see that all DCC sets come with nickel silver rail. There is a good reason for this: conductivity is much better with Nickle silver and is requires far less cleaning.

That you disregarded recommendations of the manufacturer by going the cheap route with steel rail, then trying to run DCC on that track in no way means that the control system is at fault. If you want things to work right, you have to design and build your layout using the recommended components. That you did not do so is YOUR fault, not the manufacturers.
So my layout actually consists of a mix of both steel rail and nickel silver (black roadbed & gray roadbed), the reason being I originally started with a DC starter set over 4 years ago and gradually expanded my layout, and switched to DCC just under 3 years ago. I kept using the original track I had, and bought more over time in both varieties, depending on availability (i.e. some pieces of track were only available in the nickel silver version). I'd say roughly 1/3 to 1/2 of the track I have is nickel silver, but at this point it might not be sensible to replace all the existing steel track (not to mention that the same problems could occasionally occur on nickel silver track as well).

Quote from: jward on August 10, 2024, 04:37:10 PMExacerbating your problem is the short wheelbase locomotive running over a switchpoint that's making intermittent contact. A longer wheelbase locomotive would help solve the problem as it would bridge the dead spot better. My solution in a situation like this is to solder a feeder wire to the dead switchpoint, but that is impossible to do with steel rail.
I've also figured that could've been a problem, which only highlights another deficiency of the 2-rail power system, as ideally any trains should be able to run anywhere without issue. I've thought about possibly wrapping foil around parts of the dead switchpoints to reduce the electrical gaps (basically the opposite of applying nail polish), but that could exacerbate other problems like causing shorts.

Quote from: jward on August 10, 2024, 04:37:10 PMA third problem appears to be the wheels are coming in contact with the cross rails at the crossing. this bridges the two separate circuits I assume you are using on this crossing as you referred to using two different autoreverse units. Your wheels are completing a circuit between the two autoreversers as they are wider than the insulated parts of the rail at the crossing. A simple solution is to paint the rail metal rails at the crossing with clear nail polish, just enough so that the autoreversers don't trip.
Based on the position of the train's wheels at the crossing, I really don't see how it could bridge the circuits, as all the wheels are either touching the live rail they're rolling on, or the dead plastic switchpoint, and are clearly not touching the intersecting track's live rail (the insulated gaps prevent that, as they're supposed to). In fact, I've found that the wheels on that particular car are slightly too narrow out of gauge (checked using the NMRA gauge tool) which would also explain why they'd short out at the turnout exiting the reverse loop.

It's odd though that even with 2 independent circuits for the reverse loops, they do appear to switch polarity at the same time, even if only 1 of the circuits is flipped, and attempting to flip only one at a time (by keeping the other one constant by bridging one of the insulated gaps) would just short out and reset the layout.

Quote from: jward on August 10, 2024, 04:37:10 PMAs for battery powered dead rail. Yes it is a solution, but it is expensive and a pain to install. Two rail power is a time tested method of controlling the trains, in widespread use longer than most of us have been alive.
While retrofitting existing 2-rail powered trains with batteries and remote control operation may be too difficult, I don't see why they couldn't be built that way to begin with, since lot's of battery-powered remote-controlled gadgets do exist (toy cars, drones, etc), which I find hard to believe is more difficult to implement than a 2-rail layout requiring complicated wiring for things like reverse loops, etc.

CNE Runner

It has been my experience that short locomotives can be temperamental at best. Case in point is the Bachmann GE 45 tonner. I presently own 3 of these units (1 fit only for parts, 1 ran poorly out of the box...an estate purchase, and 1 that runs like a fine Swiss watch). The secret is to install a "Keep Alive" module. My #4 (the 'Swiss watch') still has the original DCC circuit board (yes, with those ridiculous orange headlights); BUT I [had] added one of the many mini Keep Alive/Current Keeper modules. Before I had to clean the track almost daily and I still had problems. Enter the Keep Alive/Current Keeper and all those problems disappeared. I don't presently own a Bachmann GE 44 Tonner; but that could be a relatively inexpensive fix for the problem. Just saying...
"Keeping my hand on the throttle...and my eyes on the rail"

russ daley

This forum is fortunate to have you guys around...your knowledge is priceless....

trainman203

Nowhere was mentioned cleaning of locomotive wheels. 

H5subway

Quote from: H5subway on August 09, 2024, 05:12:28 PMYes I would clean the track and the wheels before running them, yet the same problem could still occur even right after cleaning.

I've also just swapped the 30° crossing in the middle of the double reverse loop with an identical nickel silver piece, which seems to be only a slight improvement.

Quote from: CNE Runner on August 14, 2024, 03:51:48 PMIt has been my experience that short locomotives can be temperamental at best. Case in point is the Bachmann GE 45 tonner. I presently own 3 of these units (1 fit only for parts, 1 ran poorly out of the box...an estate purchase, and 1 that runs like a fine Swiss watch). The secret is to install a "Keep Alive" module. My #4 (the 'Swiss watch') still has the original DCC circuit board (yes, with those ridiculous orange headlights); BUT I [had] added one of the many mini Keep Alive/Current Keeper modules. Before I had to clean the track almost daily and I still had problems. Enter the Keep Alive/Current Keeper and all those problems disappeared. I don't presently own a Bachmann GE 44 Tonner; but that could be a relatively inexpensive fix for the problem. Just saying...
That's really cool, I'll definitely keep this in mind.