I have a completely unscientific theory that the crud begins as a nearly invisible film on the rails that gets picked up by the wheels of passing trains. Over time, it accumulates until it becomes a problem with tracking. That said, I just randomly checked a number of pieces of rolling stock and many of them have at least some crud on them. I then walked the entire layout and found no accumulations of black gunk.
Rich
Alton Junction
Now how would you explain a set of MTH hoppers run as a group that I put on the rails straight from the factory. Started getting derailments at one point on a run around track. Picked up offending car and it had black gunk and only on one side of the car and only this car, cleaned it up and all is fine but why one car and one side out of 6 cars?
LastspikemikeWell, thanks for clarifying all that. The physicists among us will be relieved it's not all that complicated after all.
They are probably afraid to say anything.
Ed
7j43kThey are probably afraid to say anything.
Wow! I never expected this thread to generate so much interest in folks. The discussion about gunk, physics, and engineering is enjoyable!
More food for thought:
1. Are certain types of locos or manufacturers more susceptible to "gunk" or dirty cars?
2. How often is necessary to avoid running locos that you don't need to clean the track (e.g., daily, 2x/week)?
1) for locos, the old Athearn blue box diesels would collect a lot of gunk because of the non-polished wheels they had. Keep in mind that loco performance is also affected by things like the number of wheels that pick up power.
2) it will depend on the level of humidity and dust in the room.
Simon
snjroy 2) it will depend on the level of humidity and dust in the room. Simon
Humidity? It DOES seem like it would make a difference, but that's only intuitive. I assume you think a HIGHER humidity is worse, but I could be wrong.
I think it is beneficial to keep one's layout in conditioned space, both for the layout and the builder. If that's done, the outdoor humidity shouldn't be affecting the layout. Where I live, the outdoor humidity is rarely a problem, anyway. We don't have AC or humidity control, although there's usually 3 days a summer where we think about it. A lot.
On dust, I absolutely believe that less dust is better. An easy one there, eh?
In Model Railroad Hobbyist they published an article on track cleaning. The black crud is caused by arcing of the wheels as they go around the track. As the powered wheels roll on the track there may be tiny electrical arcs where the wheels make and break contact with the rail.
The tiny amounts of burned material from the arcing is picked up by plastic wheels moreso than metal wheels.
The suggestion is to clean your track with mineral spirits, highly non-polar and then give it a coat of graphite (VERY lightly rubbing a H or 2H stick of graphite over the rails.)
If you are getting enough crud on the wheels to derail a car you have really bad dust problems or horrible arcing problems on your layout. That's not normal.
Model Railroad Hobbyist magazine
Dave H. Painted side goes up. My website : wnbranch.com
MRH certainly has opinions.
By this reasoning, it would appear that people who run "dead rail" have clean track. Of course, they don't CARE if they have clean track, that being a major point of dead rail.
However. It would be interesting to conduct such an experiment.
Mineral spirits can leave a residue of slow-evaporating hydrocarbons, which can then coat all surfaces. This may be good or bad. I use alcohol, which fully evaporates very quickly.
According to the chemists that MRH talked to, alcohol has about 10 times more "polarity" than mineral spirits so is more likely to cause micro-arcing, leading to more crud on the rails.
People have been suggesting using Wahl Clipper oil for decades and that article explains why it works (same di-electric value as Mineral Spirits, but not as dangerous as gasoline or diesel).
Actually a lot of "dead rail" people do have or want to have current in the track, in order to drive charging circuits and signal or detection systems. There has been a suggestion to call "dead rail", "power on board" instead, since power on board is more inclusive.
dehusman According to the chemists that MRH talked to, alcohol has about 10 times more "polarity" than mineral spirits so is more likely to cause micro-arcing, leading to more crud on the rails.
Alcohol will evaporate long before most or all of your train running. So it's kind of hard to envision how something that has evaporated is "more likely to cause micro-arcing". Polarity or not.
Could you post a link to these statements by MRH? I'd like to read every word.
Hmm. That's the same thing as DCC people using "keep alive", except more power is stored. They could certainly use much smaller batteries if they can continually recharge. Or maybe even a capacitor, like the DCC folks. It looks like then the big difference between DCC and dead rail is that the former uses a line carrier signal, while the latter uses direct radio.
7j43k snjroy 2) it will depend on the level of humidity and dust in the room. Simon Humidity? It DOES seem like it would make a difference, but that's only intuitive. I assume you think a HIGHER humidity is worse, but I could be wrong. I think it is beneficial to keep one's layout in conditioned space, both for the layout and the builder. If that's done, the outdoor humidity shouldn't be affecting the layout. Where I live, the outdoor humidity is rarely a problem, anyway. We don't have AC or humidity control, although there's usually 3 days a summer where we think about it. A lot. On dust, I absolutely believe that less dust is better. An easy one there, eh? Ed
Not intuition, experience. Our club installed a dehumidifier at some point and the track had a lot less oxidation issues. It was so damp before that our fascia would warp during the summer months! The track would have a greenish film after only two weeks of sitting iddle. The dehumidifier made a huge difference.
Cheers.
That greenish film is the copper reacting. I expect the dampness helps it to ionize to do so.
I thought perhaps extreme dryness might be a problem because of MAYBE PERHAPS greater arcing between wheel and rail.
Besides, I HATE humidity, except in the shower. I grew up in DC and moved to California. We don't even have bugs in the air, here. Maybe they're too mellow, or something. I do miss fireflies.
Yes, here in Eastern Canada, humidity is a godsend... for gardeners.
The process of burnishI got emparts a hardenled skin that resists the arcing heat and thereby reducling the pitting and accumulation of nickel oxide.
Glad to see this thread generating more discussion!
Yes it is controversial indeed
It is I that began the Burnish method back in 2006. I am still studying the longevity of it, and at 16 years now I have garnered data positive and negative. Mostly positive.
It does require work to apply but only once; Dry wipe clean with cotton T-shirt rags; No abrasive or liquid cleaner or track clean cars.
I have a small N scale layout and with the small size and DCC I struggled with constant dead spots and constant isopropyl cleaning. Never using IPA again on the rails. This RTNTs video was very informative, explained the black gunk source, and I followed what was laid out and it works great! Have not cleaned in a while. One spot was dead and rubbed it with a clean tee shirt square and reapplied very thin layer of the paste and back to it.
https://www.youtube.com/watch?v=lBYxjcTWCB0
Rail cleaning is like barbequing. Everyone has their own way of doing it and insist that their way is the best.