Why does the top of my track become black?

"Dirt" is in the air we breathe. It's the blown-around "shavings" of every blasted thing on the planet, as they deteriorate or grow. That's why we have mucus membranes.

Dirt is all the tiny and even microscopic stuff floating around right now. Oil is sticky, relatively. Also, around moving machinery (i.e. model RR equipment) there is constant wear and tear.

Oil also undergoes chemical changes when exposed to air. It can darken.

Dust, grease, smoke fluid and oil from the atmosphere and your equipment

Don't forget deposits from the traction tires, which are black.  It is also the result from electrical "arching" between the outer rails and wheels of engines and lighted cars.

Traction tires,Plastic wheels,dirt and electrical arcing. The units I run with metal wheels very seldom darken or dirty my S gauge track. I think the biggest culprit is oil and traction tires.

Gunny

@RON ARNDT 091718 posted:

Don't forget deposits from the traction tires, which are black.  It is also the result from electrical "arching" between the outer rails and wheels of engines and lighted cars.

This morning I made my bi-mothly maintenance run to our tax/accounting guru's office.  He has a ceiling-mounted G gauge layout throughout his waiting and main office rooms.  Two trains automatically trade start/stops at the 'station' area in his office.  The passenger train consists of four 2-axle LGB coaches and the Stainz 0-4-0 locomotive.  Runs well....until the brass track, the minimal electrical pickups on the engine (3 of four drivers and 2 sliding shoes) become dirty, and then it's a rather herky-jerky traverse, sometimes coming to an immediate halt.  The larger freight train is an LGB 2-8-2 Mikado...LOTS more electrical pick-up points, weight, etc...nary any running hesitation ever.

It's the never-ending problem with D-I-R-T....on the rails, on the wheels, on the sliding shoes.  The crud on the 0-4-0's drivers (1 non-black traction tire, 3 metal-tires) and shoes was cleaned up with two cotton swabs dipped in Goo-Gone.  We're talking BLACK crud.  I also ran a Rube Goldberg track cleaner car having a wood block with a pad of Goo-Gone spritzed paper towels fastened to the sliding suface.  Two trips around the layout (brass track) and that was black, also...but not too bad for the amount of track IMHO.  A final trip with a dry pad completes that process.

The right-of-way was also vacuumed and given a noisy buffing treatment by the LGB motorized track cleaning machine.  The brass rails are good for another 2 months.

All car wheels are metal-rimmed...no plastic.  Every time I check the car wheels, they're bright, shiny, no gunk showing.

Some time ago I happened to mention this maintenance routine to an electrical engineer.  Sez he, in effect: "All sliding or rolling metal electrical contact points have some degree of arcing, often not even visible to the naked eye in a darkened room.  That sort of arcing can generate micro-particles of carbonaceous (read: black) material, which over time may reduce conductivity resulting in poorer performance, especially for low power applications."

I know there's a lot of blame-game about the role of plastic wheels, black rubber traction tires, fluids intended to clean track, fluids intended to improve contact performance, etc., etc., etc., blah, blah, blah.  But I've since heard/read similar comments as made by that EE, and have come to believe that imperceptible contact arcing is probably a major contributor to my CPA's layout maintenance frequency...and my own O3R layout. 

Ah, well, 2-rail or 3-rail, AC or DC power, BIG trains or little trains, indoors or outdoors, smoke or no smoke,...maintenance is inescapable.  It's part of having fun.

IMHO, of course...

KD

No traction tires or oil on my center rails, but they still turn black. Also, since I built a new layout with O60 and O72 curves six years ago, I haven't changed one traction tire. I'm in with the electrical deposits explanation on this one.

This is the best explanation I have heard for the black gunk.  Basically what KD said with more details.  Also tells you how to minimize it with low dielectric constant cleaners.

Model Railroad Hobbyist magazine

Like other hobbyists reading this Forum, from time to time I clean my Lionel tubular track the "old-fashioned way" with 91% Isopropyl Alcohol and a cotton rag. That process removes built-up black crud - from arcing, mostly.  However, the BIG improvement in performance (on my layout, at least) is cleaning the loco wheels and pick-up rollers in addition to cleaning the tracks. BTW, I have three different "track cleaning cars" on hand, and I use them occasionally for a quickie cleaning between thorough cleanings done by hand with alky.

I lay the loco upside down in a foam cradle and use hook-up wires (red & black with alligator clips on both ends) from the variable track power outputs ("hot" and ground posts) of a Lionel 1033 transformer to a pick-up roller (red wire) and to any grounded metal site on the loco frame (black wire). Open the throttle and spin the wheels - slow to medium speed works best for me.

With cotton swabs and the alky bottle handy, I start the loco running in the cradle, then press "wet" cotton swab tips to the wheel treads and flanges until all the black stuff is removed. Then press the "dry" end of the swabs to the wheels and flanges to soak up any excess fluid.  About 12 cotton swabs later, the loco is ready to run for another 10,000 scale miles! Be careful with the fuzzy swabs - don't let cotton fibers get caught in the loco drive gears!.

If necessary, I use an Exacto knife blade to remove the last bit of black crud that often collects in the "angle" where the wheel treads meet the flanges.

I know, some manufacturers recommend GOO BE GONE (not alcohol) for cleaning.  I've tried that product, but that cleaning session sometimes required a follow-up cleaning with alky.

IMHO, some locos are "blamed" for poor performance when the culprit is actually dirty track and/or black crud on the wheels or pick-up rollers.

Mike Mottler    LCCA 12394

One of the worst ways for stainless steel or nickel-silver track to become black is from mouse urine.

Andrew

@Lehigh74 posted:

This is the best explanation I have heard for the black gunk.  Basically what KD said with more details.  Also tells you how to minimize it with low dielectric constant cleaners.

Model Railroad Hobbyist magazine

Lehigh74 - I switched to DeOxit from IPA after reading a similar article on the nature of solvents. I had a can of DeOxit from cleaning old stereo equipment. Stuff works great. I was concerned about the lubricant in the protectant side, but I do not see any sliding of my traction tires after using this stuff.  I just spray on a cloth and run it down the tracks.  I will try mineral spirits, if it works it might be more cost effective than DeOxit. As it is the can lasts a long time on my modest layout.

There is a caution here - mineral spirits are flammable at relatively low concentrations in air 0.6 % by volume. If someone were to run a soaked rag around the layout and then run trains, the fire triangle is complete and you could have a toasted layout. (a combustible, oxygen/air, and ignition source) Trick is to use sparingly and make sure the room is well ventilated, so there is no chance of a concentration build up. Almost the same as using Isopropyl alcohol (IPA).  We can smell mineral spirits around 1PPM - in order to get to the flammability range, mineral spirits would have to be around 6,000 PMM in the air. By comparison IPA's minimum limit is 2.0% or 20,000 PPM.

Basically when using any flammable solvent for track cleaning, make sure the solvent has completely evaporated and the smell has dissipated before running trains.

I basically never need to clean my Gargraves track but whoa, my rolling stock wheels get extremely thick with crud buildup. Now that’s time consuming getting all that crap off the wheels. I use a razor blade followed by goo gone. Very messy.

There is never a single answer to anything in life but john, KD, and others hit the head on the nail (a joke!) , the microscopic arcing is at least 51% of the cause. Based on arcane physical details that vary by layout, it shows up on some combination of track and / or wheels.

Why very significant in the middle rail? 100% of the current originated there and from there roughly 50% flows through each side wheels and outside rails.

@ScoutingDad posted:

Lehigh74 - I switched to DeOxit from IPA after reading a similar article on the nature of solvents. I had a can of DeOxit from cleaning old stereo equipment. Stuff works great. I was concerned about the lubricant in the protectant side, but I do not see any sliding of my traction tires after using this stuff.  I just spray on a cloth and run it down the tracks.  I will try mineral spirits, if it works it might be more cost effective than DeOxit. As it is the can lasts a long time on my modest layout.

The DeOxit is on the list of the NON-POLAR cleaners that do not promote the reoccurrence of the black track. The list of non-polar solvents starts with WD-40. A friend of mine when to WD-40 to clean his N gauge track and found that instead of having to clean every few weeks to not having to clean after months. DeOxit is way up on the list.

And don't forget that about 100 tons of "space dust" falls to earth earth day!

Ron

1st, a big THANK YOU for your input.  Here's my current status:

1.  I don't like 'dirt from the air"

2.  I DO like 'traction tire deposits'....especially when slipping.

3.  I'm still 'neutral' on arcing [a flux of electrons, some of which are  converted to photons, I believe.].   I'll check with an EE model RR'r.

4.  My center rail also turns black,  but somewhat less than the outside rails;  the rollers stay clean.  [A confusing issue, to be sure!]

5.  The wheels of my rolling stock become coated with black 'stuff'.

6.  Mineral spirits leaves a film.

7.  99% isopropyl alcohol leaves the track 'squeaky-clean'.

When you use “mineral spirits” use them sparingly! And you will be far ahead of alcohol.

I have a home-made rail wiper (with a replaceable denim cloth pad) on the first car of most trains, on different layouts in different scales. So my regular trains clean the tracks. A ounce of maintenance prevents a load of other hassles. Dirty wheel problems are greatly reduced.

I have CMX track cleaning car. Is there a non-polar Liquid cleaner/protectant that is compatible with this car. Would there be a a problem with the O rings deteriorating?

@Trestleman1 posted:

I have CMX track cleaning car. Is there a non-polar Liquid cleaner/protectant that is compatible with this car. Would there be a a problem with the O rings deteriorating?

I bought some assortments of o-rings at Harbor Freight...different types of material. Viton, etc. If your o-rings get gummy, just replace them.

@phil gresho posted:

6.  Mineral spirits leaves a film.

7.  99% isopropyl alcohol leaves the track 'squeaky-clean'.

After using it for years, I switched from 91% alcohol to mineral spirits after I read the article I linked above.  I've found that the mineral spirits cleans much faster than alcohol and the track and wheels stay clean much longer.

I have noticed no film with the mineral spirts.

Did you mean to say 91% alcohol?

No.  Mine is 99%.

Bob:  Here's more:  I get via special order from my drug store.  Funny:  My experience with mineral spirits vis-a-vis isopropyl alcohol [99%] is just opposite of tours.....

When I had my home layout, I used to use denatured alcohol for cleaning track.  Of course used while the room was well-ventilated and avoided getting it on my hands and away from flames (duh) .   That stuff worked far better than standard rubbing alcohol and without leaving that residue that Goo Gone and some others tend to leave.  But that was well before I became aware of what the black gunk really was, and by the time I did I already had a few quarts of the denatured alcohol, so the plan was to use those up before switching over to non-polar based cleaning medium, but by then life changes happened and the layout was dismantled.

The black deposit on the rails is O scale coal dust and/or diesel fuel, both invisible to the eye due to their size.

Dale

@falconservice posted:

One of the worst ways for stainless steel or nickel-silver track to become black is from mouse urine.

Andrew

Andrew, I just can't stop smiling my friend. But I must ask you, what do you use to clean your track?

Bob:  I'll admit your references are pretty impressive.  I'll ponder them seriously....

FYI...I wrote CRC Products Technical Services to ask which of their 100+ products they recommended to clean model train track. Their response was CRC 05103 QD Electronic Cleaner

@Bruce Brown posted:

FYI...I wrote CRC Products Technical Services to ask which of their 100+ products they recommended to clean model train track. Their response was CRC 05103 QD Electronic Cleaner

Which shows you they know absolutely nothing about the topic!

I think the AC current used for the command control stuff creates a static electrical field around the rails.    This then attracts dust in the air sort of like a magnet and steel shavings.    I think this where the black gunk comes from as mentioned above.    It is the microscopic dust particles that are attracted to rail. 

I use DCC and the signal is carried in a square wave AC current.    I think the typical 3 rail Digital control systems also use an AC carrier.

I don't think it is plastic wheels.    The plastic wheels I use on some cars are Athearn and WEaver and the material is called "Engineering Plastic".    ONe brand you may have heard of is "Delrin".    The point is when I was still working at a Tooling compnay, Engineering Plastic was used in some applications for slide bearings on automated lines - to slide a weld gun or tool into work position.    These things are made to run 60 or more jobs an hour for 4-5 years, at least 2 shifts a day.    So in my opinion there is no way that material like that can drop particles off the wheels.

Have you read this article by Joe Fugate in Model Railroad Hobbyist?

Keeping your Track and Wheels Clean Longer, top of the index.  It actually doesn't have anything to do with AC on the rails.

As I understand it, that black stuff on our rails is similar to a problem that people have in maintenance of radio broadcast towers. Linn Westcott wrote about this in Model Railroader around 50 years ago. He introduced model railroaders to a product used by radio tower people, "No-Ox ID A Special". It is inexpensive, long lasting, and effective in reducing track cleaning. Mr. Westcott used it on brass rails, but it can also be used on tubular track. Using "No-Ox ID A Special" is a little involved and the instructions must be followed. Rather than trying to describe how to use it, I will just give you a link:
https://dfarq.homeip.net/how-t...eaning-lionel-track/

Lots of similar products, check out stuff like Deoxit-D5 and similar.

@John in California posted:

As I understand it, that black stuff on our rails is similar to a problem that people have in maintenance of radio broadcast towers. Linn Westcott wrote about this in Model Railroader around 50 years ago. He introduced model railroaders to a product used by radio tower people, "No-Ox ID A Special". It is inexpensive, long lasting, and effective in reducing track cleaning. Mr. Westcott used it on brass rails, but it can also be used on tubular track. Using "No-Ox ID A Special" is a little involved and the instructions must be followed. Rather than trying to describe how to use it, I will just give you a link:
https://dfarq.homeip.net/how-t...eaning-lionel-track/

Hello John,

Thanks for the information and link to the No-Ox ID A Special grease.

Attached is a link the explains the many uses for this electrical grease.   Seems to be a cure all for many electrically related issues.

https://www.sanchem.com/electr...ntact-lubricant.html