# HOW TOLERANT OF DIRTY TRACK IS DCC?



## Jima (Oct 28, 2018)

Thinking of getting back into the hobby after 17 years out. One of the reasons I left was the inability to keep my track clean. My layout is in a garage and must share space for storage and an RC airplane hobby as well. Was wondering that since DCC maintains full voltage on the track at all times, that it might be a little more tolerant of dirty track and wheels?

Thanks
Jim


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## D&J Railroad (Oct 4, 2013)

Dirt anywhere in the electrical path will cause problems of one degree or another. The type of track you have is a factor. Brass track is a high maintenance factor due to oxidation. The nickle silver track solved a lot of that issue and really only needs a wipe down with a mild solvent to keep it clean. Never use abrasives on the track or wheels. It leaves small scratches which will capture crude.
The same with the wheels of your locomotives. The older wheels captured crude pretty fast. The newer wheels of nickle silver are easy to clean, and once again, should never be cleaned with wire or abrasive.
Keep those too points in mind and DCC or even DC at that will be just fine.


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## mesenteria (Oct 29, 2015)

Jima said:


> ... that it might be a little more tolerant of dirty track and wheels?
> 
> Thanks
> Jim


Jim, regrettably, DCC is very unforgiving of breaks in continuity of any kind...UNLESS...the package includes keep-alive devices on the motherboard. These days, more and more suppliers of decoders have accepted that there's a really nasty complaint in the hobby about how finicky the decoders are about intermittent power pickup, so they have begun to include capacitors, substantial ones, on their installations. This has changed things for the better. In fact, you'd be surprised how many modelers have opened up their locomotives to add their own.

Keeping track clean is easy. If you had electrical pickup problems, it may have been dirty track, but it could just as easily have been three or four other problems, maybe by themselves, maybe in addition to some dust buildup on the rails. Wipers wear, oxidize, get gung buildup that forces them away from the wheel backs, solders give, wires get chafed inside and hear spinning components, connections at the decoder wiggle loose...the list goes on.

All properly laid and electrically supplied track needs is an occasional wipe with a dampened clean drop cloth remnant 9I always have a bag of the strips of bedsheet material that I buy locally at a paint shop). If you don't rely on joiners to connect the tracks more than mechanically, and NOT electrically, if you have a pair of feeders connected to most rail elements, and you run trains occasionally with metal tires AND wipe the rails once a week (a five minute job at most), and still have problems, you must have problems other than 'dirty tracks'.

If you are convinced that I am mistaken based on your recollections and experience, I would recommend that you build the layout, and then wipe the rails with automatic transmission fluid. Make sure it's the Dextron III Mercon variety that is safe for paints and plastics. I did this for giggles just prior to dismantling my second layout, and I had grades in the 3.5% range, a bit steeper actually. I let several locomotives with heavy trailing trains (especially for those steep grades) run in both directions and noticed no degradation in performance. What I assumed, though, is that the coating prevented oxidation..IF oxidation is a problem with nickel-silver, and the science says it isn't that big of a deal for model trains. The lube did not affect mechanical performance, and I never did have electrical problems, so I can't say the lube improved pickup somehow...I doubt that it did, but it certainly did not hurt. Others report that Wahl's Clipper Oil works wonders.


If you have a particularly tricky spot that a meter always shows is getting full DCC voltage, try a light swipe of Neo-Lube or whatever that lube is that is also partly electrically conductive. It might just help.


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## DonR (Oct 18, 2012)

Doesn't matter whether you run DC or DCC, the key
to smooth loco operations is good electrical conductivity.
Thus the track, joiners included, must be clean and free of non conductive corrosion. 

For the most part a DCC decoder will ignore some slight
loss of track power. They don't quit or need resetting
as you might assume. The lights may blink but the loco
usually continues on. Even so, for smoothest operation
cleanliness is very important. 

A garage layout will mean the need for more
maintenance. Before you run your trains for the
first time in a while carefully clean the rail tops.
Then run a track cleaning car around the layout before
every operating session.

Also make sure that your loco wheels are clean before
every session. I use a paper towel with an alcohol spot
placed on the track. Run the front wheels onto the alcohol and
turn up the loco speed as you hold the loco, spinning
the wheels and cleaning them. Do the same with
the rear wheels. But you'll also want to
clean the car wheels so they don't track dirt onto the
rails. That is not as easy if they are caked with gunk.

That being said, go ahead and convert to DCC. With
good maintenance, you should have no problem It is
so superior to DC that you'll wonder why you didn't 
go with it before.

Don


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## Lemonhawk (Sep 24, 2013)

The key to using ATF is to use very little. Dab it on in a few places and the trains will carry it around. Does seem to really reduce how often you need to actually clean the track.


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## CTValleyRR (Jul 26, 2014)

D&J Railroad said:


> Never use abrasives on the track or wheels. It leaves small scratches which will capture crude.
> 
> ...and once again, should never be cleaned with wire or abrasive.


I would say that if anything, DCC is slightly less forgiving than DC, but the other guys have summed it up pretty well. If you've been away for 17 years, the changes in track and wheel composition make it extremely easy to keep things clean, and ensuring good electrical continuity is far more important.

That said, I think the advice I quoted above is like the fish that got away: it keeps growing with the retelling. You CAN use mild abrasives like metal polish or specially designed track cleaning blocks, and even sandpaper of 800 grit or higher, as well as brass-bristled wire brushes to clean stubborn spots of grime, like when you have accidentally gotten glue or paint on your rails, but these shouldn't be used for everyday cleaning. Somehow "use with caution and sparingly" has become "don't ever use".

In any case, nickel silver rails that do become nicked or scratched can be restored by burnishing them with a large steel washer.

The only absolute no-no is steel wool. It sheds fibers, which can be attracted to the magnets in your locomotives' motors and ruin them.


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## J.Albert1949 (Feb 3, 2018)

Lately, I've found that dirty wheels on the engines are more of a problem than is "dirty track".

I use Don R's method above for cleaning loco wheels (paper towel on track with a little alcohol, clean one truck at a time).

The last time I ran trains with dc was in the late 1970's. Then I took a 40-year break from the model trains, started up again with them this year.

But I noticed right away that dcc seems to be more finicky about dirty track/engine wheels than with dc.

Seems like my engines need a cleaning every day (or at least every other day). Failing to do that, they'll run, but they seem a bit more "skittish" in a few spots with even a little grime on the wheels.

I'll _guess_ that even a momentary (milliseconds?) interruption in the dcc signal is enough to produce a noticeable "twitch" in the engine's performance.

Perhaps it's time for the manufacturers to include at least a very basic level of "keep alive" in ALL their boards. The amount of the keep-alive doesn't have to be particularly long, perhaps only a few tenths of a second. That will "get the engine across" most dcc "interruptions" without problems.


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## Jima (Oct 28, 2018)

Thanks for the advice guys. My equipment is also 17 or more years old. A couple of my blue box Athearns are approaching 30 years old. All of the wheelset axle gears have split on them. Just ordered some new ones with nickel silver wheels. Hope they work better. Also have 4 IHC Premier steam engines. These all have Nickel Silver wheels. When I pulled them out of the box there was no corrosion on the wheels just the crud left on them from the last time they were run. However, the pickups on these wheels are all copper. Had to clean them. And then cleaned the wheels and these engines ran as smooth as the day I bought them. These are some really good runners. 

Anyhow, the reason I asked this question was that I thought since the rail contained full voltage at all times that the engines would have a better chance of picking up juice as compared to DC where the voltage varies and it is problematic at low voltage with dusty wheels and track. Guess this is not a good reason to go DCC. However, I really like the steam sound decoders they have out these days. Maybe worth it just for the sound.

Jim


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## gregc (Apr 25, 2015)

with DC, momentum can carry the locomotive across a short loss of power before voltage is restored across the motor which may be unnoticeable.

but since DCC decoders use microcontrollers, a brief loss of power can cause the decoder to restart and it must then wait for a speed command from command station before restoring voltage across the motor.

keep alives use capacitors to provide power during a brief loss of conductivity which may prevent the decoder from needing to restart and loosing state.


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## Chops (Dec 6, 2018)

Had posted a question in this section, and this seems to confirm what I suspected about conductivity. 

What is involved in adding a capacitor, or for would it be better just to start over with a decoder with a built in capacitor, and who makes them? 

I would be apply this exclusively to some OO stuff, most of it plug and play, the rest I'd likely leave as analog.


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