How many feeders?

[Marty Cozad]

QUOTE: Originally posted by pennsyj1fan

OK, you run a lot of feeder wires for HO, how about approximately 350' of G Guage Aristo Brass track outside, anyone do G also. I usually ran one wire but haven't gotten power to everywhere I need it. I use 12 guage braided copper wire. Any tips or help I can get for this problem. Is there something I can run the feeder wire to and then hook up my new powerpack to so I get power to all the feeder wires.
Thank you.

I ran track power for about 8 years on my outdoor model railroad untill I hit the 500 ft mark and realized it was easier and cheaper to run RC on board battery power. Saves a ton of time .
In the old days I ran two main feeders and installed jumper wires on all joiners with brass to each block on the line.
Now the freedom of multi MUing and train control is great. Aristo Craft has out of the box battery ready engines to just plug into a battery car ( to start out with) and I can run any time. the only,, question I ever face is, how long with the battery last.
i have not cleaned rail, wheels, etc in 5 years. There is no wire at all on my 1,600 ft of track. BTY we also run live steam at the same time.



This lash-up of 3 powered SD 45s are pulling 35 cars and will run about two hours. I make a station stop and switch out my 18 volt DC tool batt and I'm on my way.
Takes 30 mins to recharge, thus two batt will run all day.
Theres 60 pounds of prime movers pulling appr 140 pounds of train.
I don't know if i helped but may have caused some thoughts.[;)][:p]

[selector]

If I understand your question, you must have a main bus under the length of your track, and that should be in the 10-12 guage range for your outdoor railway. Every 6-10 feet, you should have a 16-18 guage feeder wire of about 1-2' drop from the rails down to the bus, below. We're not talking 15 amp service here, right, so those guages should provide minimal voltage drop. Once your bus runs about 100 feet, though, there will be significant reduction in that initial voltage. So, at some point, the most distant from your controller, you should provide a booster in power, another power supply. (This depends on your track layout, whether a long out-and-back, or a loop.) This booster will keep the far side of your setup properly energized, and if your feeders are well installed, you should have no problems with power.

Now, I have no garden scale experience, but I'm sure the reasoning and ball-parking are fairly close. You need gapped sections, each fed, and several of them powered by their own power supply that is slaved to your controller. At least, that is the way it works in HO for the reduced voltages, wire guages used, etc. I hope someone speaks up and reinforces what I am saying. I can't think of another reason for your power gaps other than bad contacts to the tracks.

[pennsyj1fan]

OK, you run a lot of feeder wires for HO, how about approximately 350' of G Guage Aristo Brass track outside, anyone do G also. I usually ran one wire but haven't gotten power to everywhere I need it. I use 12 guage braided copper wire. Any tips or help I can get for this problem. Is there something I can run the feeder wire to and then hook up my new powerpack to so I get power to all the feeder wires.
Thank you.

[Don Gibson]

MYTH'S - or MISSES?

Expansion: Wood and Homasote expand's with moisture. Metal Rail expand's with temperature. Running increases temperature.

Ever run in the dark ?. See those electrical spark's from arc-ing?
Read David Harrison's latest post re: CMS&I's (temp. controlled) rail expansion problem's.

Nickel Silver rail: doesn't oxidize; or - it's oxide conduct's electricity.

There is no silver in nickel silver. It's an alloy of Brass.

Contaminant's cause restriction of electrical flow:

Oxidation, tarnish, corrosion, Yes. How about foreign substances (including smoke and oil). Cook bacon in the kitchen? Oil in the track cleaner? - read label.

Electrical losses per ft. of various metal's - compared to copper .

Anyone remember your LIONEL train's slowing down when it got the furthest away from the transformer?
1.Lionel track was 'tin' plated
2. brass conduct's better than nickel silver
3. differences are small on small railroad's such as 4 X 8's.
Someone else can give the loss comparison's, but it only become's significant on longer run's.

Since I have had to replace whole section's of 'bowed-out' rail (in a temperature and humidity controlled basement) I'm not being one of those 'theoretical' types, or "it never happened to me" crowd. I don't plan on having my house burn down, either, but I have fire insurance.

It seem's that for everybody there is 'Good Practice', - or practice that is ''Good enough''. Think about it.

Best part is everybody get's to choose for themselves.

[wccobb]

My personal preference is to solder a feeder to every other joiner and let the solder flow to a good bond on each rail in the joiner. 1) One end of EVERY "hunk" of rail is firmly soldered to a feeder. 2) The other end of EVERY "hunk" of rail is an expansion joint. You need both, and one expansion joint per layout might just ask for a whole lot from one expansion joint. Absolutely no quarrel with those who solder to each "hunk" of rail & leave all ends for expansion joints. Unless you've got totally controlled temperature & humidity, having lottsa expnsion joints with smaller gaps is usually better.
Yes, I'm still with DC. Can run 6 Athearn (@3.5 amp) some 40 ft. from the powerpack with no observable voltage drop. (16 ga. buss & 20 ga feeders - and agreed, that's a little light for DCC. It's wire I had and I'm being "thrifty").

[selector]

I'm confused. I'm no engineer, but if humidity causes expansion, then there should be NO buckling in the rails. Since the layout will swell radially, in all directions, including up and down, one should only observe that the gaps between the rails are widening. Conversely, when the humidity drops much below that at which the tracks were laid (gapped), then, and only then, should they close the gaps to the extent to which they might impact at the ends and deflect along the axis.

I believe that 20 feet of monolithic rail in HO might lenghten a whole 2-3 mm in a rise of 15 deg, hardly a cause for concern....for gapped rails. However, wood on which track was laid and gapped when it was 40% humidity will swell by nearly a cm, longitudinally, when it rises to 80% water content. There-in lies the problem...a five-fold (or thereabouts) increase in gap due to water content in absorbent material over the expansion of metal rails due to temperature.

Again, I'm no engineer, so my figures might not withstand close scrutiny, but I believe my reasoning to be basically sound.

As for soldering joiners, I have done none of it, and can attest to having no problems running three sound-equipped locos on my 40 feet of track , fed by only three sets of feeders, each soldered directly to the rail web.

Copper piping soldered at the joints will leach lead into the water over time, and the solders themselves will begin to exhibit copper sulfate residue when the water has any amount of dissolved sulfer in it...as we do with our well.

Nothing lasts forever.

[grayfox1119]

Mark, you make good sense. I looked up the coefficient of linear expansion with heat/cold for nickel-silver a while ago, and it is so small, that I can't believe that this causes a problem. I do believe, and have had experiences with plywood, that proves this WILL definetly expand and shrink at a far greater rate than any track will. For those that use pine for their sub track, that wood is no different, it too expands and contracts greater than the rails ever will. Our tracks are not like real rails out in the hot sun or freezing cold, we are not THAT prototypical.
So what I do, is paint all surfaces of the wood, top, bottom, and sides with a sealer. This prevents high summer humidity from swelling the wood, nor extra dryness of the winter when the temps are -10F outside and the humidity in the train room m ay be only 20%, from shrinking the wood. THIS is where all the trouble comes from, the wood, not the rails. If someone needs more proof, take some flex track, solder a loop together, and place it on a piece of poly on the cement floor. This will not kink over an entire year of temperature extremes. Now place the same loop on a piece of plywood, unsealed ( bare plywood). Check that out in the middle of summer after days of high humidity. Than again on a cold winter day, or after days of very low humidity.

[Pruitt]

QUOTE: Originally posted by mark_in_utah

High humidity with salt (coastal areas) are famous for this problem. Ever seen a swing set in those areas?
Mark in Utah

When I worked at Cape Canaveral in Florida (on the space program - manned and unmanned), one of the guys had a pickup truck that the salt air corroded so badly you could see though it! It looked like rusty swiss cheese. We all used to joke that he would be killed when he fell through the floor on the highway, and his own truck ran him down.

My first year in NJ I had some expansion/contraction problems, and my rails kinked really badly in several places. Humidity in the summer was so bad that we had trails of water drops on the floor from where the water pipes were sweating! In the winter the humidity was only about 30%, so there was a lot of variation, season-to-season. I solved the problem with humidifiers in winter and a good dehumidifier in summer. Now the basement runs 45-60% RH all year around, and there are no more kinked rails. It's not the level of humidity that's a problem; it's the variation.

[Anonymous]

Brunton,

From what I've seen and talked to other people about this, the layout expansion problems "appear" to be heat related because that's when the humidity goes up iin an area. When moisture gets into wood it swells, hence the layout gets bigger and the rails buckle. By adding expansion joints you're accomodating this process in your design. You can also control the humidity or move to a drier climate to solve the problem as well. Design or material changes can eliminate the problem up front. Foam doesn't swell with humidity. Those people that build their layouts on foam probably will never see a problem.

The corrosion that we're all worried about is a slow acting effect, and it's mostly galvanic corrosion. Whenever two dissimilar metals come in contact, a battery action is formed. If water is allowed into that point then you can get an "electroplating" effect, where metal is transported from one side to the other. Obviously not good.

The other corrosion is a chemical acidic action which is caused by the residual flux and again, moisture. In this case, a stranded wire is WORSE simply because you have a much higher surface area per unit volume of copper. If you're truly worried about corroding wires you should go to solid wire whenever possible. Stranding makes sense though in those cases when you have to repeatedly move the wire. Solid wire is less durable in that situation.

Obviously corrosive fumes are bad news. High humidity with salt (coastal areas) are famous for this problem. Ever seen a swing set in those areas?

In this whole discussion I think the main thing to remember is that you have to build according to the environment you have to deal with. The addition of tons of feeders may be overkill, but once you've been bitten by a problem, you tend to keep hitting it with a hammer until it's been dead for a very long time.

Mark in Utah

[BRAKIE]

First let me explain I never been one for feeder wire overkill.Now in that truth I drop feeder wires every 6-8 feet which I find works quite well.Now on small industrial switching layouts 10 feet or less in length I do not use feeders.
Now on the few loop layouts I have built over the years I usually use Atlas sectors for block wiring and fore go any feeders as they are not needed.You see I simply run a single wire from the track to the selector per Atlas' instructions.Simple yet efficient.

[Pruitt]

Interesting, mark_in_utah.

I wonder just how many of the "Dos and Don'ts" in model railroading that are taken for granted are urban myths?

I wonder - is there any real difference between the rails expanding and contracting, and the foundation on which the rails are laid expanding and contracting? Since the net effect is the same - kinked rail or joint gaps, it kind of amounts to the same thing, I think.

If a solder wire joint corrodes in an environment where someone is breathing, they'd better check what kind of solder they're using (rosin or acid core), and if it's rosin core, they should get out fast! They're probably corroding their lungs, too!

Over time you might see some corrosion if you store caustic materials in the train room (like lead-acid batteries, for example), but I can't imagine that you would otherwise. And other things on the layout will show the corrosion MUCH earlier than the solder on the rail! I suppose over LONG exposure someone living in Florida or someplace else where salt air is common might see some galvanic reaction at the soldered joint, but it would still be apparent in loco meachnisms long before it was obvious at the rail joints.

I agree that soldering a rail joint will improve the electrical connection over just a friction-fit mechanical connection, but so far I haven't experienced enough degradation in a connection to do all that soldering.

Mark_in_New_Jersey (go ahead and laugh - it makes ME want to cry!), also a PE [:o)]

[Anonymous]

QUOTE: Originally posted by Blind Bruce

Mark,
Even stranded wire will "wick" solder and cause the feeder to be stiff enough to flex the rail. This alone would stop me from using material on hand as it were. How do you, or propose to do, the installation of the track through the roadbed and sub-roadbed, without bending the rail?
BB

Its easy. Simply drill a hole through the whole mess directly under where the feeder is installed. Stuff the feeder down through roadbed. subroadbed, etc. Out of sight, out of mind. The feeder is trained so that it helps hold the rail in place. No strain is placed on the feeder to cause the rail to twist or flex.

As for the need to keep plenty of slack in the joiners for track expansion and contraction, I firmly believe this is an urban myth. Of more concern is the expansion and contraction of the layout under the track due to the changes in relative humidity. The coefficient of expansion of the track is so low that it should never be an issue. If you're having problems with yout layout shifting around with the weather, then you need to make allowances or fix it. I don't anticipate any due to my construction design and location.

Those that are worried about solder causing corrosion should be very worried about their plumbing, if they have copper plumbing in their home. It's a non issue. Leaving flux all over the thin wires on the layout could be an issue though. Wash it off. Even rosin flux is a problem. Clean it off too.

Soldered connections are not a friction fit connection. Solder reacts with the metal surface that it's bonded to creating an amalgam. This is a very strong connection. I've seen soldered connections that coul literally be used to pull trucks (Fords, Chevys don't need to be pulled). When was the last time you heard of a soldered water pipe pulling apart?

I agree that most nickel-silver joiners, when used on a nickel-silver track should provide good service. Because you're using very similar metals the risk of galvanic corrosion is low. The joiner also flexes a little when applied, helping to maintain a positive pressure connection to the rail. It's not fool proof, but it's decent.

I solder the joiner for two resons:

1. To improve the electrical connection.

2. To improve the mechanical connection and render the rail into an effective continuous rail.

I believe that the biggest problem for successful DCC operation is not voltage support, but transients and intermittent voltage on the tracks. I strongly suspect that the decoders lack any decent error correcting ability, and hence can go nutso in a heart beat. My philosophy on feeders and joiners is to address that problem.

Mark in Utah E.E., P.E.

[grayfox1119]

Good morning Mark, you certainly had an interesting career!! Yes , many layouts can get by with feeders at greater intervals, and this is a credit to excellent workmanship. Connections are tight, soldering is great, and track/equipment maintenance is done regularly.
Good exchange of ideas Mark, I enjoy it thank you,

[Pruitt]

QUOTE: Originally posted by grayfox1119

In order to understand why having feeders every section, and using a heavier gauge wire than #18, you need to have a good background in AC and DC electronics. Those with considerable experience in MRR'g, and have large layouts, or are members of MRR clubs, know only too well what happens when you try to get by with less than what is recommended. Small layouts on a 4x8 table or smaller, can get by without too much trouble, but as they expand, bad things can start to occur, and they wonder why. Wire is cheap, solder is cheap, yes it takes more time, but done correctly, it is done ONCE.
Don't get complacent over having no problems "now". Learn from the experts, they've been there...done it.

grayfox,

Since this appears to be a reply to my post, I'll answer.

I've been active in this hobby for over 30 years, total. Though not an electrical engineer, I have dabbled in electronics and electrical systems of varying complexity for even longer than that. I AM a mechanical engineer, and my job involves me in the grounding of airframe structural elements on military aircraft. In other words - I deal with mechanical fastening for electrical conductivity at least in part for my very livlihood. Hmmm...... Almost like rail joints..... Granted, that is not transmission of an electronic signal, but it is transmission of a extremely powerful burst of electromagnetic energy that in part is to PROTECT equipment responsible for transmitting and processing electronic signals. I probably qualify as an "expert" as much as most here do.

My layout is 31 X 29 feet, with about 29 feet X 20 feet operational at this point, running under DCC. I have had no problems, and the layout has been operational for some time now. Prior layouts in other locations have been mainly DC, with one several-year foray into Command Control via Onboard from Keller Engineering. None have ever had a problem with conductivity through rail joints.

If the initial connection is good mechanically, it will stay good.

QUOTE: from nobullchitbids:
Oxidized nickel-silver is a conductor but not nearly as good a conductor as unoxidized copper. This is why it makes sense to have a bus line mirroring the rail network -- voltage drop along the bus will be less than through the rail

Unoxidized NS isn't nearly as good a conductor as unoxodized copper, for that matter. And that's why I do have a power buss under the track. I use feeders every fifteen feet or so solely to minimize voltage drop through the less-conductive rails.

So I say again - I think requiring feeders every track section is an urban myth. I think one's time is better spent ensuring the loco is in good condition, electrically and mechanically, than in connecting hundreds or thousands of feeders between buss wires and track.

But that's just me - everyone should do what they think is necessary for their own layout.

Not an argument - a friendly discussion of varying points of view. [:o)]

[nobullchitbids]

Oxidized nickel-silver is a conductor but not nearly as good a conductor as unoxidized copper. This is why it makes sense to have a bus line mirroring the rail network -- voltage drop along the bus will be less than through the rail.

Handlayers have the best situation: Simply solder a feeder to the very bottom of a rail ahead of time and drill a hole through the ballast board and whatever else is in the way to the bus. If the rail be properly positioned, the hole will lie between two ties and, once ballasted, become invisible. The feeder then is soldered to the bus with a T-leg joint.

You can continue to use rail joiners if you want, but they no longer really are necessary except perhaps on curves, where the joints should be soldered to avoid ticks or kinks. If retained, they do provide an alternative path for the juice, and cutting the load on any section of wire or rail further reduces the amount of resistance, which can't hurt.

For those retaining joiners, I recommend soldering only one side of them -- the free side will allow for thermal expansion and contraction and help prevent bowing or kinking.

[grayfox1119]

In order to understand why having feeders every section, and using a heavier gauge wire than #18, you need to have a good background in AC and DC electronics. Those with considerable experience in MRR'g, and have large layouts, or are members of MRR clubs, know only too well what happens when you try to get by with less than what is recommended. Small layouts on a 4x8 table or smaller, can get by without too much trouble, but as they expand, bad things can start to occur, and they wonder why. Wire is cheap, solder is cheap, yes it takes more time, but done correctly, it is done ONCE.
Don't get complacent over having no problems "now". Learn from the experts, they've been there...done it.

[Blind Bruce]

Mark,
Even stranded wire will "wick" solder and cause the feeder to be stiff enough to flex the rail. This alone would stop me from using material on hand as it were. How do you, or propose to do, the installation of the track through the roadbed and sub-roadbed, without bending the rail?
BB

[Pruitt]

I guess I should mention - i'm using DCC.

As everyone knows, oxidized nickle-silver is a conductor. So only heavy corrosion OTHER than oxidation will cause a conduction problem at the rail joiner. If you've got THAT kind of corrosion going on, your motors and electronics will be in a lot worse shape than your track joints, much earlier!

I'm sure few will agree with me, but I think the "requirement" to solder feeders to every track section is one of the great urban myths of model railroading. In HO and smaller scales, the weight of the rolling stock is insufficient to cause properly installed rail joiners (i.e., tight, with rail ends aligned) to work loose. They can oxidize, but only very rarely will one experience a serious electrical conductivity problem.

[Don Gibson]

Soldering to Rail joiner's may improve (electrical) continuity between 2 pieces of rail ... BUT ... it creates other problem's.

the solder joint must extend beyond the joiner to the rail to be effective
the firictional coomponent allowing safe expansion is negated
distortion of the rails (bowing) can result - requiring track replacement
the resistance in each segment of rail still adds up
and soldering to the bottom's of rail joiner's raises the height off the ties - creating a bumpy joint

Since the main objective's of a feeder system is distribute voltage equally and avoid losses from 'Daisy chain-ing' pieces of rail, I suggest that today soldering rail joiner's might be considered passe'.

[Anonymous]

QUOTE: Originally posted by grayfox1119

Mark, he was referring to UNSOLDERED connections, which CAN oxidize under conditions of moisture present in the atmosphere of the train room. Some connectors may not be as tight as one would think, this allows moisture and air to join together to form an oxidation on the contact surfaces, which of course is a great insulator...no contact, or poor contact...no voltage or a high resistance causing a voltage drop that little resistor called "oxidation".

That falls back under the unsoldered joiner, where I'd suggest that you connect a feeder to each section. I agree, a loose joiner will eventually cause most people problems. There are a ew people that advocate soldering the joiners AND installing a feeder for each track section, which I feel is severe overkill. That said, it's better to be "over-killed" than still walking.....

As for using the heavier wire for the feeders, it's stranded and I happened to have it on hand. Should I be penalized for being a cheapskate?? :-P I solder it to the bottom of the track between the ties, so it's fairly hidden, and I haven't even ballasted yet.

Mark in Utah

[Blind Bruce]

Mark, Isn't 18 a little much for a feeder? Or do you have a 10A motor to support?
BB

[grayfox1119]

Mark, he was referring to UNSOLDERED connections, which CAN oxidize under conditions of moisture present in the atmosphere of the train room. Some connectors may not be as tight as one would think, this allows moisture and air to join together to form an oxidation on the contact surfaces, which of course is a great insulator...no contact, or poor contact...no voltage or a high resistance causing a voltage drop that little resistor called "oxidation".

[Anonymous]

Maybe this sounds heretical, but just HOW do you get corrosion in the middle of a soldered joiner? If done properly, the electrical connection will not fail, no matter how long you wait. Corrosion requires air and moisture to get in. A proper soldered connection is a solid metal mass. Corrosion might happen at the edges, but the rail would have to corrode in half, not likely.

If it's a cold solder joint, you're screwed. They're generally easy to spot as you do them.

If you have feeders every 10 feet, and solder all of your joiners, then you're only at most 5 feet between feeders, and in reality you're a lot closer than that when you calculate in the contribution of the rail coming from the other direction.

If your joiners are not soldered, such as at a turnout, then you should run a feeder to the track on both sides of the turnout, and not risk having the joiner work all the time.

I'm putting in 18 ga. feeders, 12 ga. buss wire, and connecting to my code 83 track. Based on my "rules", I'm putting in 35 feeders on approximately 200 feet of track and 27 turnouts.

Mark in Utah

[claycts]

Thanks people, I am using 600 ft of Code 83 with 80+ turnouts and full DCC. I was getting ready to start benchwork next week, as soon as I fini***he room that is, and these type of threads have saved me a lot of time and money.
Thank you.

[grayfox1119]

Again, the soldering the connectors, and having feeds to the rails more frequently, is FAR more important when running DCC. You can get away with much more with DC. I have a Christmas display that covers 16 feet of 4 feet X 4 feet 3/4" tables. So every year, we set up the tables and use E-Z track for the layout. NONE of the connectors are soldered ( obviously) , but we are only running DC at this time. In 10 years of harsh New England temperature and humidity extremes, we have never experienced any power problems with any of the locos run on the layout, which has one large loop of approx. 70 feet, many curves around mountains , with only one power feed. If this was running DCC, we would be in deep doo doo .

[Blind Bruce]

I can't speak for Mark C but I sure will give the bench soldering a try. The feeders in the center make sense to me also. It should be much easier to solder one, solid, lead on a rail than try to flow solder into a crimped joiner. I give it a "yea"
BB

[claycts]

Mark C, soldering in the middle of flex track makes sense. I was thinking (at my age that is good) that I would put a pair of 18" pigtails on every piece of flex track at the bench before it gets to the table. That way i could use a resistance system and only have the little pieces to do at construction.
Yea or nay?

[jimrice4449]

My "bullet proof" method is to solder a feeder to every other rail joiner and then solder the rail joiner to the rails on both sides. This, effectively gives you 6 ft. rail sections w/ a feeder to every section.

[Pruitt]

I have feeders every 15 feet or so. Rail joints are soldered only on curves.

In many years of model railroading (around 35 now - geez, I'm old!) in many different parts of the country (Seattle, California, Wyoming, Florida, New Jersey), I have
N E V E R
had a problem with rail joiners loosening up and not conducting electricity properly.

Heresy!! But I have better things to do than solder feeder wires until I'm blue in the face. So I guess the Gods of righteous Model Railroading will be coming after me in my sleep now!

Then again, I DO prep my rail joints by cleaning the underside and sides of the rails at each joint with a cutoff disk at low speed in my Dremel. Provides fresh bare metal for the joiner to grip.