What is the maximum recommended distance between feeders along a length of track?

[Mark Walther]

I have not seen the answer to this question.  I presume a need to provide feeders to rail between or beyond turnouts and any track I may wish to isolate, but how many feeders for a given length of single track?  Every 3 feet?  Every 10 feet?  Every 25 feet?  The DCC books I have read speak of the need for feeders off a buss due to voltage drop, speak of wire gauges, but not the distance between them. I do not want over or under build. Keep in mind that I am building a two level (lower is staging) 8' x 13' donut layout.  I would be happy to get by with one pair of feeders. I need to buy wire and connectors and need to know how much/many I need.    

In this same vain, how many DCC districts would be wise for this pair of 8' x 13' levels. I expect to set 2 trains running around the walls and operate 1-2 other engines/trains elsewhere at the same time. I will likely be the lone operator, but might have someone join me.

I appreciate your advice in advance. 

[MisterBeasley]

To paraphrase Jason Robards Jr. in A Thousand Clowns, you can never have too many feeders.  I like to use them at least every six feet, with extra feeders  when that distance is interrupted by turnouts.

Yeah, it's a lot of feeders, but the reasons are worth it.  Rail joiners aren't reliable connectors.  Nickel-Silver rail isn't as good a conductor as copper bus wire.  Most important, once you finish and ballast the track, fixing power problems becomes much more effort.

I think wiring your proposed layout structure for DCC would work with two power districts, one for each level.  If there's a heavy concentration of track somewhere, like a yard, it might be convenient to make that a power district of its own.  Also remember that a reversing section powered by an auto-reverser is automatically a power district and should be wired as such.

[RRRR - Rat Room Rail Road]

I am fairly new to the hobby, but my research confirms the above - about every 6 feet max.  Running feeders is pretty easy, so I actually did it more frequently in some sections where there were turnouts or on my helix.

[betamax]

Have a look at the chart on this webpage Wire Size and Spacing. As others have said, you can never have too many feeders.

[Overmod]

Mark Walther

I would be happy to get by with one pair of feeders. I need to buy wire and connectors and need to know how much/many I need.

Here we go again.  We have just had a fairly detailed thread about just how few feeders might be objectively needed for, say, four potential trains' worth of operation, while of course there's much to be said (I say it too) that you want as many feeders -- and carefully-marked wiring and connections -- as you have sections of rail.  

As noted, you can have perfectly good 'conductivity' with nothing more than rail-joiner feeders every other joint in the track, and while the joints are generally better soldered, not all of them need be.  

One of the points of DCC is that you don't need formal 'districts' separating operating trains.  The 14V on the rails is continuous and doesn't need to be reversed for direction as DC does.  I recommend that you find some way to show your intended track plan and details here, as there are world-class people who will give you, free, advice worth a great deal of money in more than a few respects.

[PennCentral99]

Every other joint and each rail on turnouts. This way, you have electricity coming from each direction, with less chance of a dead spot. Notice I said "less chance", I didn't say it "completely eliminates" a dead spot.

Terry

[MisterBeasley]

Overmod

One of the points of DCC is that you don't need formal 'districts' separating operating trains.  The 14V on the rails is continuous and doesn't need to be reversed for direction as DC does.  I recommend that you find some way to show your intended track plan and details here, as there are world-class people who will give you, free, advice worth a great deal of money in more than a few respects.

There is a point we've been discussing lately about the value of dividing a DCC layout into distinct power districts to limit the power in any individual district.  With boosters now putting out 8 to 10 amps, we should be careful to limit the power to any section of track to a fraction of that, perhaps 3 amps.  Circuit breakers can do this easily.  Yes, a booster can drive a single district easily, but you really don't want all that extra power to dump through your tracks in the event of a short.

[Pruitt]

This question fits in the same category as "How thick should my subroadbed be?" The correct answer depends on your construction methods and standards. Eight to twelve feet is fine, if the rail ends are properly prepared and rail joiners properly installed, whether you're going to use short-cut methods to attach feeders to buss lines, etc. 

From what I've observed over the years, as often as not rail joiners are improperly installed on poorly prepared rail ends, and the forest of feeders are poorly connected to the buss lines using "suitcase" connectors (which themselves are not well installed). Under those circumstances, you need feeders on every single piece of rail.

(Waiting for the outrage...)

[Mark Walther]

I am trying to post my layout plans and I am struggling with format etc.  Here goes first try:

Lower Level Staging:  

Upper Level Main:  

[Mark Walther]

Well, that did not work.

[gregc]

nickle silver rail is the equivalent of 26g wire

if you solder every other rail joiner and solder a feeder to it, no track would be further than 3' from a feeder.   feeder will be ~6' apart

rail shorter that 3' can be soldered avoiding the need for extra feeders

of course block or frog gaps will require feeders closer than 6' 

 

[JoeinPA]

No outrage. Thanks for the sanity Pruitt.

Joe