Newbie Here, Got a Few Questions

Discussion of N gauge model railway specific products and related model railway topics (problems and solutions). (Graham Farish, Dapol, Peco)
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RowanMackenzie
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Newbie Here, Got a Few Questions

Post by RowanMackenzie »

1) I saw somewhere that wiring for DCC layouts needs feeders for EVERY piece of track, which seems excessive. Is this true? I'm currently running a decent oval with a few sidings with only one feeder, and the loco seems to retain power just fine except for on points (because of insulfrogs I suspect).

2) I'd like to do a little verticality for my layout, and plan to use foam to build up the terrain. How would I make holes for my feeders? Would I need to make a hollow frame to put the foam on first?

3) Is there a way to get around the problems with insulfrog points? I saw somebody putting tin foil over theirs, but that was OO gauge, and I don't want to wire up electrofrog points.

Thanks for any answers/advice in advance
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Mountain
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Re: Newbie Here, Got a Few Questions

Post by Mountain »

You do not need feeders for every piece of track, but the basic idea is for all track to be "Live". It does not have to be, as one can simply plug in a DCC controller into a DC layout instead of the DC controller and switch all track sections on. Ok, the sidings will be dead if the points are not set for them, but to be honest, this does not matter unless one wants lights and sound to remain functioning while the loco is sat in the siding.

I will let someone else answer the rest. What scale and gauge do you (Or will be) modelling in?
RowanMackenzie
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Re: Newbie Here, Got a Few Questions

Post by RowanMackenzie »

Mountain wrote:You do not need feeders for every piece of track, but the basic idea is for all track to be "Live". It does not have to be, as one can simply plug in a DCC controller into a DC layout instead of the DC controller and switch all track sections on. Ok, the sidings will be dead if the points are not set for them, but to be honest, this does not matter unless one wants lights and sound to remain functioning while the loco is sat in the siding.

I will let someone else answer the rest. What scale and gauge do you (Or will be) modelling in?
I'm modelling in N gauge, which is why I posted this in the N gauge section lol.

As for track being live, I think the reason for all the feeders was because the tiny N gauge track doesn't transmit electricity well? But if I only need feeders for each piece of track separated by points, that makes my life SO much easier haha
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Bufferstop
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Re: Newbie Here, Got a Few Questions

Post by Bufferstop »

Although just ensuring that each Section of track (by section I mean the track between any two sets of points or any dead end) has power would seem to be all that's needed there are some subtle differences between DC and DCC. With DC you only need to get sufficient current through the track to drive one (two for a double header) loco. On a typical table top layout that requires one feed to one section and you can let the points power any dead ends. If you can't get sufficient current through you turn the knob a bit further and increase the voltage, until you can get the required current (less than around 1amp) through to the motor.

With DCC you may need to be getting three to five amps out to the whole layout so that each loco's decoder is powered and there's enough left over for those that are moving, producing sounds, or blowing out smoke. This means more current flowing through track joints and the point switch blades. These points all exhibit resistance and current through a resistor means heat, heat oxidises the contact points which increases resistance. This is even more important to you as an N gauge modeller, the small contact areas mean more heat even more oxidation, and the small rail cross section doesn't help either. This is bad news.

If two amps can overheat the contacts, you may end up drawing just under the cut out current continuously, especially if a connection somewhere else has all but given up, it's enough to raise smoke from the tips of point blades, making them hot enough to deliver a nasty burn. The answer is to eliminate track joints and point blades from the circuit. It means running more feeds than you could get away with in DC and modifying the links under the points so that they can't short out the unselected exit. A pair of feeds for every length of rail means a lot of feeders so using longer lengths of track avoids feeders for little make up pieces.

I wired my DC layout to allow for an easy transition to DCC, if I ever have the funds for all those decoders, but doing the whole thing in flexi track means the only track joins are at each set of points and it hasn't needed any more feeds than the minimum I could have used for DC, since there aren't that many long lengths of rail.

Personally I blame the RTR manufacturers who seized on and trumpeted about the "only two wires option", rather than the control features which DCC was developed to provide. DCC enables much better control. Manoeuvres like pulling out the stock to release a loco at the buffers, filling the loco yard with nose to tail locos waiting to refuel or sending a banker to help a heavy train on an incline all become possible, even easy, with DCC but it does need more feeds.
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RowanMackenzie
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Re: Newbie Here, Got a Few Questions

Post by RowanMackenzie »

That's really helpful Bufferstop, thank you
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