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Discussion Starter #1
I am considering a building an N-scale layout that surrounds the perimeter of my basement near the ceiling and mounted to the wall.This setup would be very long and would require around 110 feet of track in a giant loop. That being said, how would I wire a setup this long?

I figure for starters it would make more sense to use DCC since a digital controller could keep a constant speed with regards to resistance/voltage drop in the track rails towards the farthest points from the transformer.

Would a basic DCC transformer designed for N-scale be adequate for this length of track?

Forgive my lack of knowledge here, but is a repeater simply additional wire from the transformer connected directly to a further part of the track rail, essentially providing more conductive material (the wire) to decrease resistance and voltage drop? Would repeaters be necessary? How many and at what distance?

Aside from the long track length the setup is as simple as can be... One engine running on a simple loop of track continuously at the same speed and same direction. no sound required, no powered accessories, lights, models, etc, no direction reversing, no track splitting.

On a side note, however, in the future if I ever did decide to add a second engine on the same track so they were always spaced around 50 feet apart, is there a way with DCC to make sure each train maintained a constant speed and distance between each other on the same track to avoid eventual collision?

Please advise. Thank you!
 

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Many would recommend you install a "bus" underneath - a couple of thicker gauge wires to minimize voltage drops along the entire length of the track. Then some "feeders" from the "bus" to the track - thinner gauge wires soldered to the side of the track and attached to the "bus" underneath. How many depends on who you talk to - some say every 3 feet, some say every 6 feet, etc.

With DCC you can run as many locos as you want. If you don't want them to collide then you may have to get into some advanced concepts such as "speed matching". Another way would be to use two throttles (one for each locomotive) and you can dial each locomotive to the same speed.
 

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As has been said run a bus wire and put feeder drops about every 6 feet and you'll be good. BUT, I would give some thought to the N scale idea for a ceiling shelf. Remember your train is only about 1" tall. Probably the most you would see of it is the very top and that only from the other side of the room.
 

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As mentioned, you should put a power bus underneath the track so that you aren't relying on the rail connectivity all the way around your layout. You should run the bus from your transformer or command station half way around the room in each direction. That way your longest wire length is ~52 ft instead of 110 ft. Since you're going such a long distance, I'd probably use 14 AWG stranded wire to minimize voltage loss. As said, run periodic "drop" wires from the track down to the bus.

If you think you'll eventually want to run 2 trains, I would recommend you use DCC. That way the simple wiring described above will work no matter the number of trains. Some DCC throttles can control more than one train at a time. If your trains are only going to run for a couple hours at max, I would think you could dial in the speeds of each to keep them apart. If they are really going to run non-stop without any watchful eye on them, then you would probably want a bit of automation hardware/software that can "keep watch" for you.
 

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As mentioned, you should put a power bus underneath the track so that you aren't relying on the rail connectivity all the way around your layout. You should run the bus from your transformer or command station half way around the room in each direction. That way your longest wire length is ~52 ft instead of 110 ft. Since you're going such a long distance, I'd probably use 14 AWG stranded wire to minimize voltage loss. As said, run periodic "drop" wires from the track down to the bus.
I imagine the drop wire gauge doesn't matter since they're only a few inches in length?

Also, using a bus a described, will that (almost) completely get rid of slow down at the far point in the track if I use DC instead of DCC?

Just curious, hypothetically what would happen if I used DCC so the speed was regulated electronically, and instead of running two 52 ft feeders around the entire track I just ran one feeder to the furthest point and connected it to the track and didn't use any additional drops? Would the voltage remain consistent enough that a DCC transformer/ controller could handle the output and keep the train moving at a constant speed (even though there would be a slight voltage drop around 25 feet out on each side of the loop)?
 

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I am considering a building an N-scale layout that surrounds the perimeter of my basement near the ceiling and mounted to the wall.This setup would be very long and would require around 110 feet of track in a giant loop. That being said, how would I wire a setup this long?

I figure for starters it would make more sense to use DCC since a digital controller could keep a constant speed with regards to resistance/voltage drop in the track rails towards the farthest points from the transformer.

Would a basic DCC transformer designed for N-scale be adequate for this length of track?

Forgive my lack of knowledge here, but is a repeater simply additional wire from the transformer connected directly to a further part of the track rail, essentially providing more conductive material (the wire) to decrease resistance and voltage drop? Would repeaters be necessary? How many and at what distance?

Aside from the long track length the setup is as simple as can be... One engine running on a simple loop of track continuously at the same speed and same direction. no sound required, no powered accessories, lights, models, etc, no direction reversing, no track splitting.

On a side note, however, in the future if I ever did decide to add a second engine on the same track so they were always spaced around 50 feet apart, is there a way with DCC to make sure each train maintained a constant speed and distance between each other on the same track to avoid eventual collision?

Please advise. Thank you!

MoSeS;

I think you will find it hard to see an N-scale train very well when its up near the ceiling. We had another new member packalon, over on the "introduce yourself here" /"New member introduction" section, who had a similar idea. I suggested he move the layout down where he could see, and reach it better. Can you do that? I think you would get a lot more fun out of it, and have an easier time building your layout, and cleaning the track, if it were lower. You might want to check out my discussion with packalon on the "New member introduction section.
The files attached have more info on model railroads in general, and shelf layouts in particular.

good luck & have fun

Traction Fan
 

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Discussion Starter #7
MoSeS;

I think you will find it hard to see an N-scale train very well when its up near the ceiling. We had another new member packalon, over on the "introduce yourself here" /"New member introduction" section, who had a similar idea. I suggested he move the layout down where he could see, and reach it better. Can you do that? I think you would get a lot more fun out of it, and have an easier time building your layout, and cleaning the track, if it were lower. You might want to check out my discussion with packalon on the "New member introduction section.
The files attached have more info on model railroads in general, and shelf layouts in particular.

good luck & have fun

Traction Fan
My basement has a low drop ceiling, only 7ft tall. I already have one smaller n scale setup along my ceiling in the other room in my basement around my bar area (see photo) . With the ceiling being so low the train is very visible. It's a 24 ft loop DC. I pretty much want to create this around the perimeter of the game room on the other side of my basement but this will require 110 ft of track.
20200426_201121.jpg
 

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I imagine the drop wire gauge doesn't matter since they're only a few inches in length?
That's correct. For my HO scale layout, I used 22 AWG wire. You might want to go smaller because of your N scale track.

Also, using a bus a described, will that (almost) completely get rid of slow down at the far point in the track if I use DC instead of DCC?
See this voltage drop calculator: Voltage Drop Calculator If I plug in 14 AWG copper wire, 10V DC, 1A current draw, and 55 ft of wire, it says the voltage drop is less than 3%. I'm doubtful this would be noticeable but my layout isn't that big, so I have no practical experience to draw from here.

Just curious, hypothetically what would happen if I used DCC so the speed was regulated electronically, and instead of running two 52 ft feeders around the entire track I just ran one feeder to the furthest point and connected it to the track and didn't use any additional drops? Would the voltage remain consistent enough that a DCC transformer/ controller could handle the output and keep the train moving at a constant speed (even though there would be a slight voltage drop around 25 feet out on each side of the loop)?
My worry with this plan is more about connectivity of all the track joints than voltage drop. Let's say you're using 3 ft flex track. You'd have about 18 pieces of track to get you 54 ft. That's a fairly large number of joints that all need to be perfect. Its the unreliability of track joints that causes the best practice recommendation of putting track power drops every 6 ft or so. Personally, I think every 6 ft is too conservative, but I wouldn't go more than 10 ft between drops. If you did a drop every 9 ft, each drop would service 3 pieces of flex track. I'd solder the joints between those sections to ensure solid joints. I wouldn't solder the joints between the 3 piece sections to allow for thermal expansion.

I saw your photo of your smaller loop. It looks nice. If your concern is about the wiring being visible, you could actually run it on the top side right against the wall and it probably wouldn't be visible. A bit more complex way to hide the wire would be to put it below the trackbed and hide it with some crown molding. That would look really classy, in my opinion.
 

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Discussion Starter #9
Thanks for the replies! For good measure I'll use feeders with drops on both sides of the loop. The rail joiners possibly causing connectivity problems never occurred to me but it makes good sense. So you recommend leaving say, every third rail joint (with 30 inch sections) unsoldered due to track thermal expansion? I will be using flexible adhesive squares to fix the track to the wood molding so there is some room for movement as well.
 

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One more thought, wouldn't it just make more sense to make the 14awg bus one one continuous 110 foot loop that follows the track? You had mentioned using two 52ft length wires for the bus, but that means they essentially will both terminate at the exact same spot on the track.
 

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So you recommend leaving say, every third rail joint (with 30 inch sections) unsoldered due to track thermal expansion?
Yes, you got it.

One more thought, wouldn't it just make more sense to make the 14awg bus one one continuous 110 foot loop that follows the track? You had mentioned using two 52ft length wires for the bus, but that means they essentially will both terminate at the exact same spot on the track.
Actually, you can leave a 6-9 ft gap between the ends of the bus at the far side away from the power source. So it would take more wire to make the loop than to have two branches, one running each direction. The main thing I wanted to be sure you didn't do is run the bus a single direction for all 100+ ft causing double the voltage drop at the very end. Hope that make sense.
 

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"wouldn't it just make more sense to make the 14awg bus one one continuous 110 foot loop that follows the track?"
Yes, it would. The track does that anyway. The loop in the bus will share the load in both directions from the main track feed, up to the locomotive. So there is actually less voltage drop at the loco. I can't really do the ith calulations but one of the EEs might confirm this. :D
 

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You don't want the DCC bus to make a continuous loop, that will cause real problems.
Go with the two 52 foot bus runs with feeders every 6 to 9 feet.

Even with speed matching using DCC I doubt you could run two trains for an extended time
without them eventually crashing unless they are monitored.

Magic
 

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Yes! I forgot he was considering DCC...:rolleyes:
HOWEVER... The rails themselves already constitute a continuous conductor loop.
I think this has been a somewhat ongoing discussion for years... I'm not sure about the frequency of the DCC modulation, but likely not high enough to cause sync issues or reflectance.
If it's truly an issue then the rails need insulating gaps. I don't think that this is a common practice, related to DCC usage; but I've been wrong before! 😅
 

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Discussion Starter #15
Off topic, but when connecting the pieces with the rail joiners at the joints that won't be soldered, should the rails actually touch or should a small gap be left for expansion and contraction?
 

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Thanks for all of the info, very much appreciated! After some thought I may consider HO, not sure yet. What are your guys thoughts on maintenance / cleaning frequency / mechanical failures with HO vs N? I'd like as little maintenance as possible once finished.

Again, off topic just curiosity here, what are the general thoughts of dead rail in terms of set up, cost, and reliability, and safety with using lipo?
 

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Off topic, but when connecting the pieces with the rail joiners at the joints that won't be soldered, should the rails actually touch or should a small gap be left for expansion and contraction?
Leave a small 1/32 - 1/16 gap between the rails. And as has been said, don't make the bus a continuous loop. Since this layout is going to be above eye level, I would consider having the bus run along the inside corner so it won't be seen. 14 gauge wire should be fine for the bus, and 22 gauge or so should be fine for the feeders.
 

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Off topic, but when connecting the pieces with the rail joiners at the joints that won't be soldered, should the rails actually touch or should a small gap be left for expansion and contraction?
MoSeS;

I would leave about a 1/32" or less, gap between rail ends on straight track, and solder all the rail joints on curves. It's best to solder the two sections of flex track while they are still straight, and then bend them to the desired curvature. Doing this prevents kinks at the joints. The actual rails don't expand, or contract, all that much. What does is the wood they are attached to. Temperature, and especially humidity, changes can cause the wood to warp and expand/contract. Your use of foam tape will allow some flexibility, and that's smart. You might also consider painting all the wood to help seal out moisture.
On your track cleaning frequency question, there would be no real difference between how often you need to clean HO-scale or N-scale track. They will both need periodic cleaning. A rag, damp with alcohol, usually does the trick. You might also use a track cleaning car with a piece of Masonite dragged along under the car to help keep the track clean.

Traction Fan 🙂
 

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A common misconception about our tiny rails is that they expand and contract. And they do, but it's a really tiny amount: 0.000009 inches per inch of track for each degree farenheit change in temp, or 0.012" per degree for your entire 1320" of planned track.. If your basement has a 10 degree change in relative temp, that's less than an 8th of an inch over the length of the layout. Not really worth bothering with. A couple of 1/32" gaps over the whole thing will cover that.

What WILL kill you is wood that is not sealed. That can swell (or shrink) 10-15% with a 10% change in relative humidity. Any track rigidly fastened to that wood will move, with often disastrous results (one advantage to using latex caulk as an adhesive is that it flexes, and can absorb some of that movement). Seal the wood -- varnish the shelves -- and use a dehumidifier and you won't have any trouble there, either.
 

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MoSeS;

I think you will find it hard to see an N-scale train very well when its up near the ceiling. We had another new member packalon, over on the "introduce yourself here" /"New member introduction" section, who had a similar idea. I suggested he move the layout down where he could see, and reach it better. Can you do that? I think you would get a lot more fun out of it, and have an easier time building your layout, and cleaning the track, if it were lower. You might want to check out my discussion with packalon on the "New member introduction section.
The files attached have more info on model railroads in general, and shelf layouts in particular.

good luck & have fun

Traction Fan
 
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