Should I use dropper wires for this simple layout?

[simplealec]

I have a shelf layout which consists of one large (15'x11') oval with passing loops in the straights.

Since the layout goes around the walls, there is no shorter path for a bus to follow; the furthest point from the controller will be about 26' with or without a bus, so there is no physically shorter path for the power to take.

I understand that power can be lost over track connections (fish plates), however I imagine this can be negated by soldering these joins, which I'm happy to do since this is a permanent layout.

Would it still be beneficial to run a power bus with droppers in such a layout? Would 26' of cable have less resistance than 26' of track, even assuming soldered fishplates? If so, please direct me to a source of info on what type of cable I should get.

I don't know if this is relevant but I'll provide it anyway: the layout is DC with insulfrog points, OO/HO scale.

[Roger (RJ)]

Do not solder the fishplates!!!!! This will almost certainly cause it to buckle as it gets colder and warmer. The fishplates allow the track to contract and expand.

A bus of an appropriate sized cable will conduct electricity far better than the track.

Is this a dc or a DCC layout?

[simplealec]

Ah, didn't know that about fish plates. That makes me somewhat concerned that I've already laid the track without gaps for expansion, although I did so in late summer so it's not likely to get much warmer. I'll deal with that problem if/when it occurs, it's not a scenic layout so no big deal if there are issues down the road. The railroad. Ha.

What's an 'appropriately sized' cable? Layout is DC.

[Bufferstop]

Putting in effective expansion gaps can be a problem. Try to avoid long straight runs, rigidly pinned down. I only pin down hard at points, in between I lightly pin, ballast, then pull the pins. If there is just a very slight curve any expansion pushes the curve out further. The ballast may crumble, but an occasional refresh and application of diluted pva is easy to do.

[simplealec]

Try to avoid long straight runs, rigidly pinned down.

Ah. Aside from the four 22" radius corners, my layout consists entirely of roughly 80' of straight track. It's not ballasted as it's on a shelf about 6'6" from the floor to avoid head bumps, so you can't even see the trackwork other than in profile. I glued it rather than pinned it, as I find track pins awfully fiddly. Also, there's a layer of craft foam between the track and the shelves to dampen the noise. I reasoned that gluing the track to the foam (which is itself glued to the boards) would prevent vibration being carried to the boards through the pins, whilst still holding the track firmly in place.

Now this all being said, it's only your standard PVA/water/dish soap mix, so a wallpaper scraper soon has it up again without damage to the track. But since the layout is not at all scenic but rather a glorified display cabinet with continuous running, it might not even matter if some subtle kinks occur in summer.

[pete12345]

If you've left expansion gaps it shouldn't be a problem, and laying track in hot weather is the safest option.

I alway recommend wiring to each piece of track separately, placing no reliance on rail joiners for conductivity. It's a bit more time-consuming for sure, but once it's all laid and wired then it will be much more reliable. Lay each piece temporarily, mark either side of the rails with a pencil, then lift the track and drill between the marks- leaving a hole directly under the rail. Wires can then be soldered to the flat underside of the rail after removing the sleeper webbing, and once ballasted it is totally invisible. Much better than the usual blob of solder stuck to the outside of the rail!

[Dad-1]

Hi simplealec,

Droppers, Droppers, Droppers.
Every piece of track on my layouts have droppers onto a bus wire.
Even 32 mm long filler pieces. On one of my small layouts the tracks
are about 8 feet & 2 points, It has 14 droppers !!
All soldered onto the underside of rails, never to fishplates.

Geoff T.

[RAF96]

If you want to use the track as your bus, try Omega Ω loops soldered across the rail joints on the outside. Not particularly pretty but if out of sight then out of mind. These allow expansion and contraction and bypass any loose fishplate problems.

[gppsoftware]

In answer to the OP's original question, irrespective of whether the layout is DC or DCC, its size is such that it will benefit from a bus. I would be installing bus(es) if it was my layout.

The OP indicated that the layout is DC, so if a second loop is installed in the future, a separate bus will be required for it - this was how I originally built Ashprington Road (http://www.mrol.com.au/Pages/Vu/AshpringtonRoad) as a DC layout. When I converted it to DCC about 15 years ago, I replaced the two bus cables with a single 10A mains rated cable and connected everything from both tracks to it.

I have an article here about installing buses: http://www.mrol.com.au/Pages/Vu/Wiringa ... ctricalBus

As others have indicated, DO NOT solder fishplates.

In my part of the world (Australia), track laying is usually best done in the summer months when rails have expanded. Then they contract in the cooler months to reveal gaps at joints. Practice teaches what gaps sizes are required if laying track in the coller months.

I have an article here about installing droppers: http://www.mrol.com.au/Pages/Vu/PowerFe ... thDroppers
Key 'takeaway' here is to always attach droppers to the middle along their length so that equal expansion is permitted either side of the dropper which acts as an 'anchor point'.

And please do avoid those ghastly looking solder globules that seem to pervade so many layouts! : http://www.mrol.com.au/Pages/Vu/Avoidin ... lesonRails