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mick

Track expansion | Soldered joints

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I've been looking back over some members railways and returned to Crepello's 'Firstlight Railway' where he describes laying his track loose and soldering all the joints - hence there's no need for bus wires or rail bonding. I was wondering if it would work on say, a part of our layout rather than on the whole layout?

It's certainly tempting to be able to lay track and not have any problems with electrical continuity. For me, the worst part of track laying is electrical bonding so I'd be pleased to give that a miss. I'm not so sure about leaving the track loose in order for it to take up any expansion - you'd only need a cat to come along and there'd likely be track everywhere - or would there?

For instance, I've just installed baseboards along the bottom of the garden and the main run is dead straight at 16 feet or so in length. Could I solder all those joints and leave the track loose with just a single feed to each rail?

What's the rate of expansion for a one metre length of Peco track - anyone have any idea?

If that's not a good idea then how about soldering every other joint to make 2 metre long lengths of track that would halve the number of rail bonds required? Would that work okay on straight track do you think?

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Obviously I don't have the experience of others with either the track or signal loss with DCC so take my post with a pinch of salt, but each of my DC loops is 29ft with a single feed each and it runs fine. So in theory it should be fine to do, but personally I like the idea of having the bus wire there for redundancy. Having a dropper on each section of track is going to involve no more soldering than soldering each joint if you use IDC connectors to link up to the bus (I think that's what they're called, image below)

I wouldn't want to lay the track loose either, certainly not with the peco track I have anyway - far too floppy. If I was thinking of laying it loose I would probably opt for something more rigid like the Hornby semi-flexible track. What about just putting in a pin at either end of the track rather than along the length? The joints are the weakest link of the layout so if a member of the local wildlife does get snagged, at least they're protected

60097.jpg

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Nickle silver track expands by 0.0166666666666666666666666etc mm per degree C change, per metre.( if I've got my maths right)

So at a Absolute worst case from say -10C to plus 30C that's a 40 degree Change is .6mm per metre or roughly your 16ft length would expand and contract by 3mm.

A 2 metre length of track would change of course by 1.2 mm for full range but if you laid the track @ 10C, which is quite possible, it would only move by+- 0.6mm.

As for those connectors shown I hate them, I will be soldering each wire into place.

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On the Maths of expansion I wrote this 4 years ago.

It says much the same as above, however my worst case maths is different. Rather than air temperature, I worked from temperature of track when laid, to the temperature track will reach in direct sunlight, which is too hot too touch!

On Sunday I did notice an issue with expansion with one of my rails. The rail had crept in one direction and had to be pushed back a couple of mm too return it to its correct place. Expansion and contraction work together like a ratchet, when the rail expands all the growth is at the left end, the contraction happens at the right end, the effect is that the rail moves a little to the left each expansion and contraction cycle. This occurred on a rail next to a lift out section and the rail was almost damaged when the baseboard was dropped into place.

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Mick, I hope you don't mind me saying this, but you're looking to cut corners in an area where the collective experience of this forum is that you simply can't cut corners. You need to pin your track down and bond/bus every rail.

The idea of soldering the actual joint doesn't appeal to me. I've not tried since I was a teenager, but soldering one rail to the next sounds like it would take a lot more heat from the iron than soldering a thin wire to a rail. The more heat required the more difficult it becomes outside.

If you are using a bus, then solder your dropper wires to your rails before you take them out to the garden. Then all you have to do outside is solder the dropper to your bus.

I've recently removed all of the connectors Shaun mentions from Amblethopre. They weren't up to the job of connecting my solid core bus to stranded droppers. I say all... I had a dead section of rail on Sunday, I traced the problem to one of these connectors, it is joining two length of stranded wire, I'll have to get my iron out again.

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Thanks 'Q' for responding and to Chris for pointing me in the direction of a previous topic which I had failed to locate.

chris said:

Mick, I hope you don't mind me saying this, but you're looking to cut corners in an area where the collective experience of this forum is that you simply can't cut corners....

I don't mind at all Chris because that's almost exactly what I was trying to do! But it's not about avoiding the task of adding bonding wires to each length of track, it was just the idea that if we had longer lengths of track then we would need to add fewer bonding wires which should then reduce the number of potential problems.

Crepello's Firstlight Railway doesn't have a single wire outdoors so providing the soldered joints are sound then there's nothing that could go wrong. Keep the wheels and track clean and it's almost like having a radio controlled railway.

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As someone returning to the hobby after many many years l found all the talk of bus wires, bonding etc very confusing so in typical fashion for me ignored the lot and done my own thing.

My initial section of line, about 100ft total length is still in use and relies on fish plates only for power and now over 3 years old still works. Only now in the newer parts have l started powering individual lenghts of track. Even this is done contary to normal practise by soldering the droppers to individual fish plates alternating +/- at each joint so there is roughly 6 feet between each feed, again no problems.

Only now am l following excepted practise and doing each section of track. As l have no mains power in the garden soldering in situ is a problem and have been trying out some liquid solder which seems to work but does take 12 hours to dry solid so can be a bit fiddley getting wires to stay in place. Wouldn't like to do a solid soldering jib with it though.

So for me fishplates work, droppers work , and if it means l dont have to solder in the middle of a flower bed l am happy. If its wrong l dont mind someone telling me l told you so.

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Mick

On the HFR i bonded all the joints at first, but as some of this shoddy workmanship :lol: started to fail, I became even lazier and just soldered the fishplates :oops: It didnt seem to matter or cause any problems, although I had left some pretty hefty expansion gaps in the ends of the rails - something ive not gone out of my way to do this time. I cannot see that soldering every other, or every 3rd join, would be detrimental. I agree with the others that track definitely needs pinning down, although agan, I only do it about every 5".

I have got some electrically conductive glue from the USA, which I plan to try glueing the bonding wires with, when I get around to it.

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Hi Mick. I know I'm a relative novice to our hobby but in all my years of 'tinkering' with cars etc I find any 'mechanical' means of joining wires should only ever be regarded as a temporary fix. We all lay our track in the hope it will last a long time so I would say solder every wire. Mechanical means of connection will always fail at some time mate. Not trying to teach you to suck eggs or anything that's just my opinion. Regards. Mark

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WOW! all this talk of "bus wires" and "droppers" is it all really necessary? All I have ever done is solder a small wire from the end of each rail to the end of the next rail so that you are not relying on the fish plate to make the electrical connection. I have been running outside for nearly 20yrs now like this with absolutely no problems. :)

With regards to track expansion just leave a suitable gap in the rail joints, you know common sense, not too big, not too small. There has only been a couple of occasions when we have had the track buckle due to the sun, it's not such a big issue as it's usually too hot to be running anyway, but it goes back again when the temp goes down (just like the real thing) :lol:

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EngineDriver said:

WOW! all this talk of "bus wires" and "droppers" is it all really necessary?....

But that's the point I was trying to make. There's a guy running a large scale outdoor line with absolutely no bonding wires whatsoever other than a single power feed to the track in an under-cover location and yet here we are soldering wires to every single piece of track because that's what we've all been advised is the thing to do.

Couldn't we ourselves move from short lengths of track to long-welded (just like the real thing) :lol:

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Yes Mick we could, however you would still need to put an expansion joint in here and there as is done on the real thing. I don't know if you have ever noticed on the railway sometimes you will see two short lengths of rail in the four foot and the rails at that point are cut kind of wedge like so that they can slide along each other as the track expands and contracts the rails in the four foot anchor the thing together, its a bit difficult to explain in words Ill try to find a picture! :)

Expansion-Joint.jpg.d275cb926768d397e1e285c012f41d85.jpg

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Peco do those too, spotted them when I was looking into expansion (SL-44). Although I don't know if they've been discontinued though as everywhere always seems to be out of stock...

sl44.jpg

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mick said:

Couldn't we ourselves move from short lengths of track to long-welded

I've thought for a while that I'd like it if Peco made 6 foot lengths of rail. They would be cumbersome for retail and shipping, but they would be very handy. Being able to do a full curve in one length of track, I can only dream.

Soldering two lengths of track together would be fine, 3 would be OK and so would 4, probably, but after that expansion would start to become troublesome.

I don't see any advantage of soldering rail to rail, over bonding rail to rail. In fact I think bonding would be easier.

Does anyone have any thoughts on what type of solder to use for soldering two rails together. Electrical solder or Brass Kit solder?

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A buying spree over the winter has left me with a large amount of short lengths of flexiable track, 18 inches downwards. Now some short lenghts are away usefull, saves cutting full length track, but l did wonder about soldering some shorter bits together rather than waste them.

I was always told to leave expansion gaps about a credit card edge width between joints which seems to work. But remember it will also depend on the temp when you lay the track. The Goldielocks problem , to hot, to cold and just right. Having said that l've been out doing sone track work today and closing up gaps as l feel its a "just right" day today, time wilk tell.

To end with, how much expansion, contraction will the average solder take anyway before it too fails?

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Lead solder or silver solder. I think that's the question. As far as I know, the harder silver solder needs a torch to generate enough heat to make it flow. I can't see it being viable with plastic sleepers. I am happy as always to be proved wrong.

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I think it was about 10 years ago now, that the EU, China and California banned the use of lead in consumer products and there was a rush to stock-pile "proper" solder. There's still plenty of lead about in car batteries though.

For track connections, I use simple electronic "flux-core" solder which probably has tin in it. Sometimes I use a little liquid flux if it's convenient.

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Sorry, lead solder doesn't contain lead anymore. It's just that I'm old and still use the inches side of a tape measure, so soft solder will always be lead solder to me.

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Hi

The method used on the Great Wakering layout which has proved the test of time (35 years) for th oldest section is lay the track in medium temp conditions allow approx 1/4 mm gap on each joint use fishplates replace the end sleeper of each yard of track with a soldiered paxilon one. Split main line into sections of approx scale 1/4 mile with feeder cable, I isolate both rails. I have then found no problem with using telephone cable to bond accross rail joints which is easy to soldier. On sections of this length I have found no voltage drop and no problems even when double heading and even with running at 1/2 amp consumption with old type motors. All control panels have Volt and Amp meters in circuit and I use feed back type ECM this reduces the extremes of up hill and down hill speed differences. All locos have a maximum Voltage setting appropiate to the type of train and loco with a line maximum of 75 - 80 mph scale speed. Even with the large radius's uses in the garden this is far in excess then the prototype.

My layout will be open again this year so please contact me if you wish to visit.

Trevor Jones

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roddy said:

Sorry, lead solder doesn't contain lead anymore. It's just that I'm old and still use the inches side of a tape measure, so soft solder will always be lead solder to me.

It's lead in my solder!!! I got rolls and rolls of it when the company I work for had to get rid of it and no I'm not giving it away it's so much better than the new stuff. I've got my stock for many years to come!! I've got black / red house wiring stashed away as well!!

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