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New Member
Here’s a question about soldering track work…

I’ve finally laid the entire track down on my layout and have tested it and fixed any “issues” that have appeared and now everything runs smoothly. I’d like to solder the rail joints together but I’m not sure if I should do all of the joints, just the straights or just the curves.

I also don’t want to melt the plastic ties on the track so what temperature range should I use. I have a Weller's variable temperature electronic soldering station with a variable power control from 5 to 40 watts (positions on the dial of 1 through 5 that goes up to 900 degrees F). Where do I set it for best results and what type of solder should I use?

Thanks for any advise

grande man

Bonafied Grande Nut
Curtis, I won't ell you how many joints to solder. I don't know your construction or environmental specifics. I will tell you to make sure the rail is clean and use flux when soldering. Those are important points.


Coal Shoveler
You don't need to do all the joints, you need to allow for some expansion (unless you're counting on that prototypical "sun kink"). If you have feeders every so often, you can solder even less.

Though I would solder most of the curves, just in case the track moves through a heavy handed throttle. That's where some movement could break a connection. Plus, many folks who use flextrack normally solder the entire curve.



Lake Shore Lines
I also agree on the Curves as being the prime place to solder. I also used track gauges on each side of the solder point to disapate some of the heat so that the ties would not melt. I set my soldering iron to about 20 watts. it worked fine.


Registered Member
Staff member
Yes the above advice is the way to go. I read some where at some time in the past to solder all the rail joins on a curve and allow for expansion on the straight. Most of my track ( loops and mainline) is down for about 3 years and I've had no problems with it. Also in regards to the allowing expansion room, I didn't leave any, but during the winter there are small spaces between the rails in the railjoiners (about 1/32" I'd guess) the more unsoldered joints the more room for expansion. I might add this track was put down in the summer time, when humidity is highest, therefor the gaps appear during the winter.
Consideration: I seriously doubt there is all that much expansion in the rails themselves, but the value percentage of the humidity certainly affects the wood, and this is where most movement comes from (my opinion for what it's worth, I found this out when trying to keep the entry gate aligned ) Keep in mind that the more unsoldered joints you have, the more feeder wires to the rails are required to maintain good electrical conductivity.
In regards to soldering (might as well add another) I use a 15/35 watt pencil soldring iron with a chisel tip. When not being used I switch it to 15W, helps the control of impurity buildup on the tip.
The soldering iron tip has to be tinned and clean
The rail or metal parts to be soldered must be clean, (oxyide buildup)
The solder must be of the Rosin core type or a type coreless solder used with Rosin flux (paste or liquid)
In the case of soldering a rail joint I use a riffler file (round or tri corner) to burnish the rail area to be soldered. I then apply a (very) little rozen flux to the area.
When the iron (on 35W) is hot enough to melt solder, I place the chisel tip where the rail joiner meets the web of the rail, I immediately touch the solder to the same area (on top of the tip), as the solder melts I move the tip along the lenght of the rail joiner and remove the tip from the join so as not to transfer any more heat to the rail than necessary.
One last point about oxyidization, the oxyides prevent the solder from sticking, until the heat transfered to the joint is hot enough to burn the oxyides, then the solder will stick. However by this time enough heat has been transfered to the rails to melt your ties and leave a sorry looking mess.
Again, it's just my way of doing it, there are others just as succesfull


New Member
OK, this soldering thing isn’t as easy as it sounds or I’m just a hack. I burnt the heck out of my thumb and melted a bunch of ties on the test track I was practicing on.

Is it really this hard to begin with or am I just using the wrong techniques?

Where do you hold the soldering iron to the rail/railjoiner?

How long should it take before the solder melts onto the rail?

If the trains run fine without the joints being soldered do I really need to do this?

Thanks again for the advice.


Registered Member
Staff member
Did you clean the rail surface and the railjoiner surface then a little flux before putting the soldering tip to the area to be soldered?
Is the iron up to temprature before using?
Is the soldering iron tip TINNED?
What wattage rating is the soldering iron?

>Is it really this hard to begin with or am I just using the wrong techniques? < Don't really remember I've been at it since the early 50's :D Don't think it was very critical then.

>How long should it take before the solder melts onto the rail? < a few seconds seconds or up to 10 secs if the iron is hot enough. I never really timed it. When the solder flows I remove the iron from the area
>Where do you hold the soldering iron to the rail/railjoiner?<
If the rail joiner and the rail surface to be soldered has been cleaned and a fluxed. Touch the tip (point) to the area where the railjoiner meets the rail actually more of the tip touching the railjoiner. Wait a few seconds then touch the end of the solder wire to the tip closest to the rail, the solder should melt quickly and flow along the area that has been treated with the flux.
>If the trains run fine without the joints being soldered do I really need to do this? < Unless it's a really small layout you will have to solder feeder wires to the rails.

>I burnt the heck out of my thumb and melted a bunch of ties on the test track < Ties melting I understand,( I've done it myself) what are you doing to burn your thumb?
The ties melt because they absorb heat from the rail (which has been heated well beond the temprature required to solder the joint)

I'll try to take a couple photos and post them later


grande man

Bonafied Grande Nut
I hate to state the obvious, but the tip of the soldering iron should be below the rail joiner. I find that a little liquid solder on the iron's tip also greatly helps to transfer heat quickly to the joiner/rail.


Registered Member
Staff member
but the tip of the soldering iron should be below the rail joiner
LOL I used to do it that way, but now I never do, I always put the chisel point against the outside rail web. The rail itself will heat just that little bit quicker, the flux takes care of the rest. I find that this method works best for me. :D



New Member
Hey Curtis,

Set your temp setting @ 40 watt. The reason that your ties melt is because you have to heat up your rail joint to long to obtain the right melting temperature of your souder. In the mean time the heat is travelling through your rail destroying the next 2 or 3 ties. The whole soldering operation should not take more than 5 seconds in total.
1. Switch on your solder iron and let it reach the right temperature
2. clean and tin the tip of your solder iron
3. push your tip against the point to be soldered
4. add your solder to the tip, let it melt and flow into the rail joiner
5. remove the solder from the tip and than remove your solder iron from the solder contact point. Do not cool off your soldering by blowing air and/or cool with liquid. This will create a bad solder.!!!

All this should be done in less than 5 seconds.
I hope that this extra info will help you to do the job.

Best regards
Constantin De Bock

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