Soldering Techniques?

[jim currie]

i don't solder to the sides if the rail i drill a #64 hole from the top of the rail down and run a #20 wire up through till its just below rail top and solder it , though i will add i use code 100 rail , as for rail joiners i sloder most of them but do leave a few unsoldered.
jim

[Russ Bellinis]

The main thing with solder is it should not be "globbed on." The most critical thing about solder is that the parts you are soldering together must be clean and shiny before you try to solder, then use a thin coating of rosin flux on both pieces in addition to using rosin core solder. Drops should be single strand, solid wire only because a multiple strand wire will be too big. I would make an attempt to solder a drop to every piece of rail, but if you have a short section of rail, like a 1-6 inch piece of snap track to fit a spot where your flex track was just too short to complete the space, but you didn't want to cut off a short piece of flex to reach, it would not hurt to either solder the rail joiners to make the flex track 1-6 inches longer, or I think the preferred method would be to bridge the joint with a wire from one rail on the flex to the corresponding rail on the short piece. By the way, I don't worry about melting a few ties when soldering. They are easily removed after the rail is soldered. I save extra ties left over from cutting the flex track to length, and I also bought a box of Campbell wooden ties a few years ago and stained them with Minwax teak stain which is pretty close to new creosote tie color. I cut off the spikes on the plastic tie strip pieces and just slide them under the joint or slide the wood ties under the joint. Once ballasted, the replacement ties are invisible.

[tetters]

Speaking of track feeders.

I good trick I learned recent is to take your 20 or 22 gauge solid feeder wire and bend a short piece of it at a 90 degree angle near the end. Then squish the end with some smooth jawed pliers. The idea is to get a feeder that looks like a small track spike. To install it drill a small hole through one of your ties as close to the rail as you can get it (either inside or outside) and drop your feeder through. Once installed and painted the feeder wire looks just like a spike head. I've been using this method on my handlayed stuff and the feeders are hardly noticable.

If you are worried about heat melting your flex track ties and to speed up the whole process to minimize the heat transferred pre tin the feeder a good flux (I use an Acid Flux, I just clean and neutralize it with some Iso Alcohol when done) and use some metal clamps for heat sinks. Some cold wet paper towels laid as close as possible to work area also help avoid any plastics melting.

[MountainMan]

Another trick I have seen is to drill a hole through the road bed just inside the track and add the feeder wire. once ballasted, it is invisible from viewers.

[Selector]

Note that "expansion due to temperature changes" in nickel silver rails accounts for about 15% of the changes we see when our tracks buckle. The heavy preponderance of the buckling effect is due to changes in humidity and the resultant expansion of the cells in the woods we use to construct our layouts. In fact, the expansion is actually due to the rail lengths being pulled away from each other as the wood loses humidity and shrinks. When you see your track gaps widening, it is because the wood has regained some moisture content and had lengthened....thus taking the rails apart from each other. Think about the randomly distributed raisins in bread dough as it rises. As the dough expands, the raisins move further apart since they have no motive power of their own.

It was demonstrated to me mathematically on another forum that N/S rails expand very little over swings in temperature of even 30 degrees. The person proved that a contiguous length of 100' of Code 100 (meaning one monolithic rail length of 100') would expand a whopping 1/4" along its length over a rise of 30 degrees. I suspect that we all have an accumulated total of 1/4" in gaps along our track systems, and that those gaps really comprise a total more like 1/2 - 3/4" on a typical layout. So heat is not the problem...humidity is the problem.

Solder the tangents rarely, and solder the curved lengths often...to get good curves. Let the tangents slide in non-soldered joints to help your system withstand the ravages of humidity.

-Crandell

[Russ Bellinis]

Note that "expansion due to temperature changes" in nickel silver rails accounts for about 15% of the changes we see when our tracks buckle. The heavy preponderance of the buckling effect is due to changes in humidity and the resultant expansion of the cells in the woods we use to construct our layouts. In fact, the expansion is actually due to the rail lengths being pulled away from each other as the wood loses humidity and shrinks. When you see your track gaps widening, it is because the wood has regained some moisture content and had lengthened....thus taking the rails apart from each other. Think about the randomly distributed raisins in bread dough as it rises. As the dough expands, the raisins move further apart since they have no motive power of their own.

It was demonstrated to me mathematically on another forum that N/S rails expand very little over swings in temperature of even 30 degrees. The person proved that a contiguous length of 100' of Code 100 (meaning one monolithic rail length of 100') would expand a whopping 1/4" along its length over a rise of 30 degrees. I suspect that we all have an accumulated total of 1/4" in gaps along our track systems, and that those gaps really comprise a total more like 1/2 - 3/4" on a typical layout. So heat is not the problem...humidity is the problem.

Solder the tangents rarely, and solder the curved lengths often...to get good curves. Let the tangents slide in non-soldered joints to help your system withstand the ravages of humidity.

-Crandell

Our modular club set up for a show in an indoor mall under a sky light a few years ago, we had one member who insisted that we didn't need to leave gaps in the rails at the joiner tracks between modules. He was in charge of the set up that weekend, so he cut all of the joiner tracks to fit precisely between the modules during set up on Friday night. Saturday morning as the sun came up it was shining from the East through the skylight on the West side of the layout and the rails on that side started kinking. We had to remove all of the joiner tracks and cut them shorted to allow for rail expansion. By noon we were doing the same thing to solve the same problem on the ends of the layout and shortly after noon we were doing the same thing on the East side of the layout. The humidity did not change, and I'm sure we had more than 1/4 inch of expansion. The space was air conditioned, but we did get some solar gain, although the skylights were tinted a bit. I doubt if there was a 30 degree increase in temperature, but I didn't measure the rail temps.

[MountainMan]

Both temperature and humidity cause expansion, depending on the materials. Next time you drive over a bridge or on a concrete surface, notice the number and placement of the expansion joints. Concrete and steel are unaffected by humidity, but respond to temperature variances. You will also see expansion joints in brick buildings, as well.

I'm surprised that one of our more technically advanced members hasn't figured out a way to measure the expansion in his layout using altered conductivity or something.

[Russ Bellinis]

Both temperature and humidity cause expansion, depending on the materials. Next time you drive over a bridge or on a concrete surface, notice the number and placement of the expansion joints. Concrete and steel are unaffected by humidity, but respond to temperature variances. You will also see expansion joints in brick buildings, as well.

I'm surprised that one of our more technically advanced members hasn't figured out a way to measure the expansion in his layout using altered conductivity or something.

I can't speak for other parts of the country, but a layout inside a building here in So Cal without some sort of skylight to allow for solar gain, just won't change that much. It will see temp changes if the building is uninsulated and not heated or cooled, but in a temperature controlled space, the temperature swing will probably be less than 20 degrees, and our humidity stays around 10% year round. On a really humid day we may get all the way up to 20%.

[doctorwayne]

I have just under 200' of mainline in service, not including double track, passing sidings, staging tracks, and industrial sidings. All of the rails have been soldered together, and where gaps have been cut for electrical purposes, a piece of ABS plastic has been cemented into the gap with ca. I've had no issues whatsoever with expansion or contraction buckling the tracks, probably due to the relatively constant humidity and temperature in the room, which is neither mechanically heated or cooled.

Wayne

[MasonJar]

I'm surprised that one of our more technically advanced members hasn't figured out a way to measure the expansion in his layout using altered conductivity or something.

Interesting challenge! I don't know how to even start this, but I do have some observations to add, based on the modular group I belong to, and other layouts I have seen.

The modular group uses styrofoam decking in a pine or plywood frame. Modules are subject to differing storage and transportation conditions, but remain relatively unaffected - the transportation causes far more problems than humidity or heat do. I am thinking that's because:

- The track is laid on styrofoam for the most part. Styrofoam is unaffected by either moisture or heat.
- The individual lengths of modules is 4 feet. Even if the frame expanded due to humidity (wood being relatively unaffected by temperature), it's only over a 4 foot length, and the frame would have to pull away from the foam to which it is solidly glued. Plus the wood is painted with several coats of paint, inside and out, before installation of the foam. Paint can act aas a moisture barrier.

At home layouts, I think a fair assumption is to say that most of us want to spend the money on the trains. So buying the best lumber is maybe not on the radar, and the benchwork is put up as quickly as possible in order to get to the "good stuff". Wood available at the big box stores may not be dry, and may be affected before building by where it's stored. Once built, how many of us paint/seal all the benchwork before moving on? Sure, the top of the uppermost level gets covered, but a lot of moisture gets slopped on when doing scenery too. Add to that that many layouts are in the basement, which sees the most humidity (if not temperature) swings and it is not suprising that we think the track has moved.

Andrew

[eightyeightfan1]

I'm surprised that one of our more technically advanced members hasn't figured out a way to measure the expansion in his layout using altered conductivity or something.

Someone could do like they do on Mythbusters.
Experiment with different types of track such as brass, steel, nickle silver, with different gauges, on different types of roadbed at different levels of heat, cold and humidity. Take measurements and analyze the data.



Then blow it up!

[tetters]

I had an expansion problem last winter with some of my handlaid track. I quickly figured out what had happened though and it kind of made sense.

The first batch of track I laid during the dead of winter I think I started in late December or early January, furnace going full bore, nice and toasty in the layout area of the basement. So throughout the season, spring, summer and fall no problems. Everything stayed in guage on the exisiting trackwork and worked just fine. That same year I got a jump on things and started spiking track down before we started using the furnace to keep the house warm. We had an unusually mild start to our winter last yeat, but by December I noticed after a few nights of the furnace consistently kicking out the heat the newly laid track had gone all squirrelly on me. It had expanded so much it even distorted (pushed in) some of the PCB ties on my turnouts and closed the isolation gaps at the frog creating dead shorts. I even left tiny gaps in between rail sections which was obviously not enough wiggle room in order to allow this effect to take place. Meanwhile the first laid areas of trackwork saw no such change, remained in gauge and did not appear to expand at all. So while I have started spotting turnouts and such for my new trackwork, I'm going to try waiting a few more weeks and allow the house to "warm up" a bit first and see if my little theory is right.

[MountainMan]

Both temperature and humidity cause expansion, depending on the materials. Next time you drive over a bridge or on a concrete surface, notice the number and placement of the expansion joints. Concrete and steel are unaffected by humidity, but respond to temperature variances. You will also see expansion joints in brick buildings, as well.

I'm surprised that one of our more technically advanced members hasn't figured out a way to measure the expansion in his layout using altered conductivity or something.

I can't speak for other parts of the country, but a layout inside a building here in So Cal without some sort of skylight to allow for solar gain, just won't change that much. It will see temp changes if the building is uninsulated and not heated or cooled, but in a temperature controlled space, the temperature swing will probably be less than 20 degrees, and our humidity stays around 10% year round. On a really humid day we may get all the way up to 20%.

Same here - humidity in the 20's is a soggy day. Ambient temps of 100 or so, however, are not unusual at all.

[Russ Bellinis]

Our temps will occasionally drop to the upper 40's at night in the winter, but typically they stay around the mid to high 50's in the cold season. I the summer, we occasionally see temps of 100 degrees, but usually no higher than high 80's. Most of the summer our highs are probably 80-85, in winter from 60-75. 50 miles inland and the temps are more extreme, but seldom below freezing, but with a few more days above 100.