Although someone briefly mentioned it above, I didn’t see any emphasis on tinning the rail. It really makes the rest of the job go much easier. Here are the steps I go through:
Apply a small amount of flux to a small surface of the side of the rail.
Apply flux to the tip of the iron.
Apply a small amount of solder to the tip of the iron and wipe the tip on the damp sponge.
Touch the solder and the tip of the iron to the side of the rail where the flux is. Remove both immediately after the solder melts, which should happen in about a second. The result should be a smooth and shiny layer of solder on the side of the rail.
Tin the end of the wire and place/clamp it so that it leans against the side of the rail where you have tinned the rail.
Apply a small amount of flux to the assembled joint.
Apply flux to the tip of the iron.
Apply a small amount of solder to the tip of the iron and wipe the tip on the damp sponge.
Touch the tip of the iron to the joint just long enough for solder to melt and flow. It should happen in about a second. The result should be a shiny layer of solder smoothly blended over the wire and the rail.
Another possible problem is the type of tip on your soldering iron. I participated in a couple of threads three years ago in this forum on the relative performance of iron tips and copper tips. You can find these by doing a search on “solder tip question” in Model Railroader Forums.
For better than 40 years now I have never soldered wire directly to the rail, I “always” solder it to the bottom of the rail joiner instead. I can take a group of rail joiners to the work bench, solder them up and have enough to last for several days of track laying at one time.
I also use a “small” torch or my soldering “machine”, something I learned as a result of soldering on brass engines.
And, I only use “Tix” solder and flux, a small bit of Tix flux, then the heat and it flows beautifully and it’s a very strong bond.
The soldering gun and the “Home Depot” solders I reserve for using on the wiring such as the feeders or most any under the table soldering.
The main thing is I solder it to the rail joiners, haven’t melted a tie since I started doing it this way.
I’ve made a lot of progress when it comes to soldering. When I started out about 5 years ago, I made the worst looking solder connections you could imagine. I was in HO Scale then, and I thought I had to have big globs of solder using heavy duty wire. The solder I used was some old acid base stuff (really big sized), and I didn’t even use flux. Flash forward to today, and now I’m using a Weller station with rosin 60/40 solder. Just recently, I started using rosin flux. I had been using an old flux that we had bought about 20 years ago. It turns out I think it was acid base although I’m not sure. I might have some rail connections turn white in a few years but by then I’ll be on to another layout. The layout I’m working on now is Layout 3, and even with the mistakes I’ve made on it, it is still much better than the previous two layouts I have built.
An alternative to soldering the feeder, or even just the joiner to 2 sections of track, is to use some of the Fast-Tracks copper clad PC board crossties. They are pre-gapped so they don’t create a short.
I remove one or two of the flextrack (or turnout ties) at a rail joint, insert a PC board tie aligning the inside of each rail with the gap in the cladding. I then apply my solder to the tie at the joiner. You can also include your feeder wire, or solder it separately to the underside to the tie before installing.
You avoid melting ties (although I still apply a heat sink) and avoid creating a high spot where the joiner would have rested on the plastic ties. Lastly, you maintain the track’s gauge as the gaps in the PC board ties match the NMRA clearance dimensional standards.
The purpose of flux is to remove corrosion on the surface and let the molten solder touch clean metal. As the soldering iron heats the work, the hot metal starts grabbing oxygen molecules out of the air and forming a coat of unsolderable oxide. The flux counter acts this and keeps the surfaces clean, long enough for the solder to adhere to the metal.
They make acid flux and acid core solder. These are for plumbing work only. Never use acid flux for electrical work. The acid stays active, and is strong enough to corrode small wires thru given a few years. Always use rosin flux. The rosin flux is only active when it is hot and melted. Cool and solid, it doesn’t corrode stuff, or at least the corrosion rate is a whole bunch less than acid flux.
The flux lets the solder wet the work. If the solder beads up into little ball shapes, the work is dirty or oxidized and the solder isn’t making contact with bare metal.
Always use 60/40 tin lead solder. 60/40 has the lowest melting point, about 190C, or twice boiling water. Hot enough to melt plastic.
Avoid 50-50 solder, that’s only for plumbing. The recent anti lead phobia has resulted in a lot of “lead free” solders. I don’t trust them. Tin lead solder has been around for thousands of years and it bonds well and stay bonded.
The tip of the iron or gun MUST be tinned. That means covered with a silvery coat of melted solder. Keep a damp sponge on the bench to wipe the hot tip on and keep it bright. If the tinning wears off or burns off you must renew it. Or replace the tip.
When a well tinned tip is pressed to the work, the melted solder flows to the work and makes a solid connection that will flow huge amounts of heat. If the tip looses its tinning, it takes forever to get the work hot enough.
I use a temperature controlled station with a heat indicator. When the control shows that the iron has reached the correct temperature, I always allow five minutes before tinning the iron. This ensures that the temperature is correct.
O.k., I spent all day working on the layout, mostly soldering. I tried a variety of techniques. This post is somewhat lengthy due to all the steps involved in the two methods I tried today. First, I got out my old soldering gun. It is 100/140 watt. At 140 watts, I waited until the gun heated up and tinned it with some solder. Then, I cleaned the tip with the sponge that came with my Weller station. I applied the tip of the gun to one side of the wire that I was going to use as a feeder and the wire instantly heated up. The solder melted without the need of any extra flux. I cleaned the spot on the side of the rail where I wanted my feeder. I then applied the tip of the gun to the place where I wanted the wire and applied solder. The rail heated up and melted the solder without melting any ties. Then, I applied a tiny amount of flux to the cooled off solder. I then placed the tinned wire right up next to the solder & flux on the side of the rail. Then, I applied the gun to the top of the rail and the tinned wire and solder/flux on the rail melted and fused together. I held the gun on long enough to see the solder on the wire and the solder/flux on the rail boil, melt, and fuse together. I did not have any ties melt. At first, I thought I had found a better way of making feeder connections (almost identical to the methods recommended by most model railroaders), however upon inspection I noticed the solder was a light white color (cold solder appearance). I waited a few seconds and reapplied heat and ended up with the same result. I tried the same technique on a rail joiner to see how the gun would handle that. I applied a small amount of flux and touched the tip of the gun to the top of the rail joiner. I then applied solder to the joiner, which melted after 1 second. The problem this time was the rail turned dark brown/black and even melted a few ties. The solder dried a white color. So, I went back to my Weller Station and used my original method. I stripped the wire and applied a small
Think that was me… You could use the same method with 14awg wire, but… You would certainly get much better results using an 80 or 100 watt iron. I used to work for a telephone company as a summer hire. I spent a whole summer back in the 1960s soldering telephone line connections inan x-y office in Victor, NY. For that we used very large, very hot irons to do the job even with 24 or smaller wire. The wire was wrapped around a flat connector, then the iron was placed on one side, and the solder was touched to the other side. Again the joint was always good and done very quickly. But… There was nothing to melt so a lot of heat meant very quick and good work. Personally I would not use a solder connection on very large wire in the first place. If you must, that is the time to bring out the heavy artillery.
The technique I was talking about (which I see you found works well…) I use for small electrical connections like soldering on Tortoise Machines (where too much heat can damage the machine), toggle switches (where the same is true), Spade lug connections to small wire (where it just is the easiest way), and for rail connections with drop feeders for power (without mel
howmus, o.k., so you mostly use this technique as a secondary option when it the normal technique of heating the object poses a risk of melting surrounding parts such as the ties or the plastic parts on a tortoise switch machine. However, you use the regular method on devices where there is no risk of melting anything nearby. That sounds reasonable as I simply cannot make a good solder joint on track without melting the ties using the regular method of heating the rail and allowing it to melt the solder on its own. The picture you posted of your solder connection looks very close to the connections I make. I don’t think that mine are as flowed out as your photo but they’re very close. I definitely don’t end up with any balls of solder that are easy to pry off. I used to end up with balled up solder when I first got back into the hobby in 2004. Also, I mentioned earlier that the solder I used to use was acid base. It turns out that it was rosin core solder that was very large in diameter and was very old. However, the flux I had been using up until a few weeks ago had zinc chloride in it, which I think is acid based. I’m using rosin flux now. When I think about it, I don’t understand why the hot solder hitting the rail and flux would not create a good joint due to the fact that the solder has sat on the iron for several seconds and is already heated well beyond its melting point. When the ball of molten solder leaves the iron and flows into the flux on the rail, it should carry enough heat to heat the rail to a very hot temperature long enough to make a good connection. I could see how this wouldn’t work with large wire such as 14 or 12awg due to the fact that a small drop of hot solder would not have enough heat on its own to heat the entire section of wire to a hot enough temperature to make a good solid connection. Of course with wire connections, one is not really concerned that much with melting anything; the insulation can simply be taped or patched using liquid electrical tape.
For the most part I agree with what howmus said, I just want to add a few lessons I’ve learned along the way:
I started life as an audio technician back in late 60s /early 70s (my first paying job was assembling Heathkits, for those those that remember them). Rosin core solder was developed for the electronics industry to solder components (resisters, diode, etc.) to circuit boards where you need very little solder/flux, but for anything bigger you must use external flux; paste or liquid, it cleans the oxidation and pre-wets the surface so the solder won’t bead up and helps the solder to flow, (just like ballasting track, you pre-wet the ballast with alcohol or detergent/water so the glue won’t bead up).
I was also taught in electronics school never to use more heat than the job requires, a 25 w iron for circuit board work, 40w for up to 18g-16g wire (or up to code 100 rail), 100w or more for wire larger than 16g and always flux and pre-tin wires. Copper wire and brass should be tinned, surfaces that are nicklesilver (like rail) or nicklesilver plated do not need to be pre-tinned, nor do they need any other pre-treatment such as cleaning with a wire brush or alcohol (unless they are visibly dirty), the flux will do all the cleaning that is needed to make a good joint. You can be generous with the flux, but don’t forget to clean all solder joins with a toothbrush and alcohol after soldering is completeted as paint won’t stick well to it well.
Care & Maintenance of soldering tips. This is probably the most important part of making good solder joins. The last half inch or so of the tip should always be shiny silver, if there is any discoloration or blackening (carbon crud) it needs to be cleaned. A damp sponge wil
The flux that is in the solder just isn’t enough flux, if you pre-load the tip (which is what I do) then the flux that was in the solder has already evaporated and burned up, so you need to add the flux at the joint.
“I don’t understand why the hot solder hitting the rail and flux would not create a good joint due to the fact that the solder has sat on the iron for several seconds and is already heated well beyond its melting point. When the ball of molten solder leaves the iron and flows into the flux on the rail, it should carry enough heat to heat the rail to a very hot temperature long enough to make a good connection.”
It should. Once you touch the rail with the iron, you still need to keep it there for a second or two so the rail can get up to the same temp as the solder for the join to complete. Even if you pre-load the tip you may still have to add more solder at the joint. If you didn’t get enough solder on the joint the first try, let it completely cool off before reheating and adding more solder.
So basically it is fine to pre-load the tip with solder, but I need to make sure and use flux and let the iron stay on there for 1-2 seconds to bring the rail up to the temperature of the solder. There are a few things that I am going to immediately change about my soldering method. First, I’m going to replace the original screwdriver tip on the iron with a small pen shaped tip. Believe it or not but I actually ordered a cone-shaped replacement tip about a year ago because everyone recommended getting away from the large screwdriver tip that I’ve been using. However, I ordered the wrong one, and it was hollow inside. What it did was build up a tremendous amount of heat near the handle of the iron, which got so hot that the metal rod extending from the handle started to turn clear where I could see the coil running inside the iron. In addition, that part of the iron turned an ugly purple/black color. I immediately took that tip out of there and went back to the original. I’m going to try and get the right one this time. Also, many people have recommended using 60/40 solder in the smallest size possible. I’ve been using .032 diameter, but a friend of mine uses solder even smaller than that for N-scale. Also… I’m going to try the wet cotton ball technique of placing two wet cotton balls on both sides of the soldering location. One final question: So basically it’s o.k. to pre-load the tip as long as one uses extra rosin flux and holds the iron on there for 1-2 seconds. Now, my question is, I’ve been pre-loading the tip without holding it on there for any length of time at all because I’ve been afraid of melting ties. Are my joints likely not strong enough (cold joints)? Can I simply re-heat them to fix this or should I not worry about it?
I use Radio Shack .022 diameter (62/36/2) rosin core Silver-Bearing solder. There’s a little silver in it to make it stronger and it will not corrode over time. It’s made for electronic circuitry, but it works great on track and just about anything else. The thin diameter heats up quickly and gives you more control, (you don’t end up with big blobs where you don’t want them)
Another tip on stabilizing the wire so you don’t need the “third” hand, after inserting the wire thru the hole in the benchwork if the zig zag bend doesn’t work just wedge something in the hole to keep the wire from moving.
Here’s my process:
Add a little dollup of flux where I want it and then position the wire against the rail so I’m all ready to solder. I extend about 3 or 4 inches of solder from the roll, give the iron a wipe on the sponge and then touch the solder to it, feeding about 1/4" to 1/2" (of the solder wire) to the tip (the pre-load), enough to get the join started, (but you don’t want a big blob on the iron). Position the solder right up by the joint (but not touching) and then bring in the iron and touch the joint, as the flux starts to sizzle (about a second) feed about 1/2’ of solder into the joint right where the iron is touching the joint, pull the solder away keep the iron on there for another second or so and pull it away. You should be able to do it on a count of four. One (touch with the iron), Two (add solder), Three (remove solder), Four (remove iron), total time about 2.5 - 3 seconds. (My quantity (in inches) of solder is based on the .022, if you use .032 use a little less). Practice this with the count and you should get the hang of it, oh yeah, start the count once the iron touches, not before. For practice, pull a couple of inches of ties off the track, do the routine several times with just the counting, don’t worry about the actual time, it’ll get faster as you get the hang
I went to my local RadioShack store today and bought the smallest size solder I could find. I bought 62/36/2 Silver-Bearing Solder at .015" diameter. It doesn’t say whether or not it includes rosin flux; I assume it does. If it doesn’t, can I just rely on the external source of flux? Also, I bought the RadioShack Tip Tinner and Cleaner. It’s a little small metal container with a metal lid that pops off. Also, I’m going to order a new tip for my soldering iron. The conical tip I ordered a year ago was ST7. I didn’t mention this earlier, but the only way I can avoid building up a massive amount of heat near the handle with it was to reduce the heat to the 1-2 setting (approx. 10-15 watts). That obviously wasn’t enough to get the job done. They make two other pencil shaped tips for my soldering iron, ST5 and ST6. I’m going to try ST5. Here’s a question. My soldering station is between 5-40 watts. If I replace my screwdriver tip with a pencil shaped tip, what setting should I have the iron set to between 1,2,3,4, or 5?
I just ordered the ST6 tip instead of ST5. According to Weller’s website, the ST5 tip has a flat top, whereas the ST6 tip has a screwdriver top. I figured that would be better. The diameter of my current tip is .187", and the ST6 tip is .031" in diameter. Hopefully it will do a much better job.
O.k., just to be on the safe side I went ahead and also ordered ST5. I’m throwing everything I have at this; hopefully once the tips arrive, I’ll be able to finally do some good soldering.
I went to the RS site and did not see anything about flux in the solder. When I have used the same solder I dipped it in a little RS flux before soldering. Since the solder is in paste form, I put the iron tip in the flux and melt a little into a puddle. I have some RS liquid rosin flux but they stopped selling it.
IMPORTANT, practice with scrap track/wire. Remember, new does not always mean clean and ready for soldering when it comes to track or copper PC boards unless the PC board was already plated with a solder film. Develop a technique that gives you the results you want.
I use a Scratch Brush from Micro Marks to clean a spot of the track for soldering.
Anyone tells you soldering is easy, they have been doing it for sometime. Also applys to those who tell you that you do not need all the stuff I mention.
The Tip Tinner and Cleaner you got is the right stuff, thats what I use, It used to come in a can about twice that size, anyway, I stick it right to the top of my soldering station, (there’s foam tape on the bottom of the can). Tinner/Cleaner is essential for good soldering.
Don’t stick the the iron in the flux, that’ll start to build up crud on the tip. Instead, to start a soldering session, let the iron get hot, (with code 55 rail try setting 4), then dip the tip in the Tinner/Cleaner, (the stuff is hard like soap), let the tip melt it’s way to the bottom of the can and give it a couple of twists and wipe it off on the sponge, melt a pretty good glob of solder on it and put it back in the Tinner/Cleaner, twisting it again and then wipe off the extra solder with the sponge. If the solder is evenly distributed around the tip and nice and shiny, your tip is properly tinned and cleaned, if not repeat the process. As you use the iron, areas on the tip will start to show black and/or the solder beads up on the tip instead of flowing on, it’s time for a quick dip in the cleaner and a wipe on the sponge. Allways wipe the tip on the damp sponge before and after each solder joint.
Forget about flux in the solder, as long as it doesn’t say Acid Core. What RS sells is all electronics solder, so it is either rosin core or solid core (no flux, we apply the flux to the work anyway, so it doesn’t need to be in the solder). both of which are fine for our purposes. You only have to be concerned about the core when you buy solder at hardware stores where they sell both rosin (for electrical) and acid (for plumbing), so don’t buy solder in the plumbing department!
O.k., without my new pen shaped tip, for the time being I am limited to my large screwdriver shaped tip. I tested out your procedure and here are the results. First, it is difficult for me to keep the iron tip tinned on any setting above 3 1/2. The solder just boils down to almost nothing on the tip and has little heat transfer ability. At 3 1/2, I can keep the tip tinned for a little while before I have to clean the tip again and reapply a little solder. The RadioShack tinner/cleaner does a good job of tinning the iron’s tip, but even it loses effectiveness rather quickly after I turn the iron above 3 1/2. FIRST QUESTION: What does a good tinned tip look like? Does the whole tip have to be covered in solder or is it o.k. for a small drop to be on the end to transfer heat?? Next, I tried the method you suggested for soldering to the rail. I turned the iron on 3 1/2. I used a test piece of track, which wasn’t secured so I modified your procedure slightly. I tinned the wire along with the bead of solder on the iron’s tip. Between the two, I have all the solder I need without adding any more. I added rosin flux to the spot on the rail where I was going to install the feeder. I touched the tinned wire to the flux and applied the iron’t tip, specifically the side of the tip where the bead of solder was. I held it on there for 4 seconds. The ties did melt some, but it didn’t look too bad. I tried the same procedure at 3 seconds and still got a couple of somewhat melted ties. I lowered the temperature dial down to 3 (exactly half) and kept the iron on there for 3 seconds. The ties still melted but not very much and less often. I tried using wet cotton balls on both sides of the joint which helped a little, but they did not keep the heat from getting the two ties right below the solder connection. I figured out that if I lightly press the wet cotton ball to the ties directly after moving away the iron, it seems to lessen the melting some. The main thing I have been concerned and worried about, as yo