I’m getting ready to solder the necessary wires to a Soundtrax decoder. I’ve heard too many horror stories about these guys being hyper-sensitive to dirty track, so even if this is supposed to be a plugNplay, I want to eliminate this potential weak point.
There doesn’t appear to be much room for placing a heat sink. Is it critically important for me to use one of those? And if that’s the case, can you offer some pointers?
T-I-A …
A heat sink is not required, but a controlled temperature soldering tool or low wattage soldering iron with a very small tip, and rosin core electronics solder is required. Apply heat only long enough to melt the solder.
I have never used a heat sink for soldering. Never. Heat sinks are umm how does one say this nicely, a crutch for improper soldering practice. Heat the board and the wire simultaniously and quckly. Hit the joint with the solder. Remove the heat and then blow to cool, the rest of the components won’t even know a solder was done.
But, how is soldering going to reduce the sensitivity to dirty track? The two aren’t related. Just use the cute little plastic connector caps designed for the unit. I have never had trouble with those unless they were put on wrong.
Just make sure your soldering pen (the gun-type are overkill) is hot, clean and tinned and your wires are tinned. Instert the wire into the hole and heat the pad (not the joint).
I solder alot (custom DCC installer and brass loco fixer-upper) and i prefer to use a Weller 30-25 Watt BLUE handle soldering pen.
Hope this helps.
David
Thanx a lot for the replies, guys! I guess the thing I need to do is get a precision iron, something smaller than my 80-watt tool.
Those end tabs are a piece of cake to solder. However, be very careful with those two little holes where the speaker wires go, and don’t let any solder overlap the edge of the holes, and short out to some other connection nearby. Check both sides of the decoder, to see what is there, before soldering the speaker connections. There are some components very close to the speaker holes on one side of the decoder.
I have a 15 watt iron I use for soldering decoders and associated wiring - PLENTY big. Solding wires to the tabs there for the track pickups, motor, and lights is pretty easy. Strip the wire, twist the ends (since the wire is usually stranded - don;t want stray strands that could short somewhere sticking out, and apply some solder to the wire (called tinning). Stick the wire through the hole in the proper pad, pinch it over so it’s physically snug, apply heat and solder. It should take only a second to heat and melt the solder. Do NOT apply the solder to the iron.
–Randy
Actually, all soldering books and guides and everyone that I know that solders acutally add some solder to the iron. The reason is that the solder on the iron acts as a heat conductor. Without it, you will run the chance of heating up the surrounding area. Solder on the tip (called tinning the tip) will allow for the most efficient heat transfer to the joint.
Clean the tip between uses (the tip will oxidate in about 20 seconds…hence becoming a poor heat conductor)
Try not to apply the iron (heat) directly to the joint, but rather just off to the side of it.
David
[#ditto] You have to tin the soldering iron for good (fast) transmission of the heat… David is right on.
Brian
Yes you should tin the soldering iron tip but you don’t have to do this ever time you heat up the iron, and when soldering the joint you NEVER apply the solder to the iron, you use the iron to heat the joint anda pply the solder to the joint.
–Randy
[:-^]
What kind of Iron are you using? I use a professional pensil type and you have to tin the tip about every 20 seconds…aparently the laws of physicis work differently in your part of the world.
David
Sounds like the iron needs a new tip. One should not have to do this.
Nope…tis a new tip. How long do you go without cleaning the tip? (keep in mind the tip I use is a very, very fine one intended for micro-soldering)…some custom decoder install I do for customers require that I forgo the 9jst connector, open up the female end to it and solder wires directly to it (for example…a Tsunami in a 3 truck shay…everything fits in the tender, unlike the crappy soundtraxx-intended installation). It requires uber-percision and a very hot and freshly tinned iron. There is no room for error.
David
Do you clean it? I wipe the tip on a wet sponge after every soldered conenction. If the tip no longer stays shiny after cleaning it’s time to replace it. Any sort of abrasive will quickly remove the plating ont he tip and it will NEVER stay clean. Using the tip to strip the insualtion off the decoder wires, or touching it to heat shrink tubing while shrinking it, will also contaminate the tip and make it not transfer heat properly.
–Randy
There are actually several possible ways to get the job done (I’m waiting for the guy that only uses a 250 to 340 watt electric gun and says that anyone who doesn’t do it his way with several heat sinks in line is a nut case…). While I most often agree with everything Randy says, this time my own experience and training prefers David’s way of doing it ( notice I said “prefers”). I always use a small drop of solder on the iron and place the iron at the joint. The solder will flow to the joint immediately. Get out right then. The whole thing will be done in about a second. Don’t wiggle the wire to see if it has set! That is what usually causes the “Cold Soldering Joint”. Not a good thing. Get in, make the solder, and get out. Let it cool. This is actually a very easy task.
I’ll respectfully and politely disagree. It is important to get the pad and the wire hot. A drop of solder on the iron may flow onto the wire, but you’re not going to know that you get the pad hot enough to get a good bond. That’s the reason to heat the surface, and then let the solder flow to it. The drop method probably works most of the time, but I don’t hink it is the most reliable method. With a properly small, tinned iron, small enough solder, and clean surfaces, it isn’t goign to take long, and nothing is going to get too hot.
You are using the “textbook” method of electrical soldering. Yes it works very well and there is absolutely nothing wrong with it. BTW about half the time, depending on the size of the joint and what is needed to do a good job, I also add a very small amount of solder to the joint as soon as the solder flows. If the solder flows to the pad (That is actually where I place the iron, as close to the wire as possible) it is hot enough. The reason I use a small drop of solder on a well tinned iron is to increase the surface area of the heat transfer. This way the area to be soldered heats much faster and does not have time to spread the heat to things you don’t want melted. Often the joint does not need any more solder. Many people use way too much solder which can cause problems as well.
I originally learned to do electrical soldering while working as a summer hire at at phone company. Part of my time was spent soldering wires to a mainframe (back in the late 60’s). There we used 120 watt monster irons to do the job. You wrapped the 22 or 24 guage wire around a post hit the backside of the job with the almost red hot iron, touched a bit of solder to the other side and things melted quickly. You didn’t want to touch anything nearby for a minute or so… After I opened a recor
What I like to do is
tin the connecting wire first. (Melt solder on the wire…this makes it stiff)
Stick the wire through the hole on the solder pad
Heat the wire (not the pad) with 15->30 watt solder pencil tip gun.
The tin on the solder will melt and downward and fill the solder pad hole making a secure connection.
Easy as pie.
15 installations and counting…
If the decoder doesn’t have holes then apply solder resin using a small brush. Then apply steps 3->4 above.