Good introduction to soldering kit?

[David]

I want to start soldering, specifically decoder installs. I am looking for some kind of "learn soldering" kit, preferably geared toward the small/light/fragile type of soldering I will be doing - I want to get some structured hands on experience before doing a real install. A kit that comes with a soldering iron and the appropriate solder would be best. Budget wise I'd prefer under $25 shipped, but am open to advice.

I've found 2 examples, I'm not sure how relevent they are.

http://www.pololu.com/catalog/product/321
http://www.hobbyengineering.com/H2102.html

The first one seems better, as it contains everything needed to get started. A quick glance through the booklet (a PDF copy is on the website under reference) seems to show that the kit provides a gentle learning curve with several activities to help a first timer learn the skills before even making the first attachment.

My one question is whether cheaper soldering irons (like the one included above) are "worthless" for doing decoder installs. If I want to do expert work later I am always open to upgrading to a better tool (tool investments are the one type of spending I don't question later on), I just don't know if acceptable results can be obtained with a basic tool. Are there soldering irons that would be significantly easier to use for a beginner (fewer mistakes)?

[KenS]

I'm a long way from being a soldering expert, but I think you have the right idea in getting a kit to practice your skills with.  And a kit with instructions that assume the builder is a complete novice should get you started (you can find instructions on how to solder online as well).

The first kit looks better, as it includes the solder and iron, although you can get both cheaply at Radio Shack. However it uses lead-free solder, which needs more heat to melt, so it's a bit harder to use.  Safer perhaps, but as long as you wash your hands after soldering, and don't eat while doing it, there's not much risk from lead solder (lead vaporizes at a higher temperature than normal soldering uses, so the fumes don't contain lead either way, it's skin contact and in particular ingestion that's the problem).

It is a good idea to avoid breathing the fumes though. The combustion byproducts of burning rosin (the flux inside the solder) are similar to those of cigarette smoke, and long-term exposure can reportedly cause asthma. Ventilation, or at least a small fan, is a good idea.

The two things that kit doesn't appear to include are a sponge for cleaning the iron tip (an ordinary small sponge places on a small plate and moistened works fine) and a coil of de-soldering braid, which is an important tool to learn to use.

[Martijn Meerts]

I've never been happy with the cheap soldering irons (and I've had quite a few =)), they tend to be more annoying than useful really ...

[inobu]

David,

What you don't want is a $14 soldering iron screwing up a $30 decoder.

The soldering iron is used to transfer heat although many of us think it is used to transfer solder. 

Soldering is a technique that involves heat, time and flux. What you are doing is heating up the metallic pad to a point that the solder will melt upon contact. In the respect to time, you only want the pad or contact point to heat up for no more that a few seconds, the flux helps in cleaning and solder transfer.

The problem that we run into is the iron size and tip size. You have to match everything, if the tip is too small it will take longer to transfer heat to the pad. if the tip is too big it will transfer too much heat that will fry the components. The soldering irons are like screwdrivers the size needs to match.

I would spend the extra money and get a good iron. It's something that you will continue to use.

To practice for decoding all you need is a tray of pin needles and small gauge wire. solder the wire to the pin head in a second and you will be good to go.


This is the best tutorial

<a href="http://www.youtube.com/v/I_NU2ruzyc4" target="_blank">http://www.youtube.com/v/I_NU2ruzyc4</a>


Inobu 

 


   

[David]

The problem that we run into is the iron size and tip size. You have to match everything, if the tip is too small it will take longer to transfer heat to the pad. if the tip is too big it will transfer too much heat that will fry the components. The soldering irons are like screwdrivers the size needs to match.

I would spend the extra money and get a good iron. It's something that you will continue to use.

So if the tip can't be too big or too small for the task at hand (soldering N scale decoders), what would be an example of a soldering iron that is the "right" size?

[Martijn Meerts]

Depends a bit on the decoder. The really small ones have rather tiny soldering pads, which means you need a really small tip. The bigger ones tend to have soldering pads that are about twice the size, which means your tip can be twice the size.

Personally, I have a chisel tip (one of those that look like a flathead screwdriver) of about 1-1.5 mm. I also have a digital soldering station where I can set the heat precisely, because too much heat can easily burn the components closest to the soldering pads. (I tend to solder at around 300, never touching the soldering pad longer than 2-3 seconds.

[CaptOblivious]

I used a Radioshack  firestarter for a couple of years before trading up. I had the 25W model; it had a largish tip, and got pretty hot if you left it plugged in too long, but it was cheap, and parts were ready at hand (I had a tendency to destroy the tips, and new ones were cheap).

There's absolutely nothing wrong with soldering your decoders with a cheapo iron. I taught myself SMD soldering (including some very finely-pitched ICs) using my Radioshack POS, and the largish tip was hardly an issue at all. I certainly never fried anything from a too-hot iron, either.

So, all that said, I strongly recommend getting a cheapo iron to start out with, and some fun basic kits (the ones you linked to looked fine, but if you've got a Radioshack nearby, get your iron there so you can get parts easily). Have a look around the Sparkfun website for some fun kits too:
http://www.sparkfun.com/commerce/categories.php?c=157
http://www.sparkfun.com/commerce/product_info.php?products_id=9883

Once you get the hang of things, start wiring in decoders that have a good warranty that covers mistakes (e.g. TCS, Digitrax, Lenz), and you'll pick it up really quickly.

THEN, once you've got the hang of it, shell out for a nice iron. Because only then will you appreciate what makes a nice iron a nice iron. Spending money on a fancy iron right now would be money thrown away, I believe.

But that's just my opinion :D

[Martijn Meerts]

Cap has a point. I'd never have thought my soldering station was worth what I paid for it if I hadn't had any experience form the cheap soldering irons.

I would recommend checking out a couple of irons before buying anything though. I've had irons that were so big, they were hard to get a good grip on, and I've had irons where the power cable was so stiff it was near impossible to solder anything at all =)