With this instructable, I am going to show you how to make your very own soldering iron! This entire iron can be built for less than fifteen dollars. There is no catch, and this is just as good at soldering as almost any other inexpensive iron on the market. This iron has a maximum temperature of 1050° Fahrenheit and is equivalent to a 15 watt iron. It works the same way as many other battery powered irons (like this one), but doesn't cost nearly as much.
This is also battery powered so it is portable and you can use it when there is no outlet available. I'm eventually going to put a relay in mine so it automatically turns off the battery pack, when I plug in the adapter. But for now, I'm just going to show you how to build a functional soldering iron that just works. This is not to difficult of a project so i'm sure you can get it done.
If you are going to build this you will already need to have a soldering iron so you can solder the battery holder, switches, etc. If you do not have one you could probably twist the wires together and put electrical tape around them, but I don't know how well that will work.
Disclaimer: Soldering irons can be dangerous if not used properly, do not let the hot tip touch yourself anything flammable. You can easily burn yourself or start a fire if used improperly. I am not responsible for any damage or injuries that occur.
Now that we got that out of the way, let's head on over to the next step to show you what part's you'll need.
Step 1: Materials
All of the part's needed can be found at RadioShack and shouldn't cost any more than 15 dollars.
1. This soldering iron tip (This is what actually heats up to melt the solder. No other tips can be used besides this one, unless you are certain that it has a built in heating element.)
2. A 6 volt battery holder. This one has a built in switch so you don't need to buy one of those, but it is also big. Remember this is what you will be holding on to when you solder. I prefer to use a battery pack like this one, which is more comfortable to hold on to, but you will need to buy a separate switch. If you are buying the second one I told you about then you will also need to buy a battery clip to attach to the battery.
3. A switch (Only if your battery pack does not include one). This is a good one if you want your iron to stay on until you turn off the switch. If you don't want the iron to be on unless you are holding down a button then go with something like this.
4. Anything to mount it in. You can use a project box if you are crafty, or just a block of wood as long as the tip doesn't touch it. I used an Altoids tin.
5. An E-10 lamp base. You can use any kind as long as it has a way to be mounted and electrically wired.
6. A soldering iron to assemble the project. If you don't have one, then you can try tying the wires together or borrow someone else's.
7. Solder for assembling and use of the iron you are building.
Step 2: Prepare to Build
Before you start building, you should probably lay out a design for you're iron. The one that I am using to show you is just a quick one that I made for the sake of this Instructable. I am currently planning a nicer one but I wanted to do this Instructable before someone else takes my ideas. I put a diagram on here to give you a basic layout on how to assemble the iron. This iron draws up to 1.7 amps so don't use any components that can't handle that. Most can though, so don't worry about it to much. I could have put a schematic on here, but since this is supposed to be an instructable that most people can understand. Try to collect all the materials that you need and see if you can find a nice enclosure for it. As you can see, I modified, and mounted components on that. What I will eventually do is to use a fancy necklace box and mount everything in there. That make it fancy, portable, and easy to change the batteries. You just flip open the cover. I'll post a picture of my started project with this enclosure. Also, if you want to make this a plug in iron, you will need to replace the battery pack with a 6 volt 1.5-2.0 amp D.C wall wart.
Step 3: Start Assembly.
If you know anything about electronics, you can do what I am going to do and modify this circuit to suit your needs. If not, don't worry, just follow the diagram that I posted. It is the simplest possible way to get this working. If you have any questions, just ask. You can post a comment or e-mail me at firstname.lastname@example.org.
Step 4: Troubleshooting
If you're iron doesn't work, don't worry, that's what i'm here for. There are many things that can go wrong with your iron. I'll post the most common ones below.
1. "Iron doesn't get hot but is slightly warm." You might be using the wrong kind of batteries. The only batteries that you should use are rechargeable NiMH, alkaline, or lithium (haven't tested). I highly recommend the rechargeable NiMH even if you don't have some. Go buy some. They should be rated at 1500-2000 mAH. Don't worry, most are. This iron (as all battery powered irons) will suck up batteries, so make sure that you can recharge them. Also consider using a wall transformer.
2. "Iron isn't hot at all." Still try replacing the batteries incase that is the problem. Try to touch the leads of the batteries to the tip directly so you can see if it get's hot. If it does then it is either a bad wiring connection, you wired your switch wrong (If your switch has 3 connections, then wire the ones that are closer together, not the ones that are on opposite sides), or you burned out your tip. Burning out the tip is unlikely unless you cracked the heating element with too much pressure or gave it to much voltage.
3. "Batteries get hot, but tip doesn't" You are shorting out your batteries. Take them out immediately to avoid any chemical leaks, explosion, or fire. Try to find the connection from the battery holder that is shorted out. The two leads from the battery holder can never touch. Put tape or heat shrink over your connections.
If I didn't get your question, just ask it in the comments section below. Im always checking my inbox.