In this Instructable, I've put together a list of tips and tricks I wish I knew when I was first starting out. Each "step" is a different category, and each numbered item is a tip or trick. The bolded heading in each item is a condensed version of the few sentences that follow.
There is a list at the end of my favorites/the most important ones. If you read nothing else, I'd say go to the end to get a few good ones and also to get the best tip ever!
Step 1: Designing
- Look for and use designs already built by someone. It is inefficient to design something from the ground up if it has already been designed by someone else. However, you must be sure you are not violating any copyright terms.
- Design on paper. The power of technology often slows us down, as we have to constantly save, worry about crashing, save, skip that song, and then save again. If you start on paper, you can get most of the basics done without the hassle of technology.
Step 2: Prototyping
- Prototype to perfection. Don't stop prototyping until you have the design working as it should. Don't say, "I'll include it in the final design." Always fix all problems in the prototyping stage before moving on.
- Color code wires. Using colored jumper wires when breadboarding lets you keep track of signal and power lines easier. I usually use the standard red for positive and black for negative, with the other colors representing signals.
- Use short wires. The long jumper wires are messy (and are a pain to work with), so by using shorter wires, you can clean up the breadboard. Also, the shorter the wire, the less interference you'll get.
- Use the real parts. This kinda goes along with number one, but use the real parts in prototyping. Don't use a lesser resistance resistor in prototyping, only to switch it with one in the final design. Make sure the design works with the parts you will use.
- Don't bend the leads. On a DIP IC chip, it is all too easy to bend the leads when putting it into a breadboard. Once they are bent, you will have a tough time straightening them, and they'll be much weaker. Just be gentle, and don't force it.
- Use a benchtop power supply. I don't have one (I'm in the process of making one), but if you do, you should use it as you can monitor current flow and control the voltage easily. Also, they often have short circuit protection, which is a plus for prototypes.
Step 3: Troubleshooting
- Troubleshoot core elements first. When you first start trying to fix a circuit, you should always start with the core elements. They are most likely to fail, and, as they are at the core of things, one issue can take out the whole system. By starting with the main parts, you can eliminate many possibilities.
- Start with the fastest things. It is smart to check the things that are easy and fast to check first. For example, if you check power before all the other connections, you can eliminate that option faster than the other way around. When I troubleshoot, I use this list:
- Check power. Most commonly, I've got power hooked up in the wrong place or I've blown a fuse.
- Check connections. The biggest problem besides power is that I've hooked something up wrong. Check all of your connections, however sure you are. The worst is when you have an LED backward and you spend three hours on every other connection except that one.
- Check parts. Sometimes parts come damaged (or, more likely, I've damaged them). A ruined IC or capacitor could very well be the culprit.
- At this point, I usually end up resorting to praying and Stack Overflow (it isn't very often I get this far down on the list though).
- Use good tools. Often hobbyists make do with what they have, but when troubleshooting, that can cause problems. Get a decent multimeter that you can trust and will give you accurate readings. Another tool is an oscilloscope. I don't have one, so I can't preach too much about them, but I have used one and they are lifesavers. In a nutshell, an oscilloscope is a voltmeter that will graph the change in voltage over time. They are especially helpful in a project where an oscillating signal is needed.
Step 4: (De)Soldering
- Clean the tip. Soldering requires the tip to be very hot, and high temperatures speeds up the oxidation process which will ruin your tip faster. By cleaning your tip, you can preserve the life of the tip. A dull, rough looking tip needs to be cleaned. A shiny, smooth one is just right. A damp sponge cleans hot irons really well.
- Use the right tip. When soldering, a lot of beginners think you want the small pointy tip to solder the small stuff. While in some cases it is nice to have a small tip, often I use a flat chisel-like tip. In this way, I can transfer a lot of heat really fast, solder the joint, and pull away. You want to spend the least amount of time with the iron on the part. In the image of the tips above, the one on the far right is the one I use most.
- Go fast. Many components are heat sensitive, so you need to go fast when soldering. If you don't get it right the first time, let it cool before going at it again.
- Use the right kind of solder. There are tons of different kinds of solder, but the most common is 60/40 rosin core (60% tin, 40% lead, hollow core with a rosin flux). This combination has a low melting point, good conductivity, and is easy to use. The downside is it has lead, which is harmful. It's okay to solder with, just try really hard not to eat it as tempting as that sounds (washing your hands is a good idea too). You can get lead free solder, but it is harder to work with and more expensive.
- Add solder to desolder. Sometimes old parts have crusty, old solder on them, which can be hard to desolder. If you add a bit of new solder, you "update" the old solder, making it easier to suck up. By adding solder, it also introduces some new flux which makes everything flow nice and easy.
- Add a blob to your tip. The flat edge of the tip is nice and wide and can conduct heat quickly, however, when the flat edge is placed against something like a round wire, only a small point is touching. If you add a blob of solder to the tip, the solder will surround the wire, giving more surface contact.
Step 5: SMD Components
- Cut solder. Almost every time I solder SMD components I use way too much solder. If you cut off a small bit of solder (about 1/16") and place it on the joint, you really can't mess up.
- Get good tweezers. For a long time I used those cheap tweezers that come with the soldering iron. Only recently did I get a good pair, and they are life-changing. They are heavy duty and comfortable to hold, and have hardened tips that don't bend.
- Use a larger size. I have soldered size 0402 before, but they are tiny! I moved up to 0603, which are still really small, but manageable. If possible, I would go with 0804 or bigger, as they are much easier to solder. The components in the image above are, largest to smallest, 1206, 0603, and 0402. They are placed next to a dime for size comparison, which shows just how small SMD components can get!
- Solder one side first. To solder a component, I first tin one pad, place the part on top of the pad, and melt the solder. Then add the solder to the other side and clean up both joints. By attaching the one side first, you have a lot more flexibility to make it look nice.
Step 6: Overall Tips
Some of these tips are repeats of what I put in each section, but I thought I'd compile my favorites (and the ones that I forget most often).
- Simplicity! The best tip I know is to simplify! If you don't need that status LED, don't use it! If you don't need that connector, don't use it! Do the bare minimum while making a nice product. You can thank me later.
- Prototype to perfection. Don't move on from prototyping until you are done!
- Troubleshoot fastest things first. Don't spend a ton of time checking other things only to find out the problem was super simple and easy to check.
- Clean the tip. It makes soldering much easier and prolongs the life of your tip.
That's all I've got! Thanks for reading, and, if you have some tips you'd like to share, I'd love to include them!