How to make stuff that doesn’t fall apart.
Posted by Rob Cruickshank on May 16th, 2008
While installing my latest piece, I was thinking that I should make a list of little lessons I’ve learned over the years about making things so that they don’t fall apart or break down. Sort of like one of those folksy little overpriced books of wisdom, but actually useful. So, the beginning of an open-ended list. Feel free to add on in the comments.
1) Learn to solder properly. Seriously. It’s not hard.
2) If you are going to make more than one copy of a circuit, make a circuit board. The time spent designing the board will be saved in construction time and troubleshooting. Hand-wired boards always have errors. Circuit boards often have errors, but at least it’s always the same error.
3) Breadboards are for prototyping. Your final circuit should be soldered or wirewrapped.
4) Use cable ties. Don’t have nests of dangling wire. Or, if you really want to impress, learn to lace cable harnesses. Make sure you cut cable ties properly- don’t leave razor-sharp ends.
5) Colour-code your wires. Sure, it’s easier to buy one big roll of a single colour, but you’re going to hate yourself when trouble-shooting time comes.
6) Learn to wire connectors with the all the conductors the same length. If you yank on the connector, all the wires should share the force, not just the shortest one.
7) Use heat shrink to insulate connections, and also to providemechanical strain relief for connections. Get a heat gun. (A paint-stripping gun works well, a hair dryer does not. In a pinch, you can use the side of the soldering iron, up from the tip, but the results will be ugly.
8) Drilling sheet stock, such as project boxes, with ordinary twist drills is asking for trouble. Use a step bit, and you will get a nice round hole, and the piece won’t grab the drill bit and whirl around like some ninja weapon. Use a centre punch to make an indent whenever you’re drilling, the spring-loaded ones are especially handy. Always drill a pilot hole first, then the bigger hole.
9) Use lock washers. Or nylon locking nuts. Or Loctite. Or even nail polish. Just don’t let screws and nuts loosen.
10) Use separate power supplies for digital stuff like microcontrollers, and electromechanical stuff like relays and motors. Make sure your power supply is rated for the amount of current you circuit draws, and is the correct voltage. Don’t trust the label. Measure.
