What are the tools every hands-on projecteer needs? To answer that question, we went right to DIYers themselves, specifically the exhibitors at last fall's World Maker Faire NY event.
One tool everyone agreed on is a Multimeter. It's surprising how much information you can glean from a simple resistance reading or by checking out the voltage drop across a series of LEDs. Basic analog meters start at around US $15, but consider getting one with a digital display and an audible continuity tester. When you're up to your arms inside a chassis probing a pair of contacts, you don't want to keep looking away just to see if you have continuity between two points. You'll also want a variety of ends for the probes, such as alligator clips and PC board lead hooks.
Next you'll want a Soldering Iron. Some of the Maker Faire geeks didn't look for much more than the simple ones that cost less than $10, but others wanted the flexibility that a digitally controlled soldering station brings ($80; more for a name brand such as Weller). With advanced projects, you may need to vary the iron temperature depending on your components.
Sometimes, though, you just need a lot of heat, especially when soldering a large component or a thick wire. A conventional iron can't heat a large mass of metal quickly enough. Casey Haskell of Sparkfun Electronics likes to have a propane-powered pen iron for its portability, while others prefer a high-watt soldering gun.
Some of the Makers have moved beyond "through-hole" PC boards and now like to work with surface-mount devices. The "right" way to reflow solder for SMDs is using a purpose-made oven, but many a brave adventurer has gotten by with a toaster oven and some TLC. You can also use a hot-air gun or a hot-air pencil, which lets you do SMD one component at a time. Justin Huynh, who hacks remote-controlled cars with Arduinos, the popular DIY microcontrollers, uses this technique as well as a variable-temperature Weller. "I've always used the Wellers," he says. "My friends who are engineers use them. They just work really well."
Along with an iron, you'll want to have a way to desolder, for those inevitable missteps. Some people like to use desoldering braid; others like Desoldering Irons with suction bulbs. I've used both, and I find the irons do a better job with less heating of the components.
Most of us start out using batteries or cannibalizing power adapters, but a good bench Power Supply lets you control voltages precisely as well as measure and limit the amperage flowing through the circuit. You can get a reasonable single-voltage supply for $120 or so, such as the 18-volt, 3-ampere supply made by Extech Instruments. More advanced ones will offer multiple controllable voltages, useful when projects have more than one input voltage.
A bench supply goes well with a large Protoboard, one that supports multiple supply voltages and has lots of real estate to lay out chips. If you do a quick proof of concept on a protoboard first, you can save yourself a lot of grief when you try to set out a permanent version (or send it out to a printed-circuit-board fab).