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By Jack Ganssle
Spares & Tools
OK, so we do have a spare VW engine in the basement, though it's in pieces. And yes, there is a leftover transmission there as well. Gentle wife nudges me about the extra boat transmission in the living room. Somehow I just don't see that anymore as it's buried under a couple hundred feet of spare rope.
The office is piled high with currently-unused evaluation boards from vendors galore. I just can't bring myself to toss that old 186-based development system, or the 68HC12 boards used by my University of Maryland students a few years ago. They may, after all, be handy for something someday. The boards, that is. The students are thriving.
And tools! They're everywhere here. My desk's pencil cup has more screwdrivers and X-Acto knifes than pencils. We computer folks like to consider the PC a mind-tool that increases the power and reach of one's brain. Conventional hand tools give us a similar ability to manipulate the mechanical world in ways impossible via the unaided human body.
I'm a fanatic about tools, keeping them clean and sharp, buying only the best, sometimes collecting the cream of the technology of yesteryear that, while out of style, may still be the best solution to a problem. Shipwrecks in 1978 and 1992 devastated my collection but I've rebuilt it each time.
Like many of us I've accumulated a lot of specialty tools, ones used perhaps only once every year or two. Sometimes you can't make a quarter-inch screwdriver do everything. Just try to change a fine-pitch SMT part without the right rework station and an awful lot of skill. Not to mention youthful eyes.
I got to thinking about this when we cleaned the boat out recently, preparing for a summer's jaunt to Bermuda and the Turks & Caicos. Years of accumulated tools and spare parts filled practically every locker. Voyager is only 32 foot long, yet there's something like half a ton of spare parts and tools squirreled away.
What happens if the alternator fails? No problem, there's an extra. Injectors? 4 spares. If a sail rips we have a complete set of sailmaking tools and spare material. Rigging, plumbing, electronics (yes, there's a small scope under the chart table). we're set for most sorts of failures.
My best friend is also an embedded engineer. He takes his 40 footer to the islands with us each year. Willow is equally loaded with tools and parts.
Years ago I chartered a boat in St. Thomas. Reviewing the paperwork the agent muttered "thank God" when he came across my occupation. That puzzled me till he explained that engineers bring the boats back in better condition than when they left!
What is it about us engineers? Too many of us can't write, we're poor communicators, often terrible at relationships. They say an extroverted engineer is one who looks at your shoes when he's speaking to you.
Yet by and large we're masters of the mechanical world. How does a computer work? Well, we know exactly. Engines pose few mysteries. When the neighbor can't figure out how to connect the cable TV, Tivo and DVD player, we're the first he calls.
It's immensely satisfying to understand how stuff works, and to have the tools, parts and competence to maintain and repair most bits of equipment. I like the feeling of being a master of the technology that surrounds us, not its victim.
The irony, of course, is that it's all but impossible to repair most embedded systems. If something electronic in a VCR fails, well, it generally gets tossed in the trash. That annoys me no end, but without schematics and custom ICs repairs are impossible.
Yes, sometimes my kids aren't too thrilled when they have to move fifty pounds of fasteners to get to the duct tape. But two years ago we were in mid-ocean when the wind deserted us for four days. We motored, and motored, and motored. Then a high pressure injection line blew apart, something that absolutely never happens to modern diesel engines.
We had a complete set of spares aboard. 2 hours later we were under way again. I haven't heard a complaint about the tools and spare parts since.