Tool timeOriginally published 2005 in Atomic: Maximum Power Computing Last modified 16-Dec-2014.
Let's go low-tech for a moment.
I'm talking knives and stabbing weapons, people.
Every nerd needs a pocket multi-tool. What if you've got no money to speak of to buy one, though?
A decent Swiss Army knife is fifty US bucks retail (or a lot more, if you choose your retailer poorly). My own favourite, the Mini Champ, is half the price, but it's not what you'd call a heavy-duty tool. A Leatherman Charge'll set you back about $US100.
Well, don't buy some Chinese knock-off. They're invariably cheaply made out of lousy steel. Much better to visit the local pawn shop and/or auction site, buy a used brand-name knife for close to nothing, and clean, oil and sharpen it.
The bottom's dropped out of the used Swiss Army knife market in the USA since the authorities there started selling airport-confiscated pointy things by weight on eBay. Various other dealers sort out and onsell the things again, for all of those moments when you find yourself in need of fifty pounds of plastic-handled scissors. Fortunately, some of those dealers sell the things one at a time, instead of in sacks.
This situation may change in the near future, because the well-thought-out rules (From The Legislature That Brought You This!) which have so successfully protected so many of the world's airlines from assault by legions of Victorinox-armed religious fundamentalists are being relaxed, a move which will apparently soon result in the death of all of the world's flight attendants.
But, in the meantime, it's not too hard to find a Swiss Army knife or brand name multi-tool on eBay for a very reasonable price.
[Note that the Great Swiss Army Bargain Time is over, as of about 2007; the confiscation rules and eBay sales actually do still exist, but far fewer people are carrying their pointy things into airports to be confiscated. So prices have shot up.]
To de-crudlicate a Victorinox, Gerber or Leatherman product that's apparently spent seventeen years in the armpit of a wendigo, you can't go past an ultrasonic cleaner. This isn't much of a Top Tip, since basic ultrasonic cleaners big enough for a pair of Dame Edna glasses have been cheap-ish items at electronics stores for many years, but it's still worth mentioning.
An ultrasonic cleaner lets you get serious dirt off intricate assemblies using nothing but plain water and a bit of dishwashing liquid (or water alone, if you are cleaning a baby). Without the ultrasonic magic, you need to fiddle around with cotton buds and paper towels, and probably also solvents that'll make the plastic scales on the sides of a Swiss Army knife go all gummy.
If there's rust to deal with too, you can just use metal polish. But "rust erasers" work, and you can also get fibreglass pens that scrape off small amounts of rust very effectively. But they also shed bits of their fibres, which will stick in your hands and make you sad; use them with care.
On to the oiling.
First rule: Put the blue and yellow can down.
WD-40 is not one of my favourite things. I've got some, of course; every home really should have a can. It's a great Water Displacer (hence the name), and it's good at stopping squeaks in filthy rusty things, and at helping to loosen bolts, and so on. Though if you try cleaning piano keys with it, you're conducting an ad-hoc experiment in the effects of oily kerosene on the material the keys are made of. If they're ivory, the Maestro's probably going to enjoy slamming the lid on your head a few times.
(It's not much good for the tuning pins, either.)
WD-40 is mainly kerosene, and it is a lousy lubricant. It does the job on squeaky gate hinges, but if you want to clean something smaller than a tractor, oil it, and/or stop it rusting in the future, WD-40 will disappoint you.
What you want is a proper lubricant. Sewing-machine oil from the supermarket is plain light mineral oil and will do in a pinch, as will 3-In-One oil (though the standard, non-"Motor Oil", formulation of that stuff contains vegetable oil that'll gum things up over multiple applications). But for real industrial-strength purposes you want oil that's meant for killin' machines.
The story goes that CLP was created in response to a 1971 US Army "Purchase Description" for a Cleaner, Lubricant and Preservative that was widely believed to be impossible to make - until someone made it, two years later. Today, a significant proportion of the world's firearms smell of this stuff, and for very good reason.
Gun-nuttery is entirely optional. CLP works just as well on tools of all kinds, computer fan bearings, bicycles, those stupid spring-loaded Klingon daggers; you name it. It's well worth what you pay, which shouldn't be much for a small bottle that'll last most people for many years.
On to sharpening.
Making blunt blades - including scissors and screwdrivers - sharp is something every geek should be able to do. You don't need to have a propane forge and a deep affection for old leaf springs to care about this stuff. Even discount-store kitchen knives and $3 used multi-tools deserve a decent edge; a sharp knife really is safer than a blunt one, unless someone's actually trying to kill you with it.
Yes, you can now buy ceramic knives that hold their factory edge for an incredibly long time (after which you have to send them back to the factory for sharpening...), but those blades have zero tolerance for abuse, and a proper geek-knife is often used to pry things open. So steel is still where it's at.
(Oh - patriotic Australians may be proud of the self-sharpening Wiltshire Staysharp knife, but (a) self-sharpeners are for wusses and (b), thanks to the blade profile that stops them being worn away to nothing by their scabbard, Staysharp knives, and most other self-sharpeners, are actually quite lousy at cutting anything but the person trying to use them.)
There are, of course, a million and three gadgets that all claim to make it easy to hold a particular sharpening angle, and some of them even work. The recently developed Columbia River Slide-Sharp is probably the best of them. Every electric sharpener ever made is equal worst.
It's no big deal to learn hand sharpening on a few two-dollar knives, though. Cheap steel probably won't hold an edge for long, but what do you care; it's better if it goes blunt fast, since you want practice at sharpening. There are about a thousand different sharpening techniques, all of which claim to be the best, but all you really need to do it is appropriate abrasives.
This used to mean actual honest-to-goodness natural stones, which wear into a saddle shape with use and then need to be dressed back into flatness, or thrown away. Then came harder artificial stones made from crystalline aluminium oxide (a.k.a. corundum - sapphire, emerald, ruby) or the somewhat-harder-again silicon carbide (which can be had on waterproof sandpaper, which can sharpen blades just fine if you put it on a sheet of plate glass for flatness).
Unlike some natural stones, diamond cards work fine with only water as a cutting fluid (or spit, if you want to look macho). The purpose of the cutting fluid is just to float the metal filings out of the cutting grit, not to lubricate; most diamond cards have holes in the surface to collect the filings. You can use oil with diamond sharpeners if you like, but there's little reason to do so. Most old-style sharpening stones won't work right with water, but on a diamond card oil is just messier.
And, to a first approximation, diamond cards never wear out.
This is because diamond, even very cheap grey industrial diamond, is much harder than everything else in the world, excepting a couple of highly exotic compounds that cost slightly more than happiness. The Mohs Hardness Scale has corundum at 9 and diamond at 10, but the Mohs scale isn't linear, it's "ordinal". It just tells you what's harder than what, not by how much.
If you make a new linear scale that assigns 9 Hardness Points to sapphire, diamond actually scores about thirty-four.
Quartz - which easily scratches even the hardest glass - is 7 on the Mohs scale, but diamond is about 15 times as hard as it.
Super-cheap diamond cards may have a very thin coating and wear out when the nigh-indestructible diamond is mechanically knocked loose from the metal matrix, but even the cheap ones last quite well, in my experience. The only way they go wrong is when the glue holding the plastic backing plate onto the card proper lets go, and the card still works then.
The only thing really wrong with the cheap ones, generally instantly-recognisable three-piece colour-coded sets with long oval holes, like this...
...is that many dealers try to sell them for the same price as top-quality diamond cards.
You can get very nice diamond cards, and files, and paddles, and little sticks, and rods, and various other form-factors, from companies that also make knives, and from a few specialists like Eze-Lap. You can get good-enough diamond cards, however, from many of the same discount stores that sell the suspiciously cheap Chinese kitchen knives on which you can practice sharpening.
Less than ten bucks is the going rate for a set of three differently graded cards. Add another two bucks for an almost-straight butcher's steel (which you use to realign the edge on a knife, not sharpen it), and you're done!