The Compressed Air Keyboard Repair
My favorite keyboard (probably of all time - the only ones that come close are the 'boards in my WallStreet and Pismo G3 PowerBooks and my PowerBook 1400) is the Kensington SlimType (currently US$35.95 at Amazon.com), which I love dearly.
It's definitely the most comfortable and non-fatiguing freestanding computer keyboard I've ever used - but it gave me a scare recently when the F and W keys stopped responding properly. A keystroke would register only when the key was pressed more firmly than usual, and the subtle over-center click of the SlimType's scissors keyswitch mechanism was missing, with the malfunctioning keys feeling "numb" and offering higher than normal resistance.
My initial approach was to attempt taking the keyboard apart to see if I could identify what was ailing it, but after removing all of the screws I could find on its bottom panel (many) and prying open the plastic clips around the case periphery, the keyboard still stubbornly refused to separate. I was reluctant to apply more pressure, as the plastic already seemed stressed by my efforts to the point of near-damage.
Time for plan B, if I could come up with one.
Upon reflection, I figured that the most likely reason for the key malfunction was debris fouling the scissors keyswitch mechanism - which partially opening the case had seemed to verify visually. There seemed to be a fair bit of dust and crud in there. The marquee feature of the SlimType 'board is its excellent, laptop keyboard type scissors keyswitch action - very short, low-effort travel and smooth but positive feedback. Because of the short travel, it wouldn't take much foreign matter in the wrong place to affect the key function.
This particular 'board has had about three years of intensive production use (indeed, the letters on some of the most frequently actuated keys, like the e, are beginning to wear off from use), and I had never previously made any serious attempt to clean below the keys, which, as I had now discovered, was not that easy to do by conventional, take-apart means.
Since I couldn't get the keyboard to come apart, at least without apprehended serious risk of breaking something, I decided to try giving it a shot of compressed air to hopefully dislodge whatever was messing up the key action.
I started up my old Campbell-Hausfeld air compressor in the garage, which is usually used for automotive related tasks like inflating tires and powering an air-chisel, but a blower nozzle and a 100 PSI blast of air proved the charm for my keyboard, causing a cloud of dust and debris to emerge from the aperture below the keycaps. Whatever had been causing trouble literally got blown away, and the keyboard was working perfectly again and has continued to do so.
For folks (presumably many reading this column) without convenient access to an air compressor, one of those little aerosol cans of compressed air used for cleaning photo equipment might do the trick.
Charles Moore has been a freelance journalist since 1987 and began writing for Mac websites in May 1998. His The Road Warrior column was a regular feature on MacOpinion, he is news editor at Applelinks.com and a columnist at MacPrices.net. If you find his articles helpful, please consider making a donation to his tip jar.
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