I carry (by choice) a pretty specific (and now discontinued) Kershaw pocketknife, their 1820 "Needs Work." I own a pair of them, or I did, and I work them pretty hard; it's my knife-of-all-work, opening boxes, trimming sections of the Velcro™* strip we use instead of tie-wraps or -- shudder -- cable-lacing, pencil-sharpening, trimming, marking, etc. etc.
Went to put my knife back into my pocket yesterday and the clip wouldn't catch. It spun around, having somehow lost one of the tiny screws that hold it to one of the scales. Frustrating, but I figured I'd rob a screw from my backup knife, which is presently needing a new spring anyway (in my hands, the springs last an average of three years. YMMV). Kershaw is good about parts support but I usually wait until I need a couple of items in order to not burn up twenty dollars of their time over a single five-cent part.
I can't find my backup Kershaw 1820. There's a chance Huck the cat has taken it, since it normally lives on my dressing table and he has been known to remove items when trying to wake me in the morning. If so, it can't have gone far, it's too heavy. There's a chance it's buried in the far back corner, under spare socks and a folded blanket and I'll be looking into that this morning. (In the meantime, I found a third one on eBay. Hey, it's discontinued and I like that model; might as well stock up when I find them at a decent price.)
It's surprisingly unsettling. One of those knives has gone into my right-hand jeans (or skirt -- I won't buy 'em without pockets) pocket every morning for years.
* For signal/low-voltage wiring, we use the name-brand stuff, which lasts 10X longer than the generic versions made by electrical-parts makers, is priced slightly less, and is readily available in black, white and screamin' Hunter Orange.
2 months ago