Back in the late '90s, there was this customer at the gun store where I worked who I thought was super cool. Not just because he carried an HK P7M13—which is pretty cool right there—but because he carried this expensive pocket knife from some brand I didn't know and he could open that thing like a ninja. He'd just reach for his pocket and... BAM! He's got an open knife in his hand. I'd played with various autos and assisted-openers, and I knew how to pop a folder open with a quick wrist flick or twirl a Bali-Song, but the only way I'd seen people have a blade in their hand that fast was with knives in a sheath and no unfolding involved. Because I didn't want to seem like a total n00b, I never asked him how he did it.
Fast forward a couple years to when I bought my first Emerson Commander. Well, duh. I discovered the customer did not use some kind of exotic knife-fu—the little hook on the spine of the blade (the "Wave" in Emerson parlance) just pivoted the blade open by snagging the corner of one's trouser pocket as the knife was produced. I carried that Emerson off and on for years as a general utility knife, but it had a couple of weaknesses. First, it was quite expensive, so losing it was a constant worry. Second, its edge was single-ground in such a way to discourage it from being used for some common daily chores. I get that the Commander is supposed be all tactical and everything, but I do a lot more apple peeling and letter opening than I do sentry eliminating.
Some years back, Spyderco licensed Emerson's Wave opener and introduced it on versions of its popular Delica and Endura. With a conventional saber grind and pocket-friendly dimensions, combined with a reasonable Spyderco price tag, these knives have become popular mainstays in the company's catalog. I've been carrying a Delica for a while and recently added an Endura with the Wave to my collection.
One thing I've been meaning to do is seek some training in handgun retention, and I am given to understand that the fast-to-deploy waved Spydercos are excellent for this purpose (in addition to my usual use for them, which is to tactically and one-handedly "slit film over entree, remove film over beans and rice" in TV dinner preparation). Obviously, for this purpose a training knife would be a good thing to have, but Spyderco only produced blunt training versions of its "Waved" knives for a brief time, and used ones command insane prices on Internet knife sites these days. What to do?
A bit of research turned up the answer, which was "Do what Spyderco fans did before Spyderco licensed the Emerson Wave: Get a zip-tie, cinch it down through the 'Spyderhole,' and voila! An improvised Wave!" This makeshift rig has held up to a reasonable amount of practice thus far, and seems to work pretty much just like the Wave. While it doesn't have much play in it, it has some. Being a separate piece, I'll probably find a way to make it fall off or break eventually. But, hey, zip ties are cheap, and until I luck into a factory trainer for less than the gross national product of Tuvalu, I think my improvised solution will work just fine.