I Ate'nt Dead.
Here's the UPKnife UPD-D4, the "Eclipse Ring2," which is a entry in their lengthy and baffling spread of near identical almost-knives from their (D)efense series. It is, verily, weird.
This D4 variant is the most knifelike thing in their lineup, so that's what I got. This version is steel through-and-through, 440A on the blade and an unknown alloy for the handle. Every other part is steel of some description, too, by way of a magnet readily sticking to all of them.
Made of steel? That sounds like a stupid thing to say about a knife, doesn't it?
Well, that's because all those extra words and letters on the model name designate what this is and what it's made out of. You can get these in a dizzying array of materials, shapes, and construction types depending on what you plan to do with it and how much you want to spend.
Half of UPKnife's D-Series is their "Pocket Sai," which is exactly what it sounds like. You can get this and indeed those in polymer, titanium, aluminum, steel, and various combinations thereof. Most of them are unsharpened, save for the steel versions where you're offered the choice, but you can also get them with carbide steel cutting tips just at the point. UPKnife obviously expect most of these to be real-deal self defense martial arts weapony things, which I suppose is interesting, but I have to say I haven't found myself beset by rogue samurai, cutlass wielding pirates, or any other swordsmen in years, personally, so stuff like that is probably of limited utility for me.
So I got this one, which encompasses: A ring on the end, full length, made entirely of steel, a perfunctory crossguard rather than sai prongs, and fully edged. In the sliver finish, not black. 'Cuz it's shiny, duh.
Actually, more on the "fully edged" in a moment.
The UPK-D4 is a slider opener, if you hadn't figured that out based on the picture of it partially deployed above. UPKnife call it "self sheathing," and when it's at rest the blade sits flat against the handle with a generous 3/16" or so all the way around the perimeter to keep it from acting like a parmesan cheese shaver against your fingers. To deploy it, you press the wide oval shaped button on it to unlock it, and...
...It extends with a snap of the wrist into this 12-3/8" long dagger with a snick that would even make James Howlett flinch. The blade is every bit of 0.185" thick at the root, double edged, and every little thing about the UPK-D4 broadcasts to the world that it is absolutely not fucking around. The whole thing not including the clip is 0.425" thick.
There are a few shorter compact versions of these, but this isn't one of them. I went with the whole enchilada, because why the fuck not? Even when closed it's a full 8" long. It's 183.5 grams or 6.48 ounces, and I would not be surprised if anyone told me my steel version is the heaviest of the bunch. All those polymer and titanium and whatever-else jobbies have got to be lighter than this.
There is a clip on the back side and be still my heart, but it's even a deep carry one. Even so the ring sticks up above the hem of your pocket, I suppose providing an easy draw while it's at it. And you need very deep pockets to trouser this.
It is still, however, possible. All of the edges on it except for the one on the blade are it are chamfered and rounded over, so it is snag free and actually draws quite cleanly and easily. There are some gripping greebles on the handle and it's got a nice bead blasted satin finish all over.
The ring on the back is very generously sized and anyone should be able to fit a thumb through it. Its presence and proportions ought to bring a smile to the face of any ninja anywhere. There's a little glass breaker point on the very tail end of it which is probably superfluous; I'll bet if you whacked a piece of glass with just about any part of this knife you'd break it easily. The glass, that is. Not the knife.
The UPD-D4's mechanism, and indeed everything else in its series, consists of this sliding track arrangement. When you press the button it pushes the head of this locking lug up and out of the pockets on either end of the track, allowing the blade to slide freely until it hits the other end.
From here the blade goes snicker-snack into your choice of overhand...
...Or underhand grip positions.
The blade's kept straight at all times by not only the locking lug, but also these two beefy screws that act as guide pins. Overtravel is prevented by both the lug and the guide pins, and the blade hits home on both of these simultaneously at both ends of its travel.
You might think at first blush this setup is both suspect and a little flimsy. Everyone else probably thinks you will, too, because the internet is just rife with videos of people bashing, prying, twisting, and jumping on these to try to get the mechanism to break. Especially with this all steel version, suffice it to say that this seems extremely unlikely. The bolts are all seriously skookum for what you'd normally find on a knife. The heads on them are no mere T6, T8, or even T15. They're T20, all of them, and the shanks on them terminate in an M4 thread. Even a dinky class 4.8 M4 bolt has a minimum tensile strength rating of something like 840 pounds-force, and you'd probably bend the blade before you got to that point.
And UPKnife have this to say about the alloy:
Optimized for throwing and melee impact, made in 440A high carbon martensitic stainless steel with a hardness of HRC: 45 makes a tough resilient stainless. It can take extreme abuse and offer a point of bending where harder alloys will break, making this ideal for throwing when the worst abuse takes place.
Optimized for throwing, huh? Well, don't mind if I do.
The point of balance is somehow precisely in the middle of this, too, aligned right where the button is.
And yes, 45 HRC is ridiculously soft for blade steel, even for 440A. For optimum edge retention you'd expect it to be at 55 or so. The UPK-D4 is more like a leaf spring than a knife in that regard, and in light of that you'd expect its edge retention to be pretty poor.
And it probably is. And that's probably why its edge angle is what it is, too.
The UPK-D4's blade is chisel ground which in this case I think is excusable since it needs to sit against its handle when retracted. The back of it is dead flat.
Its taper is about 45 degrees, which is ridiculously steep. It follows that its actual edge angle must be steeper still, and it sure is.
We like superlatives around here: Whatever's the biggest, the thickest, the lightest, the heaviest, the sharpest. Well, the UPK-D4's sure got one -- I don't know if it has the most obtuse edge angle of any knife in history ever, but it's certainly the steepest out of anything I own. 60 full and glorious degrees, by my reckoning. I think that means it just barely even qualifies as a knife.
Make no mistake that you can cut things with this, but in some cases it's really a matter of interpretation. It makes a dandy letter opener, for sure, but to successfully slice most other things you have to come at it with the blade tilted at kind of a reverse angle.
This is not a knife made for shaving, whittling, carving, or slicing tomatoes wafer thin. It is a designed for blocking strikes and stabbing fools. And while there are very few knives on the market where it's truly wise to use them as a prybar, this is probably also one of them.
The Obligatory Disassembly
The UPK-D4 is refreshingly easy to take apart. Just three screws, or five if you include the ones for the clip.
Mind you, all three of the big ones are threadlockered and I found they were also quite thoroughly torqued. The dinky driver handle in your precision bit kit probably won't do it -- you'll want something with a right angle on it, like a Torx socket on a ratchet handle.
The hardware. The mechanism is quite simple, too, with the lock button supported by these two springs and simply raising and lowering in its hole. The locking surface itself is the interface between the head of the locking lug (which is also a screw) and the two pockets it falls into on either end of the track. That's all there is to it.
Here's the lock button's pocket, with its two little locator nubs for the springs.
The Inevitable Conclusion
A lot of pocket knives from the various big name manufacturers, especially those marketed towards the police-fire-rescue types, bill themselves as Specialty Purpose Combat Tools.
Well, they're not. This is.
The UPK-D4 is probably also along the lines of the many folding knives that try to masquerade as fixed blades, a task at which typically fail. And again, this doesn't.
It's precisely what it sets out to be: A dagger that needs no sheath, a fighting tool that actually can cash the checks its looks -- not to mention its product blurb -- try to write. And when we say "dagger" we don't mean "dinky knife that's got double edges so now it's illegal in California." No, we mean it's genuinely suitable for holding in your off hand alongside your rapier if you wanted to.
The only question is, as ever, why? Certainly most people don't actually have a real use for such a thing. But that's never the point.
It is humongous, ostentatious, and unapologetically disregards any notion of practicality or general purpose utility.
That's bold. So for that, I love it.