I had from the beginning intended to offer these knives in a range of options and sizes. Particularly a smaller, more pocket friendly version for EDC.
K'roo knives are built to work - and to last. These are built the same way - to be very strong indeed, but also more attention to detail and level of finish is given. This knife is the next in line.
Please bear in mind it is a proto-type and that I have already noted a few small changes and or alternative options I would offer on production models. We'll get to those at the end of this thread.
Design brief:
- a serious Working Knife (hence the WK in the model name) but slightly smaller than the big 90
- the design must be able to be easily adapted for integral frame lock/ liner lock, Friction Folder and Slipjoint, should there be interest for a UK legal EDC model, which precludes locking knives
- with the above in mind this one has a 75mm (3") blade. In addition to this, a good 3" blade will do most day to day tasks in any event.
- The blade design must work equally well with a convex, flat or hollow grind, to allow clients to choose the option best suited to their needs
- handle design must be such that it would handle well when wearing gloves and be comfortable to use bare handed, with no sharp edges to rip your hands to shreds
- I made the blade slightly slimmer to go with the 3" configuration - it is 3.25 mm (1/8th) N690. Why stainless? Well, it is lower maintenance, often a plus on a working knife. And, it is what I had on hand.....
- handle must be comfortable in as many grip positions as possible
This specific model, the WK 75:
- the big Ranger 90 was designed as a specific custom knife and combines a Friction Folder with a liner lock (integral frame lock) and the WK 75 can be done in the same configuration. This one however is a straight forward liner/integral frame lock...well, almost
- having said that, I wanted to incorporate some of the FF features without having sometimes bothersome tang of a pure FF as this one is suitable for pocket wear
- to achieve this, there is ample area in front of the pivot, to allow for a longish extension to the tang without it sticking out too far "in front" of the knife when closed. I wanted this feature as the tang first of all offers a little of the FF's security when held, but primarily as it would transfer torsion stresses to the liners, rather than the pivot
- the slight bit of the tang that protrudes when the knife is closed works well for one handed opening.
- after some discussion with a good friend, and knife fundi, I decided to drop the point on the blade a little more than on the Ranger 90, as being slightly more versatile for general use.
- I put a hollow grind on the blade, as this is one of the options available, I had already done the convex on the 90, and for general use the hollow is probably a better choice as it will slice better than the convex.
Design stage:
I chose the bottom of the two designs, with the point of the blade dropping more
Drawing out the templates. I did a quick mock up drawing of how the knife would look closed, and I like it - simple, nice low profile, will fit the hand well in the closed position too:
Cut outs, rough:
Profiled, pivot hole and rear hole for lock drilled:
In this series the knife is initially shown with the initial grind done, an just initial fitting, later on the HT had been done, the final grind applied and more detailed checking for fit - you will note that in the first pics there is for instance no lanyard hole drilled and later on there is, as I progressed:
Once I was happy everything fitted well together, it was time to do the short, end cut, on the lock.
On this lock I decided to take a different approach than on the Ranger 90:
- On the 90 the lock is pure brass which I believe will give many years of good service, as proven by the likes of Camillus, Camco, Imperial, GEC etc etc with their brass liner locks - while it is softer than steel it is very "slippery" and wear resitant. In addition to this, the liner lock is assisted by a full friction folder tang, to take a lot of stresses off the liner.
- On this specific WK 75 there is no full length FF tang, so the lock will be absorbing more of the stresses. I have also been reading up on the problems a good many seem to be experiencing with especially Ti frame/liner locks, with wear etc causing lockrock and or binding/galling. So on this one I did a steel insert on the end of the lock.
- The steel insert is N690,l but not hardened. The thinking here is that you are going to get wear over time, no matter what, and having two hard surfaces wear on one another would probably result in the same amount of wear over time as one harder surface wearing on a softer one. AND, if you have to have wear, rather have it on the insert, which can be replaced when needed, than the blade, which is a lot more difficult to replace yourself.
Please bear in mind when these pics were taken everything had just been "rough" assembled and will still be worked off quite a bit more:
The insert:
This one is riveted on, on production models it will be removable:
Knife open:
Closed. If anything is slightly off center, please bear in mind that the knife has only been "pressed" together and isn't tight yet - and there is quite a bit of sideways pressure and torsion from the lock:
There is no detent ball in this knife, for the following reasons:
- I had none on hand...
- I am not too convinced it is needed - first of all, the pivot screw is adjustable for tension, so the ball would not need to play any role in keeping the blade closed, secondly, the pressure from the lock against the tang of the blade is the same with or without the ball, thirdly, the friction of the full lock face on the tang is more than from the ball alone, insuring security when closed, and lastly, due to the extended area in front of the pivot, the section of the tang that might pick up circle marks from the lock does not protrude beyond the scales, so is never seen.
- having said all that, it will be offered as an option on production models
And here it's done.
It is just a proto-type, built mainly to see how it works out when scaled down a little - and I am very happy with it. There will be small changes to production models, but essentially this is the knife.
Blade, in this case, is 3.25mm N690, as is the back strap, brass liners and fittings, with an N690 stainless steel insert for the lock, Wenge scales.
As can be seen from the pics, I cut a false edge/swedge on the front of the blade. On production models this will be optional.
I added a little jimping to the tang, to assist with OHO:
False edge/swedge seen from the business end:
From the top:
Blade is handrubbed to 600 grit satin - this will be the standard on production models too. Finer grit finishes will be available as optional extras.
Here it is with a pocket clip fitted - I have since removed it and am carrying the knife just in my pocket - it has become my favorite EDC.
Changes/options to production models:
- It will be available with a variety of handle materials and steels
- it will be available with either brass or stainless liners/frame, if brass, it will have a steel lock insert
- It will be available as a liner/integral frame lock, liner lock FF combination, pure FF and slipjoint. A back lock model might well follow.
- Steel inserts will be replaceable
- Detent balls will be offered as an option
- Any reasonable and achievable modification/customization you might want.
These are priced at $250, without the pocket clip and detent ball, but including postage and PP fees. For the pocket clip add $15, for the detent ball, add an additional $15, both supplied and fitted.
Comments welcome as always!
