Bird & Trout knives are small thin fixed blades, lightweight sharp knives able to process a bird or a trout. Those knives got of course no chopping purposes and no bushcrafting purposes but we have found the Sprig by Phil Wilson to be a reliable wood companion.
I already knew Phil Wilson as a knifemaker and clever metallurigist for his writing on CPM420V (S90V) back in 90’s. He was the first to provide fillet knives for people who process salmons all day and was measuring the edge retention of this new powder steel back in the past century. His results were outstanding: the S90V steel was able to process much more fish than the normal stainless steel used on that time (440C ?). He was also able to heat treat them to 60HRC and higher. Bringing the powder steel edge to uncharted territories long before people were spoiled with S30V and S110V and Elmax…
When Phil Wilson did edge holding test, lower Rockwell numbers yielded much poorer edge holding in real world use. High hardness prevents rolling and blunting of the edge, a major cause of loss of sharpness, even though the steel has very high abrasion resistance. His blades do have very high soak temps, oil quenched followed by deep cryo in liquid nitrogen but he did not have any problems with chipping as he considers the use for his S90V knives to be only for slicing. (source Bladeforums).
To quote him:
“Edge holding will be proportional to hardness to a large degree. Experience with CPM 10V, S90V, and 3V showed me that, with a particle-based steel, the hardness can be pushed a little higher up the Rockwell scale and still retain enough toughness to prevent edge chipping. (CPM S60V is the exception; it has it’s best qualities at about Rc56.) This is because the particle-metallurgy-based steels have a very fine grain structure.”
Let’s quote Phil Wilson about knife making and steel testing to understand the way he design knives, this is from an article he wrote in 2002 about the coming of S30V then new to all 15 years ago:
” I chose to make a fillet knife because, in my opinion, it has the hardest work life of any knife. Use around salt water will reveal a fillet blades ability to resist corrosion in a short time. Edge holding is tested quickly when cutting through scales and bones and working against an abrasive cutting board. A fillet knife must have a thin, flexible blade to ride over the rib bones during the fillet cut. A brittle steel will soon chip out or break under such use. A fillet knife also makes a very handy kitchen blade. It’s a natural for boning a chicken breast, slicing prime rib, or filleting out a grapefruit. Kitchen knives are left wet on the counter and bounced around in a drawer with other utensils, which is another pretty severe test for a new steel.
In addition to the fillet knife, I made a simple slab-handle semi skinner with the new S30V, and two other [nearly identical] knives from CPM S90V and 3V. This effort would give me a fresh comparison on the heat treating, grinding and finishing of all three steels. It would allow me to do some cutting and edge-holding tests against the new grade. Does the new S30V meet the challenges? The answer is yes, and I’m willing to bet that it will be the favorite steel of many knifemakers in a short time.”
— August issue of Blade Magazine in 2002 —
So as you can see Phil Wilson knows his craft and was testing those new particle-metallurgy-based steels to their limits. No surprise Jim Ankerson and Sal Glesser are huge fans of Wilson’s knives.
The Sprig is not the first Spyderco edition of Wilson knives. The South Fork FB30GB was the first. This design combines very high cutting ability, point penetration and grip ergonomics into a very high performance working knife, to quote Cliff Stamps test of the custom original version. Strangely I was never able to bound with the South Fork when with the Sprig it was love at first cut !!
First thing was the handle. The rounded Sprig handle is much more confortable in my hand when the South Fork feels more square. The Sprig is nested in my palm very very confortably and I can cut i wood for long time without any hotspots noticed. It’s important for a fixed blade. With folders there is often some kind of compromised due to the folding of the blade into the handle, but for fixed blade the confort during cutting needs to be optimum hence the Mora’s handles compared to any thick edged squeleton tactical gadgets.
The Sprig is great on wood, even with its factory edge. It is ground thin in Taichung and is able to get to work right out of the box. The belly also helps a lot to push cut fibers acting like a guillotine edge. So really this knife can be used for bushcrafting purposes which are not implemented hard drilling in wood or batoning. The thin point is wonderfully handy and not made for snuff Russian tests.
But for cutting wood and whittling the Sprig is even better than the South Fork or the Gayle Bradley Bowie and Junction, because its edge is so thinly ground.
I had used some diamonds on it but it was not really necessary really. Just a compulsive attitude of mine when I got too much time on my hands… S90V is a legendary steel. I already quote Phil Wilson’s articles in my Paramillie 2 review.
“Crucible Materials Corp has introduced three winning steels in the past 10 years: CPM S90V, CPM 3V, and now CPM S30V. CPM 3V is still the undisputed toughness champ, even surpassing some carbon steels such as A-2. Originally known as CPM420V, S90V was introduced as an upgrade for S60V (originally called CPM 440V), and met all the targets of improved corrosion resistance and toughness. It has the reputation of being hard on heat-treating equipment and is a bear to finish, but is still the best edge-holding stainless steel going.”
Easy to carry in my denim pockets with its kydex sheath, the Sprig is not really bigger than the Sliverax. The sheath is well made and flat enough to be packed in any Go-Hunting bag. So it’s very easy to bring him along for a walk in the forest or near the sea as S90V is very stainless.
I was really surprised by the cutting abilities of the Sprig. It really caught me by surprise.
The drop point design is useful even in the kitchen , so the Sprig will suit hunters as much as cooks and also it will take a very serious place in any expeditions needing a reliable cutting tool which you won’t need to sharpen every hours.
You can find a lot to read and learn in Phil Wilson’s site here: