For over forty years, it has always been my goal to produce better and better knives. I achieve this through continual research, testing and refinement. The value of my knives is directly related to extremes in sharpness, edge holding, toughness and durability. Even in used condition my knives have proven investment value. https://seanmcwilliamsforge.com/shop-testimonials/
Three Test Blades
For this test, I made three blades, all from the same size bar of CPMS35VN stainless. All were flat-ground. Top blade was just ground, shorter than the others. Middle blade was forged and tapered, bottom blade was forged, tapered, and edge packed. All three were heat treated, tempered, and sharpened the same. Heat colors on the blades show a hardened edge and spring tempered backbone.
Cutting tests were made on double strength corrugated from one appliance box. This ensures comparable test results, since cardboard varies widely. Cuts were spaced 1″ apart and 32″ long and number of cuts recorded for each blade. Cutting was stopped when the blade would no longer make a clean cut all on the same paper.
These results prove the value of forging and edge packing. First test proves that S35VN is a superior steel, even for stock-removal blades. Second test proves that forging improves edge holding nearly 3X . Third test proves that forging and edge packing adds almost 4X the edge holding to a blade. https://seanmcwilliamsforge.com/the-cutting-power-is-why-i-forge-stainless-steel-knives/
Forging Improves Toughness
The ground blade showed the toughness of S35VN, finally snapping past 25 degrees.
The forged blade bent to 40 degrees, breaking at 45 degrees.
The forged and packed blade bent past 60 degrees, breaking at 68 degrees. A definite improvement in toughness!
A Look Inside the Steel
Now for the hard science, three more test blades were made and heat treated the same way from the same steel and sent to a metallurgical lab for Micro-Photography. This allows a closer (500x) look at the grain structure. the photos clearly show the differences in grain structure of the blades. But, I didn’t really see the effect of packing until I enlarged the high resolution photo full screen! Then I could see there was something happening at the edge, The chromium carbides appeared organized like stacked stones of a defensive wall. Clearly, not random. This is the effect of proper edge packing. The photos here are lower resolution. So if you want to see this for yourself, I’ll be glad to email the full size photos. When it comes to blade steel: “It’s what’s in it that counts.”
Stock removal blade shows uniform fine grain throughout the blade. Forged blade shows grain refinement at the edge.
Bottom photo shows further grain refinement, and tighter grain at the edge. The carbide structures are definitely not random as in the ground blade, and forged blade.
So draw your own conclusions, I have. I look forward to your thoughts in the “Comments” section below.