The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details:
https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is $300 $250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
Chris "Anagarika";15933247 said:...
I think people might start to get impatient, when is production date is.
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... Thanks, Chris!Chris "Anagarika";15949772 said:
[but only because you push them to the brink and beyond to see where the brink is!)
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Very interesting "WIP"
I'm on "the edge" of my seat
I have to confess, although I think the rigorous testing will lead to a robust product (JEST bolo!!), I keep thinking that BCMW knives always break
Chris "Anagarika";15957014 said:I have to agree with Chiral ... Controlling one aspect will give a more meaningful reading.
His last paragraph about keeping the apex constant while changing the BET will also help us following the progress.
I also know that you know this already & keeping track of the test database on your records. It's just that we're anxious with the launch date
OK, another quick one:
Luong, why not keep every edge at 15dps/20micro when even the 65Rc W2 (with what, 2% carbide amidst the matrix?) ripples/chips in the tests that may simulate actual use by future customers? What i am seeing in your results is that it doesn't matter how much or how little carbide you have in the apex steel, it's going to suffer below that geometry either by fold or fracture. So why mess with the geometry of the very apex when you already have a good idea of the threshold of sustainability, and beyond that threshold it can be very difficult to control the user-applied forces and responses in the cutting medium - the scale is just so small and the forces so high. Not to mention that increasing the apex angle from 10-dps to 15-dps reduces your mechanical advantage minimally (from 23% of optimum to 14% in just the very very tip of the cutting) while increasing your edge-strength 3.5X ? (I think i did the math right)
Feed the apex what it needs to survive, to sustain itself. If you don't see damage at 67Rc at 10-dps after a few hits, does that mean you won't see damage after 100 hits? Each hit is unique, each has the potential to induce failure if you are riding so close to the threshold of structural integrity. If you build your knives with too thin of edge geometry, it may survive the test this time but not next time, or may fail in this way this time but a different way next time, it is becoming too hard to reasonably control the variables. When we build a structure, we calculate the expected loads and then overbuild to sustain the structure above and beyond what is expected.
Setting your apex geometry to 15/20micro should get rid of damage in the edge-bevel (micro-chips and rolls/ripples), if your observations hitherto may be relied upon. If you have a problem within the edge-bevel at that geometry, you know that something is wrong.
Then simply modify the BET for each blade as you have been doing - 0.005, 0.010, 0.015, 0.020 - to provide the required strength in the primary of the blade to prevent massive "moon-chips". An edge that dulls can be resharpened. But a primary that fractures = unusable blade. Your knives, regardless of HT, will dull with use, so just give them an apex that can reduce major failure (including crack-nucleation) and work instead on the HT that allows the thinnest primary for maximum efficiency.
I know you know all this. But I want you to simplify to get your R&D into production more quickly
Your highly analytical reasonings are well appreciated. I agree that geometry (volume) is cubic while ht improvement is more/less linear, so hold dpses fixed while varying BET is easier to correlate and track. My tests varied both variables to keep geometry as cubic for both lateral & perpendicular. Amplified forces to see differences over time, even though high variance in small samples set. Yeah, data does somewhat look like a tangle mess & cost a whole lot too
Posted & private data are triangulating/confirming my theories (call them conjectures if you like) on microstructure. Now, I am confidence that my macro+micro+nano hardness/strength assertion is accurate. Also observed 2nd & 3rd attributes (non-disclose) contributed to matrix coherence and its impact load. 4th is to delineate between toughness and ductility. 5th is mode of ductility can increase&decrease impact load and gross increase in working apex radius, especially when edge steering involved.
The half moon-chipped D2 is a clear example of macro hard (high dislocation) but micro&nano wimp. Steered & pileup/plastic-work-hardened doom it. This blade, even lowered to 60rc, it will get softer and will still be half-moon chippy. Maybe a 56rc sort of stabilize it - albeit a hefty wide working apex.
While my other 64rc, once lowered to 60-62rc it will be less strong but gained toughness. My projection is that they won't get degrade into undesirable ductility until sub 59rc. As I posted about homogeneous microstructure... this 56rc would far stronger & tougher than the half-moon ugly D2 cousin.
I think a user could easily tell the differences between(a working BET/dps near sub micron apex radius) 0.01"/10 vs 0.015/15 vs 0.02/20 vs 0.03+/20 for EDC and works.
My current test plan is primarily with D2. 4x 3.5" blades -> 2x 4-5" 64-65rc blades -> 2x 5-7" 63rc bowie .156" thick -> 1x 62-63rc JB .187" thick. LOL - took me about 2 yrs to see some daylight on a D2 chopper
After that applied new knowledge to ht low Cr steels (W2/52100/etc.) - make some test blades. As a bonus, hopefully resolve inconsistency microstructure for stock thicker than 0.140".
Launch BCMW.
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