Strain/stretch is a critical requirement for a good working sword, where M2 and high carbon steels lacked thereof possible to make a thick/broad but not flexible sword.

@@BluntCutMetalWorks Interesting. So it's not elastic enough? I'm not a mechanical engineer at all, but I like the toughness and hardness of these high alloy steels. Is there any kind of high speed steel that could suit this purpose? I mean, normal non-alloy high carbon steel is great for this purpose.

@@bilbo_gamers6417 It sure can has full elasticity range but I stated strain/stretch tolerance for these steels are low, thereby having narrow plasticity range and essential no necking/elongation. HSS ht to low hrc and also high % of cobalt matrix steels should support reasonable functioning sword. To support activities induce high impact/impulse and acute bending radius, material need at least 10% elongation, else material would unzip (uncontrolled crack propagation) into 2 pieces. That is why, working swords out there have ~40-54hrc and 0.5%C martensite matrix (note matrix, not overall composition).

@@BluntCutMetalWorks Very interesting point about elongation. So it wouldn't be possible because they can't elongate? By the way, I ask because katanas often have HRC of around 65 but they are very stiff and not designed to flex as much as European swords

@@bilbo_gamers6417 Right and agreed. 65hrc is the ceiling hardness for slicing tools - esp pertaining to katana. On avg katana has around 0.7-0.8%C low alloy steel. Also unlike low flex broad sword, katana would performs poorly/badly/broken on metal to metal interaction, unless it ht-ed sub 50hrc. broad swords leverage mass/bulk/blunt force. Sword required ductility, wear resistance is a nice-to-have. Keenness (dull resistance, stay sharp longer) is inverse proportional to ductility. Si02 is around 64rc, so higher hrc stay sharp longer in natural usage.

Appreciated!

Thanks

Make one wonder about their company metallurgists heat treating ability eh ;)

Extra weight and chips removal geometry are critical elements for fast chopping this hardwood. Extra thin upper cheek promotes deeper penetration hence harder on the thin edge and not enough deflection to bounce/kick chips away. I did thought about doing a big log challenge... maybe at a later time.

Thanks. It was a little un-nerving when swinging fast, edge seems too eager to go beyond intended depth :)

LOL - the first 2 times of wired-edge, they look perfect and were easily removed by bending side-to-side with finger; however edge below already concaved. At time, these attempts feel 'futile'

I like it too, a few of these blades/blanks are waiting for next few sequences.

52100 is much easier to ht (even blind folded :D), O1 easier to screw-up but can exceed best 52100

Thanks

Edge deflection always at-play when chasing either ultra-thin angle or ultra-keen edge when shaping/sharpening with plate abrasive.

Oh man chasing a wire edge on a knife like that sounds mind melting. Again, providing excellent information for the community.

I need to go forth with another experiment, thus reason for not zero-ffg again but settled for 3 dps instead was aim for 2.6 dps.

Well, thus far O1 around 64rc well suited for/if this pursuit ...

Interesting!!

10v can yields up to 69.6rc AQ, hence 66.5rc isn't is definitely within normal hardness. Thanks.

Thanks

Well, test samples/specimens are still displaying somewhere, so EDS them to know however nobody probably care...

Hey cool - swimming/diving sounds really fun, water temp? I was an ocean swimmer for 15 years, still can swim but toes & fingers hate me when water temp below 20c/68f :)

Thanks. Hèn chi cái búa nầy nặng quá chừng, chỉ có Thạch Sanh bửa nổi thôi ;)

Thanks

Thanks. Sciences must apply, otherwise voodoo/delusional

Thanks for asking, For the last 3 years - I/BCMW mostly stopped selling/listing knives to general public. Occasional sales are still happening for those following my/BCMW works.

Right! Also I think - chainmail sock alone won't be that helpful minimize the damage from an axe strike - impact force is too high, hence cushion is required to enlarge the contact area (thus much lower psi).

Thanks

Thanks. Original blade has 60 degrees cutting edge and 45 degrees bevel, thus hardly penetrate and re-bounce energy hurt arm & shoulder :) It was fun chopping stuff and increased my stamina at swinging heavy axe.

Thanks. It was fun chopping and probably will clear the stream later when it dried up

Yup, it is nifty thin axe bit and geometry. I was quite gentle with delimbing swings.

Agreed.

Sure it would... I've a double bit head (I cutoff the bits), will make this one when time permits

See previous video - cruforgev trail clearing - 2+1 persons crossed at that trail section. There are still a large branch around thigh high blocks the path. It is almost dried now, I plan to buck that log and 3-4 others closer to the ground later on

Sure, a 8+mm thick rex121 69+rc would works in the khukri shape but wouldn't work as an axe bit

@@BluntCutMetalWorks one knot and a chunk is gone

@@adanma17 Khukri edge geometry is very stout, it is more of a smasher than cutter. rex121 axe bit this thin would fail in 1 swing :)

Nod to an ultra trail runner walks his dog

It has 30 degrees micro-bevel (cutting edge). If chopping pine or douglasfir (soft log), 15 degrees would be fine but blue gum is 5 times harder hence need 30* micro. For a normal 58-60rc axe with 15* bevel and micro like this, edge will mangle badly when chopping blue gum (~2400 in janka hardness, note: white pine janka is 460).

@@BluntCutMetalWorks Nice work, so salt forging seems to be better for several types of steel...cool

@@8thsinner Not sure what you meant by salt forging? I like to forge but don't have a facility for that - ideally an isolated location (way away from ppl) with 50Kg power hammer... So, my research is mostly stock removal and harden using ht oven.

@@BluntCutMetalWorks I figured this is what you meant when you said in another comment that you're using unconventional systems. Never mind.

@@8thsinner BCMW hardening process takes 1 to 30 days (currently around 2 days, est 50-70% from optimal) vs conventional ht takes 5 hrs. BCMW process in production will takes 2-3 hrs. Crystal Science/physics is elegantly simple but conventional metallurgy is an empirical/stochastic art.

Thanks.

@@BluntCutMetalWorks o1 isn't suppose to do that

@@huckstirred7112 Right on, O1 is very brittle - esp at 60+rc - when ht using conventional/industry protocol.

Thanks. I sharpen with diamond plate, although a AlO stone would be good as well. This blade is 62.5rc which is way harder than most file on the market.

Blue gum heartwood is sure hard - acts similar to dried Honduran rosewood. Pleasantly surprised this bolo edge didn't blew out large crescent shape chips.

A bonus - I got a few 'thanks' from ppl for opened up the trail

Wrapped the bit edge with very wet folded paper towel will keep the edge from over-heating. No problem touching the edge with fingers during and right after weld.

@@BluntCutMetalWorks ok i get it , thanks

Larrin did tested a few set of un-notched charpy specimens for me. Excellent results however I need much faster turn around time. My tests are relative/against control specimens, so a certified pendulum charpy tester is nice but doesn't needed nor will enhance signal/noise ratio, especially when my #s are 1 to 5x relative to control. I started out with un-notched samples but they kept destroyed the carbide striker head due to high ft-lbs, hence switched to notched samples, of which around 1/10 ft-lb of un-notched.

Well, gotta kept all other variables, esp geometry, equal/same when testing ht performance.

@@BluntCutMetalWorks Which one is better for fighting knife 52100 or A2?

@@ThirdoptionJCSU 52100 supports higher/more bend/flex (for same thickness) thus blade less likely to fracture/split when subjected to prying motion... than A2

@@BluntCutMetalWorks Oh great!I DOnt have any A2 knives but all my choppers are in cpm 3v,52100,5160 and O1.There is a guy i think he is Japanize and he makes videos here on youtube saying that A2 is a way better than 3v .He compared 2 Bark river knives.Also he said that A2 is a way sharper than 3v.

@@ThirdoptionJCSU Blind chopping tests(all things/conditions equal) of good ht a2 vs 3v. A2 would performs slightly better than 3V. "sharper" is not a valid qualifier nor quantifier.

Certainly.

Hardness is easy, producing high hrc with full elasticity and decent plasticity ranges is quite difficult. High alloy steels have poor structural toughness. Thus far, aebl produces low notched impact toughness #s compare to lower alloy steels, esp very low (i.e. carbon steels).