BCMW ht 3V chopping tests

:thumbup:​
:thumbup: Nathan :thumbup:
:thumbup:​

Nathan, for 3V ht eval between you & I. We could:
a) I send my ~65rc 3v test blade (yeah the one in video with 'shock&aweful' handle). After 2 weeks, send it back along with your 60.5rc 3V chopper. After 4 wks, I return your chopper.
or
b) send me 2 choppers, 1 hardened, 1 unhardened (w/ handle assembly but not epoxy yet). After 2 weeks, I return both. After 2 wks, you ERASE ht on BCMW ht-ed chopper.
* finds/results mostly be kept as confidential - sure, we can yak to our friends about it but no write up.


*** all ***
For high scrutiny public eval: I prefer to go along the line of my proposal in prev post. Metallurgical examinations <= bring 'em on! Hopefully, BSED involves - I would love to get free imaging. edit to add: Just to be sure - I am not contradict my earlier statement about BSED. I don't think there will be a big trail of metallurgical hints/bread-crumbs with 3V. I am comfortable with low Cr steels now too.

For 66rc objective/question: so with Nathan's 65.5rc AQ #, thus 66-66.5rc falls within instrumentation and or conducting/reading error margin. Having stated that, however stubbornly I trust my *hand-waving* hypothesis of 3V potential of reaching 67rc peak hardness. So 66rc would be a low/conservative avg of 5 rc readings by tester calibrated with certified block.

Edge stability at ~65rc objective/question: to be seen/test/verify (if that goes well, implies my 65rc 3v video might actually be real :))

Test blades subject to edge profile changes/mangling and even destruction.

Nathan the Machinist said:
If anyone is doubting as quenched hardness of 66, this is pretty close.
..

^ That's here in my shop on an NIST traceable, certified and calibrated hardness tester. That includes subzero as a part of the quench. I'd consider 3V at HRC 66 to be very possible and simply on the high side of normal.

I'd be glad to send a 3V chopper at HRC 60.5 and Field Knife at HRC 62.0 for experimenting, though if it's going to be compared to someone else's work I'd like the opportunity to reciprocate. :thumbup:
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bluntcut said:
Here is a rough idea, which could answer a couple 3V curiosities: 1) AQ 66rc 2) edge stability at 65rc

Someone send a knife maker (Receiving KM) near my area:

1) a hardness tester ~62rc calibration block, unless this receiving KM already have a block for ~62rc.

2) 2x identical 3V knife/chopper w/o handle, where 1 hardened (preferable by Peters or Nathan) to whatever working hrc, 1 unhardened.

In addition RKM - provide a clean grounded 3V coupon (1" x 3" at least 1/8" thick)

This RKM swing by my place
a) 8AM: drop off the unhardened blade & coupon. Then R&R around the Goleta Beach for few hrs.

b) 1:15PM - enjoy lunch together at Beach Cafe

c) 2:30PM - video hardness testing for: brought along calibration + my blocks; 2 3V blades and the coupon. Exit while I lower the BCMW ht 3V to ~65rc

d) 2:45PM (didn't temper long - hahaha): Video quick hrc reading for 2 3v blades again

e) Video side to side performance of the 2 blades. RKM welcome to bring chopping materials - something hard and challenging but no silliness stuff (like I have in some videos); change hands a few times. Zoom in.

f) Take macro pics of the 2 blades.

g) Make copy for videos & Pics.
h)
option 1: toss BCMW ht blade & coupon into 1500F oven for 10 minutes <= ERASE!
option 2: Pay $500 to keep BCMW ht 3v blade, extra $100 for 66-66.5rc 3v coupon. LOL - this option2 is moot if my ht is lousy, right?

So $ needed for: 2 buy/borrow blades, RKM time, lunch, plus potential $600 for keeping BCMW ht.

Even $1K ticket is so cheap compare to my R&D expenditure.

Disseminate videos & pics to participants. With my & RKM consents, videos & pics can be share on BF by RKM and or myself.

Thoughts/suggestions?
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Luong, I don't want to discount the effort and costs of your endeavors but $600 for heat treating one blade is so high I don't know if you're joking or if you're attempting to ensure someone doesn't take you up on your offer. I don't believe there will be anyone who will provide an already ground blade made of 3V and who would pay $600 to have it heat treated even if it ends up the best. $30 or $40 per blade I could see if the knife does better than what Peters can do. Your heat treatment would have to have 1500-2000% better performance than what you could get with someone else. At the very least it would have to show very strong gains in all respects over what anyone else could do. Is it possible? Sure it is, but to start off charging that even as you're coming out of the gate may be a little off putting. Forgive me if I read your post wrong or misunderstood.
 
Thanks for the advice however a bit misconstrued. Look again, you see there is the 'ERASE' option. There isn't really a need to pay $600 to enter IP game, right?

ERASE = I get nothing for my day and risk possibly of flushing my credibility down the toilet on bad ht day :p

$600 = IP risk because why do you want my ht in this context? So, I think I being foolish, either that or incredibly generous.



bodog said:
Luong, I don't want to discount the effort and costs of your endeavors but $600 for heat treating one blade is so high I don't know if you're joking or if you're attempting to ensure someone doesn't take you up on your offer. I don't believe there will be anyone who will provide an already ground blade made of 3V and who would pay $600 to have it heat treated even if it ends up the best. $30 or $40 per blade I could see if the knife does better than what Peters can do. Your heat treatment would have to have 1500-2000% better performance than what you could get with someone else. At the very least it would have to show very strong gains in all respects over what anyone else could do. Is it possible? Sure it is, but to start off charging that even as you're coming out of the gate may be a little off putting. Forgive me if I read your post wrong or misunderstood.
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bluntcut said:
Thanks for the advice however a bit misconstrued. Look again, you see there is the 'ERASE' option. There isn't really a need to pay $600 to enter IP game, right?

ERASE = I get nothing for my day and risk possibly of flushing my credibility down the toilet on bad ht day :p

$600 = IP risk because why do you want my ht in this context? So, I think I being foolish, either that or incredibly generous.
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Ok, good luck.
 
Nathan,

A 3V bar 0.176" x 1.6" x 17+" is on route to me from AKS. So I will make a chopper with ~11" blade, target for ~64-65rc edge, ~63rc upper half of blade+tip+tang. Edge geometry (default, unless specify otherwise) 0.025"BET, 18DPS.

Option C) We exchange chopper. Return to owner after 4 wks regardless of condition <= certainly can count on me reprofile edge of your chopper to around ~0.01"BET & ~12dps to assess damage mode & extend (I guess - giant edge roll and or ripples) vs my chopper giant ripples or chips :cool:

Let me know, if this option sounds good to you, I will make the chopper and then go PM mode thereafter.

edit to add: Since I just finished cut 4 W2 blanks - 1/4" thick x 10.5" x 1.5" (16.5" OAL)

Option D) W2 chopper instead of 3V: hrc edge 65-66rc, upper half+tip+tang are bit softer via torch.

Best regard,
==Luong





bluntcut said:
:thumbup:​
:thumbup: Nathan :thumbup:
:thumbup:​

Nathan, for 3V ht eval between you & I. We could:
a) I send my ~65rc 3v test blade (yeah the one in video with 'shock&aweful' handle). After 2 weeks, send it back along with your 60.5rc 3V chopper. After 4 wks, I return your chopper.
or
b) send me 2 choppers, 1 hardened, 1 unhardened (w/ handle assembly but not epoxy yet). After 2 weeks, I return both. After 2 wks, you ERASE ht on BCMW ht-ed chopper.
* finds/results mostly be kept as confidential - sure, we can yak to our friends about it but no write up.
...
Test blades subject to edge profile changes/mangling and even destruction.
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^ I get real nervous when people talk about grinding on my work. Powered sharpening is a big concern too. Heat kills a good heat treat, so I'd much rather do any regrinding on my work here in my shop with flood coolant and sharp ceramic belts. Postage is cheap.

I'd like to keep this to 3V, but if you wanted to also send a W2 chopper Jo and I can give it a proper workout in some 2X4's in Jo's Bladesports setup. 65-66 seems crazy hard for a chopper, but my mind is wide open.

To be clear, this isn't some sort of a competition, it's genuine curiosity. I have sunk a lot of time and resources into optimizing 3V for my uses and I'd be surprised if something someone else is doing right now outperforms it. But I'd also be delighted, because we're all looking for more performance. But, if nothing else comes of it, you'll have a good sample to use as a standard when evaluating your own development which is how we all grow. I love things like this because it's always educational and I always learn something I didn't expect.

As far as what options you want to do, I don't really have a preference. Anything you want me to look at, send it. Anything you want to look at, let me know. I have a 3V chopper at 60.5 and a 3V Field knife at 62. Tell me how thick BTE and angle DPS and I'll set it up. Send me a PM where you want me to ship it and I'll try to get it out next week. :thumbup:
 
** I am typing of this so the public know upfront what & where we are going/doing **

:thumbup: Nathan!

Great. I appreciate this opportunity to interact with one of best 3V ht in business. I sure didn't see this coming, as I merely try & share a piece of 3V data to give me a tad of confidence in 3v ht. Look like I got more and hopefully not over my head.

My goal happened to intersect with 3V ht a little bit, so there isn't any competition between us. I've done quite a few startups so naturally many thing could translate into business bottom line, exactly why finding to be keep private between us. Actually, you have more on the line than I am in this niche. For that, I am delighted to be on the receiving end of your good will and open mindedness.

I also share your concern about sharpening quality, especially overheat from grinding; abrasive sharpness and type appropriate for shaping & sharpening. If tests are w/i bladesports params, perhaps you (have a lot of experience vs none) should be the one make the call. However if both blades are easily passed these tests, not much learn. With that thought, maybe we should pick an edge geometry on threshold of pass/fail - perhaps 0.02" BET, 15dps and finished on 5K waterstone (I know, hands of sharpener issue but it's a decent *as-received* start).

Let's wait until I finish a 3V chopper ~64-65rc edge, before cross-ship our chopper. If I feel gutsy, I might toss in 64rc 52100 & 65+rc W2 choppers as well. After all this, if it turn out my hardness tester is bad and or my stuff made from delusion, I will render a public notice & apology for misleading & wasted time.

As always - I am sharing (or in delusion of) possibilites in metallurgy but not 'how' to get there.

Thanks & I will send PM when ready,

==Luong
 
I'm glad beyond measure about this! :thumbup: :thumbup:
Been watching Luong 's tests video & Nathan's as well. It's going to be great even if the results won't be made public, totally understand!
 
:thumbup: to you too, Chris.
Chris "Anagarika";16194244 said:
I'm glad beyond measure about this! :thumbup: :thumbup:
Been watching Luong 's tests video & Nathan's as well. It's going to be great even if the results won't be made public, totally understand!
Click to expand...

Too hot this weekend to grind & ht, so I will cut some more W2 blanks. Bladesports got mentioned - heck oh why not, since I've 2" wide W2 ... segue-entertainment or procrastination unlimited:p
http://www.bladesports.org/knifespec.html

goV9Htq.jpg


Quick - suggests/critics/veto before I cut this 2 BS blanks
 
My prep-ht, for low Cr steels, is very time consuming. So for this chopper batch - 6x W2 1.5W x 16L, 2 W2 bladesports, 1x 52100 1.5x15L, 1x O1 2x17"L <= hopefully I can shove or stack these pieces into a cramp 18" deep oven.

Main objectives: i) verify my ht resolved large thermal mass issue. ii) if good, sell a few to buy supplies. maybe/optional iii) send a w2 bladesports(better of 2) to Nathan.

My 10" serrated grinder wheel vibrates more than before - a bugger but still fun to hog metal with. Hopefully I can profile 7 choppers tonight. Pre-ht grind later in the week when the heat wave is over. Thought of trying 1 post-ht hollow grind 1.5" wide chopper.

Chris "Anagarika";16196442 said:
If it helps making comparisons more standardized, go for it!
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edit to update: sweaty managed to profiled most choppers, except yet to hand file tricky spots on bladesports blades.
 
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A break from my boring sw dev...

There are doubt & my second-guessing whether my hardness tester is totally off. Searched on opinel carbone hrc -

http://www.opinel.com/en/the-brand/know-how/blade?domain#redirect
We aim for 57 to 59 HRC on the Rockwell hardness scale for our blades.
Selecting a steel grade is always a compromise between mechanical strength and resistance to corrosion. From our years of experience, we have chosen two main grades.
​

My tester consistency read 57rc for my opinel#8 carbone. Reading area is near spine, so it's quite flat, worse case = report 1rc lower than actual because of blade flat (and minute tilt angle?).

So between calibration block & opinel carbone hrc readings, my tester should be +- 1rc against certified setup.


bluntcut said:
Aah good idea, since 65rc 3V chopping blade sounds suspicious...

HRC testing [calibrated block; opinel#8 and then this 3V blade] https://youtu.be/Bkf4zsAWmr8
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AKS package arrives today - I will cut & profile 2 choppers: 3V and 0.196" thick aebl. Cool if I can ht a aebl chopper with working hardness at 65rc +- 0.25rc. Large thermal mass & lot of Cr inclination toward 64rc or lower.

ok: back to work & worry :yawn:
 
This is unbelievable (ok, I believe it :D) - open AKS (Alpha Knife Supply) super secured package. Woah hey, Chuck (AKS owner) gave me 2 bars of 8670: .172" thick x 2"W x 23.5"L and .102 x 1.5W x 23.5L. :thumbup:

In consequence of Chuck's generosity, I now want to make a chopper out of 8670. I will send AKS an invoice for my T&M ;) No good deed goes unbill!

https://www.alphaknifesupply.com/zdata-bladesteelC-8670.htm
Help - need ideas how I can ht 8670 to 65rc?
 
Well, I also will make a half-tang 3V field knife. If I manage to harden 8670 chopper (longer than bladesports) to a working hardness of 63+rc, its life mission will be cutting an old ironing board to small chunk to fit into a recycling bin.

LEKngyV.jpg


W2 choppers. Wait a minute here - 8670 gets all the fun... W2 will be there too :p

YmmBWdO.jpg


Funk tang = 3 fingers or index+palm handle positions. Easy change to full tang if doesn't work out.
 
Well, I heat treated a 3V chopper & a half-tang field knife. Made a little video showing rockwell hardness reads.

Warning - it's a boring rockwell hardness testing video. However exciting if you are interested in steel heat treatment because of 3V 66+rc :D

[video]https://youtu.be/H38P7Z-A8Tw[/video]

Sharpened that half-tang field knife - still at 66+rc. Edge geometry: 0.025"BET, 16dps. Chopped: pine, oak, olive - passed. Whittled: beef rib bone, 16d common nail - passed. I might keep this knife at ~65.5rc working hardness.

update to add:
tDF2LjR.jpg
 
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I've noticed this type deformation at high hrc for aebl and d2 as well. Fracture (big chip) will occur when side/lateral load is excessive.

In chopping (not baton/pressure cut) that small nail. Start out light chop with wood backing, gradual increase velocity and then switched to steel column anvil backing. What I don't know and not ready (time resource) to find out whether these 2 blades can take excessive sheer impact. i.e. hammer blow to spine with 1/3" offset from edge on nail.

I think/conjecture, free alloying elements in this 66+rc matrix act like balls bearing in response to force > yield. Although this matrix macro hardness is 66+rc, I think nano hardness is a few rc points lower due to alloy padding.

Today, I will thin field knife to ~ 0.015"BET and put 15dps bevel. The chopper was grinded too thin pre-ht, hopefully edge geometry won't falls below 0.018"BET for 16-18dps.

Chris "Anagarika";16210771 said:
Luong, what's up with the wavy lines?

66HRC chopper that doesn't chip? :eek:
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Well, look like I will put handles on 3V chopper & field knife. Yes, both blades are 66+rc throughout, so easy to find or make a flat spot to rockwell test.

BluntCut MetalWorks 20160624
CPM 3V 0.172" thick, 16.6" OAL
Hardness: 66+rc = yes, very high
0.02"-0.025" behind edge thickness
sharpened: 14-15 degrees per side (28-30 degrees inclusive)

Chop: 2x4, pine, oak, olive, lignum vitae argentine

Thanks for watching this 11.5 minutes video & comments.
[video]https://youtu.be/HH_EYiL0zF8[/video]
 
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bluntcut said:
Well, look like I will put handles on 3V chopper & field knife. Yes, both blades are 66+rc throughout, so easy to find or make a flat spot to rockwell test.

BluntCut MetalWorks 20160624
CPM 3V 0.172" thick, 16.6" OAL
Hardness: 66+rc = yes, very high
0.02"-0.025" behind edge thickness
sharpened: 14-15 degrees per side (28-30 degrees inclusive)

Chop: 2x4, pine, oak, olive, lignum vitae argentine

Thanks for watching this 11.5 minutes video & comments.
[video]https://youtu.be/HH_EYiL0zF8[/video]
Click to expand...

Luong,

The grind line on the video shows clean and flat. The chopper works well. With BCMW HT, a stainless (less maintenance concern) will be very desirable! :thumbup:
Especially for coconut processing, you don't want the patina blackened the nice white flesh;).
 
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