Where to buy thin 3V

bluntcut said:
Consider wharncliffe edge for steak knife - point contacts plate surface = non-cutting dull point, while the rest of edge cuts steak = remain sharp a long time. Also slowly over time discourage users from trying to cut the plate in half using the tip because of pointlessness in doing so. Toughness still needed because of bone contact (get last bit of yummies from tbone and ribs). Wear resistant maybe more of a bragging than a should have since meat isn't loaded with abrasives.

3V & Zwear are good choices for steak and fillet knives ~61rc but so as many other steels. 61rc k390 0.05" thick 6" blade fillet knife with drastic distal taper tip would support 90* elastic bend but it won't supports plough through fish hard rib bone with thin edge geometry (e.g. ffg distal, 15dps, sub 0.01" edge shoulder). Due to limited stock thickness options, maybe buy 0.093" zwear and surface ground it to 0.05-0.06" before or after cut blanks. Before making a set of steak & fillet, maybe pilot this project with inexpensive A2 or zfinit - it might win spots in your knife block.
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Thanks a TON!!! I really like the idea of a wharncliffe design. I hadn't thought of that. I'll make a pair out of 01 since I can heat treat those at home (cheap, quick, and dirty... really dirty). It will give me an idea as to whether or not the geometry will be acceptable in use.

I didn't realize that the K390 would flex that far. That should be PLENTY. For fish, I just deal with panfish (bluegill). Sometimes by the hundred, but no really hard bones. Big concern there would be boning out a deer. I don't jab the blade into the meat, but I do need to be able to do some plunge cuts where the other end is the spine, or part of a shoulder blade. I'm guessing that so long as I use some common sense, I should be fine.
 
Just in case you missed the "drastic taper tip" part - big part of flex is proportional to thickness = drastic taper/thinning tip = more flex(h is thickness in https://en.wikipedia.org/wiki/Flexural_modulus). However at 61rc k390 should has close to full elastic range as 3v/4v/xwear.

Good idea to prototype edge profile with o1...

fields_mj said:
Thanks a TON!!! I really like the idea of a wharncliffe design. I hadn't thought of that. I'll make a pair out of 01 since I can heat treat those at home (cheap, quick, and dirty... really dirty). It will give me an idea as to whether or not the geometry will be acceptable in use.

I didn't realize that the K390 would flex that far. That should be PLENTY. For fish, I just deal with panfish (bluegill). Sometimes by the hundred, but no really hard bones. Big concern there would be boning out a deer. I don't jab the blade into the meat, but I do need to be able to do some plunge cuts where the other end is the spine, or part of a shoulder blade. I'm guessing that so long as I use some common sense, I should be fine.
Click to expand...
 
bluntcut said:
Just in case you missed the "drastic taper tip" part - big part of flex is proportional to thickness = drastic taper/thinning tip = more flex(h is thickness in https://en.wikipedia.org/wiki/Flexural_modulus). However at 61rc k390 should has close to full elastic range as 3v/4v/xwear.

Good idea to prototype edge profile with o1...
Click to expand...

Wow, it's been a LONG time since I've looked at those equations. I didn't realize that the steels elastic properties were quite so dependent on thickness, but it does make sense both mathematically and practically speaking.

Yeah, I caught the taper tip part. Plan would be to taper down to .020" length wise. Realistically, I'm not actually interested in the tip alone flexing. I'm more interested in the blade being able to bend over most of its length. Hopefully, the .040"/.050" will be thin enough to allow that to happen to some degree. I don't need to bend 90 degrees, but 30 would be really nice. I'm guessing that I should be able to get a general feel for that on an 01 prototype as well. Should I have any durability concerns about K390 (vs 3V) on thin blades like these?
 
Alpha Knife Supply said:
We received part of the shipment: K390, N690, 440C, D2 & Vanadis 4 Extra. We are still waiting for M390, Elmax & Vanax.

We will have them back on website as soon as they arrive.

Chuck
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Thanks for working hard to make nice steels available
 
Ordered some k390, got to get it while the gettings good. Hope it's a restock when it's out. Not sure if folks realize how special that stuff is.
 
Use Bend Allowance Calculator would answer the how far your blade could/would bend. K-factor is around 0.5.

There would be some durability different, depends on range of deflection within elasticity [true, proportionality, limit]. Proportionality start(scatter back/forth plastic movement) and end of K390 is lower/narrower than 3V... or when flex is stress = steel fatigue factor. Having said that, I think (because I hasn't observed blade failure from fatigued yet) flex cycle of mid elastic range for k390 would out last the consumable life time of the blade. If interest and resources allow, make a k390, zwear, 3v fillet knives - fun to have 3 to test long term use (loan whichever knife to a fishing bud). Oh heck, aks has thin aebl and 440c, why not try them too. With good ht (such as Peters), you probably hoard all 5 :)

fields_mj said:
Wow, it's been a LONG time since I've looked at those equations. I didn't realize that the steels elastic properties were quite so dependent on thickness, but it does make sense both mathematically and practically speaking.

Yeah, I caught the taper tip part. Plan would be to taper down to .020" length wise. Realistically, I'm not actually interested in the tip alone flexing. I'm more interested in the blade being able to bend over most of its length. Hopefully, the .040"/.050" will be thin enough to allow that to happen to some degree. I don't need to bend 90 degrees, but 30 would be really nice. I'm guessing that I should be able to get a general feel for that on an 01 prototype as well. Should I have any durability concerns about K390 (vs 3V) on thin blades like these?
Click to expand...

Hey Shawn/DBH - Don't push a K390 run at AKS ;) .... maybe I should grab more k390 - heheh.
 
bluntcut said:
Use Bend Allowance Calculator would answer the how far your blade could/would bend. K-factor is around 0.5.

There would be some durability different, depends on range of deflection within elasticity [true, proportionality, limit]. Proportionality start(scatter back/forth plastic movement) and end of K390 is lower/narrower than 3V... or when flex is stress = steel fatigue factor. Having said that, I think (because I hasn't observed blade failure from fatigued yet) flex cycle of mid elastic range for k390 would out last the consumable life time of the blade. If interest and resources allow, make a k390, zwear, 3v fillet knives - fun to have 3 to test long term use (loan whichever knife to a fishing bud). Oh heck, aks has thin aebl and 440c, why not try them too. With good ht (such as Peters), you probably hoard all 5 :)



Hey Shawn/DBH - Don't push a K390 run at AKS ;) .... maybe I should grab more k390 - heheh.
Click to expand...
Hahaha Devin started it. I was hoping to keep it all for me :p
 
For filleting small fishes (less than 4 lbs, e.g. typical bluegill) - I like a 6" blade taper from 0.04" to around 0.02" thick, taper 0.075 to 1/8" width. 7" blade 0.05" taper to 0.03" for filleting fishes 2-10 lbs, taper 0.8 to 1/8" width. Back to your original quest, perhaps consider getting a bar of nsm 3v .035/.041" (*note: it will cost more than dealer pricing), it should works well for a 6" fillet knife.
 
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