Who makes a full convex grind blade?

[Walt2]

The question was asked, what makers use convex grinds. Try Ed Caffrey.

 

[ichor]

Originally posted by UnknownVT
hmmm......

-
do you know I have not found one single point where the face is FLAT against the ruler?
at all points the face is "convex" as I understand the word, ie: there is a curvature against the ruler, and the ruler can be rocked against the face - so it's not flat.

Hmmm.........my relatively new #6 is flat as the provervial pancake, against a ruler.

 

[Gary W. Graley]

Jimmy Fikes, IF you can find any! I've heard tell that he is back into knives again, which is a good thing, I have a craving stirring up for a small chiseledge knife, his are among the sharpest knives I've ever handled. Full convex grind...
Here are some examples of Jimmy's work...enjoy!

G2

 

[Daniel Koster]

Somewhat new #12 - also flat as flat gets (a little handle carving has been done).

 

[UnknownVT]

Originally posted by pendentive
Somewhat new #12 - also flat as flat gets

also

Originally posted by ichor
Hmmm.........my relatively new #6 is flat as the provervial pancake, against a ruler.

Interesting.... thank you gentlemen - I really did not know this.

I had always thought Opinels were all Convex ground with zero bevel edges - in fact that is precisely the only reason I bought any..... so obviously all mine are only very obviously convex ground.

However this is such an intersting question I did some (minimal) net research - using yahoo.com and searching on
+Opinel +flat
although I found pages with both these words the only page that said anything relevant was this:
[Outdoors online magazine] Opinel number 12.
... Opinel Number 12 Folder 28 cm open [2], 12 cm blade [3], thickness 2mm. ... The blade grind is flat V, with a very fine edge, NIB is not the sharpest that can be ...
outdoors.free.fr/s_article.php?id_article=6 cached

Searching on
+Opinel +convex
gave these:
Dark Matter: Knives: Opinel
Opinel knives are inexpensive wooden handled French twistlock folders. I like them, because the carbon steel blade is convex ground with no bevel, so they cut ...
www.canit.se/~griffon/knives/misc/opinel.html cached

CATALOG - Keywords
... Opinel knives still feature the same convex edge profile as a century ago. This shape gives more keenness and strength. It is easy to sharpen. ...
www.worldscoutshop.org/php/catalogue/mc.php?langue=en&idmc=38 cached


I also did a search here on BladeForums.com for
Opinel convex
and got quite a few posts that say Opinels were convex gound.

However doing a search on BladeForums.com for
Opinel flat
also finds several posts that say Opinels are flat ground.

I do NOT doubt that the blades of the quotes at the top of this post are flat - as it is simple to check against a ruler.

However I know my 3 ready to hand No.8's are all unmistakably convex ground - and obviously I've seen enough that I thought all Opinels were convex ground.......

But just as obviously I was mistaken in this latter assumption -

so what's the word on this?

Opinels obviously vary - is it -

by size? a #6 and #12 are flat, yet my #8's are convex -
doesn't seem to make sense.

by when they were made? perhaps Opinel have reverted to a flat grind for more recent knives? I had thought Opinel built their reputation on the convex blades........

by who made them? manufacturing tolerances are that wide? Cliff Stamp reported that he's seen recent ones with slight convex on one side and flat on the other(!) as well as secondary bevels(!)

This is so perplexing (to me ) that I've started another thread about this:

Opinels - Convex or Flat grind?

Thanks guys......

 

[Greg Covington]

Originally posted by made2cut
I think Greg Covington (xrayed ?) does convex grinds.

Yep...still do them but I have been more into flat grinding lately....and some that are a combo of the two.

 

[J M Stewart]

Bark River Knife and Tool does indeed make fully convex ground blades. Here are two examples: The GlenEagle Axe and the Fieldsman. The cool thing about the GlenEagle is that it serves a dual purpose; a handy hatchet, as well as an ulu-type tool.

All of the models, however, are fully convexed.

Jason

 

[JDMSMBACPA]

has anyone done a review on the Bark River knives? They look good on paper:

• Laser cut from solid A-2 Tool Steel
• Double quenched for maximum grain growth
• Triple tempered for maximum grain refinement
• Cryo-treated for maximum stress relief
• Convex ground to sharp for hair splitting edge
• Ergonomic handle designs for ease of use
• Tangs drawn soft for flexibility
• 100% American-made
• Lifetime guarantee for performance

Unfortunately, I can't find any reviews. I tried a search, but I only found two requests for reviews and two threads that were closed for violating the advertising policy . . .

 

[JDMSMBACPA]

Bark River has a forum over at www.knifeforums.com. The reviews so far look pretty good--especially given the prices and the specs. On the down side, they are back ordered 60 to 90 days. Still, I think I will order a Gameskeeper with green micarta scales:

If I do, I will post a review.

 

[Cliff Stamp]

JDMSMBACPA :

Double quenched for maximum grain growth

I would hope that is a type. Grain growth is to be avoided.

-Cliff

 

[JDMSMBACPA]

Yea, someone asked the owner, Mike Stewart, about that over on the other forums. The long answer was a little too technical for me. If I understood it correctly, I think it meant maximizing the creation of carbides in the steel. The short answer was "Maximum Grain Growth is an oversimplification in terms but the process the way we do it does elliminate any molcular voids and gives a stronger and more uniform blade." LINK

 

[Cliff Stamp]

Thanks for the link. That reply made little sense as growth means the opposite of refinement. Refining the grain is decreasing the size.

Carbide segregation, which is increasing the sise is also not something you would want to do. See for example the CPM process which is designed to do exactly this and promote smaller evenly dispersed carbides.

Nice looking knives though.


-Cliff

 

[JDMSMBACPA]

Well thanks Cliff, your opinion is worth a lot in my book. I really hope it is just poor communication and not poor metalurgy on Bark River's part. I've read Stewart has 20 years of knifemaking experience and was a key figure at Marbles and Blackjack (both knives I like, but I like the Gameskeeper's style better). Maybe I'll wait for more reviews before I drop the $169. I've also got my eye on the similar Micarta handled Fallkniven F1 due out in August and/or their bare blades. The Fallknivens are plenty strong without a full-convex profile.

 

[Cliff Stamp]

Unfortunately Mike would not be explicit about the process as its a "Trade Secret" thus it is hard to debate it fully.
Once the blades get out into the hands of the users and feedback comes in on the merits of the steel vs 52100, which is also commonly used on such knives, it should open the floor for more discussion.

-Cliff