A Flaw in the Heat Treat? Or something else?

[effer]

Here is my thread where I was checking the edge of my Bravo 1:
http://www.bladeforums.com/forums/showthread.php?t=775806

Here is a picture of the edge profile:

As you can see the edge is quite thin and angle is very low. How good or how bad that is depends on what you want from the knife and how you use it. My Bravo 1 glides through wood because of this thin edge and low angle, I did some batoning with it and it was fine, but I definitely try to avoid pushing it through big knots, if I don't have to. It takes 5 seconds picking up a different piece of wood, instead of pushing it, damaging the edge and spending 30 minutes fixing the damage. And this is 0.215 Bravo 1. I would imagine the edge on 0.156 Fiddleback can be even thinner.

Damaging such edge while batoning isn't very hard and also depends on type of wood, conditions and technique. But I must agree, that kind of damage during wood carving is a bit odd.

Some people like low angles some people don't.
I've read about a guy putting 20 degree edge on Busse. After some use edge looked like crap too.


I'm very interested to know if this issue with Fiddleback is due to edge geometry or heat treat. Edge geometry is easy enough to adjust to your own liking. It's much easier to go from 20 degree edge to 45, than the other way around. Heat treat on the other hand would be a manufacturing flaw.

 

[penetrator]

I've seen this before as well, on my Ratweiler in SR101 steel. I had a convex edge put on it that was too thin.

The fact that it bent and didn't chip out is a sign of a good heat treat...

There's of course a difference between a factory convex edge, which is (should be) stronger than a flat/secondary bevel, and turning a secondary bevel into a convex which will definitely make the blade thinner and weaker.

What's interesting is that the steel seems to be both weak and brittle (both in the DT video and from reports of users). Rolling edges and brittle fractures, that's probably the worst way that a blade can behave.

 

[SouthernCross]

G'day Falcor

.....The sad part is that most people outside the knife forums don't know that the Fiddleback Recluse is not being made by Fiddleback...

If your suggesting that people are not made aware that the production Recluse is not made by Fiddleback, then you are mistaken.

Since the production Recluse is a KSF exclusive, have you bothered to read the webpage at KSF that lists the Recluse?

If you had, you would surely have seen the following..

"The knife is available in either this custom version built by Andy, himself, or in a production version that is built by Bark River for us."

Seems pretty clear to me



Kind regards
Mick

 

[gerberbmf]

G'day Falcor


If your suggesting that people are not made aware that the production Recluse is not made by Fiddleback, then you are mistaken.

Since the production Recluse is a KSF exclusive, have you bothered to read the webpage at KSF that lists the Recluse?

If you had, you would surely have seen the following..

"The knife is available in either this custom version built by Andy, himself, or in a production version that is built by Bark River for us."

Seems pretty clear to me



Kind regards
Mick

And to me!

 

[NothingCoherent]

Is that all he said! What did he say about the knife? Is he going to fix or replace it?

No, he did tell me to send it in as it is under warranty. But that's it. I didn't even tell him what was wrong with the knife, as all the information is in this thread that I linked (which he refused to read). I was just told to send it in. Then what? I'd like to know what will happen to my knife to "fix" this, before I send it anywhere. If BRKT grinds more steel off to fix the shape, it will just mean an even thinner edge. I tried to message him back, but the forum isn't working properly right now. I'll try again later.

Mike is a good guy, from what I understand. I expect this to be taken care of, but I just wish communication was a little bit better.

 

[SouthernCross]

....Cause Moras also have thin edges, but I've never read or heard of such an edge failure. It chips sometimes, rolls a bit, but it holds its shape, and that's the least we can ask from A2 which have 1%C, 5%Cr, 1%Mo, and some Va, while Moras are just plain 12C27 or 1095.....

I guess I'm a little confused with this one

A Mora can chip sometimes, rolls a bit, but holds its shape?

How is this possible when both chipping & rolling is a change in the shape of the edge?

Try using a Mora with a zero ground scandi edge on seasoned, twisted grain and knotty Aussie hardwood & you'll see edge failure a lot worse than this




Kind regards
Mick

 

[SouthernCross]

G'day Effer

Here is my thread where I was checking the edge of my Bravo 1:
http://www.bladeforums.com/forums/showthread.php?t=775806

Here is a picture of the edge profile:

.....

I assume you are aware that the Bravo1 comes with a convex grind, not the V grind as shown in your picture :thumbup:



Kind regards
Mick

 

[effer]

G'day Effer

I assume you are aware that the Bravo1 comes with a convex grind, not the V grind as shown in your picture :thumbup:

Kind regards
Mick

If you look at the angle measurements at 1/16" steps you will see that it is changing. That's the slight curve of convex grind.

 

[NothingCoherent]

Someone mentioned the Bravo-1 destruction test containing similar damage. I just thought I'd link it here because I went and watched it and this is EXACTLY what happened to my Fiddleback: http://www.youtube.com/watch?v=q-LGwUw5ASE#t=5m50s

Only difference is mine got that way from carving wood...

Just thought this is interesting.

Edit: Look at this!! http://www.youtube.com/watch?v=GjTfudxG01o

My opinion of BRKT is rapidly changing... It's too bad, I love their designs

 

[effer]

......
If BRKT grinds more steel off to fix the shape, it will just mean an even thinner edge.....

I think it's quite the opposite. It's much easier for them to grind off the damage on the edge at higher angle, making the edge thicker.

 

[Madnumforce]

I guess I'm a little confused with this one

A Mora can chip sometimes, rolls a bit, but holds its shape?

How is this possible when both chipping & rolling is a change in the shape of the edge?

Try using a Mora with a zero ground scandi edge on seasoned, twisted grain and knotty Aussie hardwood & you'll see edge failure a lot worse than this




Kind regards
Mick

Well, living in France, the hardest wood I can commonly have is seasonned oak. I tried my Clipper and the 2000 on it, and was very disappointed by the 2000, it got relatively important chips in the edge, but the Clipper holded better, though I had to sharpen it. Chipping and rolling, when it stays reasonnably small, is like an accelerated wear, and sharpening fixes the problem. It may take time, but it fixes. This kind of edge waving NothingCoherent show us is not at all the same kind of damage: it's not supposed to happen, and you have no way to fix it back to normal without insanely grinding it.

I really wonder what's the cause. Sure the edge is thin, but it's not a problem, as it's sold so, and many people used it without problem. Damn, A2 is supposed to be a tool steel, and should have high Young's modulus and yield strenght, it shouldn't deform just as if it was iron (I'm exagerating, but this edge is behaving like a sort of hard iron, not like hardened steel).

 

[NothingCoherent]

I think it's quite the opposite. It's much easier for them to grind off the damage on the edge at higher angle, making the edge thicker.

The damage is too far into the blade for that to work. I'd be losing a few solid millimeters of blade width if they ground it at a steeper angle. I think, anyway. I'm no knife maker! I just can't imagine it working considering how far back the bend is.

 

[effer]

The damage is too far into the blade for that to work. I'd be losing a few solid millimeters of blade width if they ground it at a steeper angle. I think, anyway. I'm no knife maker! I just can't imagine it working considering how far back the bend is.

I'm not a knife maker either, but I'm pretty sure you'll loose a millimeter. That's the only fix that makes sense. If they grind it at lower angle, then the edge will be even weaker and instead of fixing it they are making the edge weaker not only at that spot, but along the whole blade.
If they grid it at higher angle, blade will loose 1 mil of blade width, but gain more robust edge.

You don't necessarily need to loose all the length of the damage. For example in the picture below, if 2/16" is badly damaged (blue color), they can grid more on one side and end up with green profile loosing only 1/16".

In your case, you might end up loosing even less than that.

 

[SouthernCross]

Someone mentioned the Bravo-1 destruction test containing similar damage. I just thought I'd link it here because I went and watched it and this is EXACTLY what happened to my Fiddleback: http://www.youtube.com/watch?v=q-LGwUw5ASE#t=5m50s

I had a close look at the video.

After the strike with the batton at 5:14 (and whilst the edge is engaged with the knott), he adjusts the handle slightly to the side before striking it again. IMO this has set up the lateral stress on the edge which has caused the buckling.

Is this a fault of the knife or a fault with the batoning technique?

There is no doubt that a thicker edge would have probably prevented the damage shown in the video, but then again, better technique with the batton by the tested would have also prevented it




Kind regards
Mick

 

[Falcor]

G'day Falcor


If your suggesting that people are not made aware that the production Recluse is not made by Fiddleback, then you are mistaken.

Since the production Recluse is a KSF exclusive, have you bothered to read the webpage at KSF that lists the Recluse?

If you had, you would surely have seen the following..

"The knife is available in either this custom version built by Andy, himself, or in a production version that is built by Bark River for us."

Seems pretty clear to me



Kind regards
Mick

Good Morning Southern Cross,

Thanks for pointing that out - noted.

Also made me realize where the pressure to censor and close down threads containing any negative comments re BRKT may come from because as a gold member I don't see the adverts..

Cheers

 

[NothingCoherent]

I just spoke with Mike Stewart again, and he explained to me that they cut a piece of the edge off and regrind it thicker to fix this sort of problem. If he's unhappy with the finish, the knife will be replaced.

Definitely good customer service over at BRKT! But I'm still concerned about the actual strength of their blades. I know I'll be babying this knife once I get it back.

Edit: effer's above post appears to be exactly what they're going to do! Good stuff, man.

 

[SouthernCross]

....Definitely good customer service over at BRKT! But I'm still concerned about the actual strength of their blades. I know I'll be babying this knife once I get it back.....

I don't know about babying it.

If the problem is simply an edge that was set too fine, then the regrind offered should fix the problem.

I would use it normally. That way you'll know whether or not it was a fine edge or poor heat treat.

Please let us know how the knife performs when you get it back :thumbup:



Kind regards
Mick

 

[Raining]

Yeah, don't baby it. Use it hard so you know what it can do.

If that happened to one of my blades, I would just sharpen it out at a steeper angle and have a go at the wood again. If worse problems come up, then I'd send it back for replacement.

 

[Neo]

No, he did tell me to send it in as it is under warranty. But that's it. I didn't even tell him what was wrong with the knife, as all the information is in this thread that I linked (which he refused to read). I was just told to send it in. Then what? I'd like to know what will happen to my knife to "fix" this, before I send it anywhere. If BRKT grinds more steel off to fix the shape, it will just mean an even thinner edge. I tried to message him back, but the forum isn't working properly right now. I'll try again later.

Mike is a good guy, from what I understand. I expect this to be taken care of, but I just wish communication was a little bit better.

I don't understand why it's so difficult to explain the problem to him in a mail rather than direct him to a competitive forum he never visits.
(He probably even hasn't a user on this forum)

It doesn't look very nice if you contact him with: I have a problem with a knife you made see the details in the thread I started on a public forum.

Good communication comes from two sides.

Send an email, explain the problem, ask what could have caused it and what he's going to do to fix it, and I'm sure you will get all the answers.

edit
Should have red all post before writing down a comment

 

[me2]

I really wonder what's the cause. Sure the edge is thin, but it's not a problem, as it's sold so, and many people used it without problem. Damn, A2 is supposed to be a tool steel, and should have high Young's modulus and yield strenght, it shouldn't deform just as if it was iron (I'm exagerating, but this edge is behaving like a sort of hard iron, not like hardened steel).

Young's modulus is basically constant for steels. Yes, it is a very high number, but changing steels doesn't change the YM.