Damn! Knife broke

Varga Knives

Varga Knives

Joined
Aug 12, 2006
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Just when I was getting my confidence up, the first knife I sold came back broken. Of course I'm going to make it right but I woild appreciate any help in identifying if I screwed it up or not. The owner was camping in the Adirondacks and using the knife to baton wood for kindling, just for fun because he had an axe. He said he was striking the spine rear of the wood and there may have been knots in it.

The steel is .10" Elmax at 61/62 (Peter's). Thickness of the spine at the break is .035".

The blade now has a slight bend in it toward the tip and also a slight cant. If there are any pertinent points I'm missing just ask away.

He would be very happy if I could regrind the blade which would be easy enough to do but I don't want to give it back if the temper is screwed.

Best I can do on the pictures.


 
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well tome if the balde is bent and canted..that is not from batoning...it was prying..there is no way i could baton to bend a tip, none...but just my veiw...you are doing good making it right but the story in my veiw is not..jeff
 
I would normally agree with you a 100% but I trust him completely. What may have happened is the ads hit a knot and twisted before snapping. Should that have broken it, though?
 
So, he had a knife break under heavy use and the part that broke was 1/32" thick? Regrind it and call it good enough. If that wood was full of knots it could have been like hitting soft concrete. I doubt very much that Peter's HT messed up the temper, but it is possible. Extremely unlikely, but possible.
 
The grain structure looks iffy to me. In hand it may look different but in the picture it does not look like a refined grain structure.


Fred
 
rc4u12 said:
well tome if the balde is bent and canted..that is not from batoning...it was prying..there is no way i could baton to bend a tip, none...but just my veiw...you are doing good making it right but the story in my veiw is not..jeff
Click to expand...

I can think of at least a couple of ways to break a tip from batoning: the most obvious being if he hit the tip with his baton. 2nd could be from the tip following a knot, or an irregular grain.

At any rate, I don't see this as a failure of the knife as much as a failure of common sense and proper tool use. We're not talking about a 1/4" slab of steel with a beefy tip here. The knife was relatively thin to begin with and even thinner at the point. In my opinion, it broke exactly where I would have expected it to, where 90% of knives break: the point. Also remember, it's a low 60's Rockwell, not mid or low 50's. Elmax is a tough steel, but it's not going to have a lot of spring or flex at that hardness.

As a maker, I would consider this abuse of the knife.

That said, you should be able to re-profile a tip (or even put a nice clip in the blade) and send it back. I do not believe there was anything wrong with the heat treat.
 
My involvement with Elmax, M390, and now AEB-L tell me it is not a steel to use for batoning which to me is just someone trying to destroy a knife. These steels are made for cutting and not for chopping. However, that blade was broken as rc4u12 said. However, is there a possibility that the blade hardness is a little on the low side?
Yes, he is your friend and means you no harm but perhaps his ideas of testing are not made for a knife with the qualities that one had made into it. No, I would not recommend Elmax for a general multi use around camp knife steel. So perhaps if you said you used the wrong steel type for the intended purpose of a general use knife, that might be right. Frank
 
I'm sure it was fine after Perter's got through with it. I am only concerned about overheating in my post HT grinding. I do grind with no gloves but...
 
Your posts beat my last reply.

Fred- could the not so fine grain structure be attributed to overheating post HT

I wouldn't call it abuse on his part. It's good for me to get them in the hands of people who will put them through the ringer. I can learnd a lot that way. I know that he uses the heck out of his knives and I didn't make this specifically for him. He uses Mora's all the time with no issues.

Thanks guys. My only concern is reprofing the knife and giving back one with a questiona grain structure. What exactly happens to hardness if a knife were overheated? I thought it would go softer and so, if anything, it would make it less brittle and more flexible. Would it actually induce larger carbides? Metallurgy is a struggle with me.
 
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This is an interesting scenario. Difficult to troubleshoot though because there are a lot of unknowns. I know you trust the buyer but it does sound odd to me that the blade is bent. I bet you would have difficulty replicating that if you tried battoning it through a steel jig designed to break the tip and bend the blade. Could have bent the blade doing something else first or he could have hammered in a tree and used it as a step. Either way its just speculation.

To quote Spock "Eliminate the impossible and whatever is left, no matter how unlikely, must be the truth." :D

My thoughts on what happened:

1) Bad heat treat; I know its Peter's, but unless he is a one man operation the guy treating your knife that day could have been in a nasty divorce and found out he lost the house, kids and dog to his exwife that day and just made up the RC # after a bad quench or temper or anything else and has since been fired. No business is perfect all the time ask anyone who has run a business!

2) Guy was using it as a stair step or torture testing it to impress friends regarding how tough his custom made knife is, maybe this was the fourth or fifth time and it finally gave. I have a hard time believing it was bent and the tip broke off at the same time. Perhaps he was prying something previously and weakened it at the tip and then hit a knot and broke it.

3) Everything was perfect and he broke it battonning a log. In this scenario I would think about increasing the thickness of your bushcraft line to 1/8" or something.

Either way I think fixing it or replacing it will go a long way to tell potential buyers what type of businessman you are and what they get when one purchases a knife from you. I think you are making the right moves and may never know what caused the actual failure. In the end this is just my opinion and I am no expert so please take it as such!

-Augustus
 
I would agree - overheating from grinding after HT. It takes very little to overheat from grinding !! I've had this discussion a good number of times here and other forums. Witnessed it in a number of good brand knives I have owned . Grinding creates heat no matter how careful you are .Less than optimal methods creates much more heat .Where can it go ? Grindin g with lots of coolant is better but it's not really enough. You should be grinding almost to final dimensions then do the final by hand.
So make a new one and give that owner some lessons in how to use a knife properly !! Batonning should only be splitting with the grain and that done rarely A properly HT'd blade can still be broken !!!
 
You would know for sure if you had the slightest impact on the HT.

A slight discoloration will have no effect with steels like Elmax. Even bluing the tip isn't that big of a deal, and you really have to go crazy to do that. The tempering temperatures of these steels are high.

When you overheat the HT you make the steel softer or tougher, not more brittle or weaker.

Changing the grain structure isn't remotely possible.

It's not reasonable to baton Elmax that hard or that thin.

I think the problem is neither of you knew that.

JMHO
 
I have seen blades bend with the grain while batoning but they always spring back true. Isn't it odd that this blade remained bent?
 
He abused that knife...plain and simple.

Since you have the knife...do some of your own batoning with it and see how it performs.
 
It's abuse and should be something that the customer takes responsibility for. Selling bushcraft or outdoor knives it should be stated that batoning is not covered. It's good of you to repair it though. I would do the same if I were in your position.

Batoning in general is pretty widely recognized by the community (of knife buyers and users) as abuse or at least up to the end users discretion as to whether or not they want to chance being responsible for a broken knife.
 
Please post more pictures of the bend and the cant so we can make a better, more informed opinion.

First off why use the thinnest, pointiest part of the blade to baton kindling? Why not use the area closer to the center of the blade? Don't you usually baton straight down and not at angles?

Second, if you changed the temper of the blade while grinding, say you turned the tip blue, this would spring temper the blade and cause it to bend and not break.

Third, use the right tool for the job, he had an axe but decided to use his custom knife?

I would call this a case of abuse. If he had been using it for fun as a throwing knife and broke off the tip would you be so willing to fix it?

Think about the amount of force that he would have to have been exerting to bend and cant the blade.

Where is the broken tip piece? Did he send that back too and if not why?
 
I don't make a lot of bushcraft knives, but everyone who asks for one wants a very sturdy knife with a beefy point so that doesn't happen.
Like most of the folks on this forum, I'd rather make a fine, thin knife that cuts really well, and use an ax for axing.
Doesn't it seem like we spend half our time educating people on what knives are and how they should be used? I must like doing that....
Incidentally, a fine flat ground knife has got to be the WORST tool for splitting wood. A Scandi grind on a thick blade is several times as efficient.
 
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Thanks guys! Obviously whatever happened was beyond this thin guys abilities and a Mora is generally the same thickness but the Scandi grind keeps the .098" all the until near the tip. Better choice. I don't mind though as I still learned a lot from it. I've made some others with the .098" Elmax but won't thin the tip out this much in the future.

I've never got it hot enough to turn blue but I can't say for certain that I never got it hot enough to smart a little. Thin heats quick!
 
Battoning behind the wood on the spine doesn't really make sense.

I'm thinking he was battoning on the tip, and doesn't want to admit it. He probably knows better(it's obvious you don't beat on a tip that thin or even baton with a knife like that in general) and is embarrassed. You both learned a lesson. I'd advise you to come up with a disclaimer for your thin knives like that.
 
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