-
The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details: https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is$300$250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
another bark river grasso bolo 2 fail
- Thread starter Polamalu
- Start date
- Status
I'm Filipino/Samoan and I know what a bolo is. A bolo machete would do as you describe but a bolo shaped chopper that thick shouldnt fail like that
Actually, it's not that uncommon. When the blade hits that grain change in very hard wood, the cutting part of the edge is pushed laterally while the rest of the blade is still moving forward, resisting that change. With all the weight of the steel and the speed of the swing as added leverage, you get that half-moon chip.
That's a 5160 your talking about. Bill Siegles 5160 wouldn't do that. Btw did u see the Bk9 destroy the other knot with ease?
Any steel with that geometry can fail like that. My HI khukri suffered a mild half-moon bend -- which is very similar to what happened to your BR -- from similar chopping.
The other knot was quite a bit different, so it's not clear how much less lateral force it put on the steel. Chopping into wood like that creates so many uncontrolled variables that comparisons are difficult.
- Joined
- Mar 8, 2008
- Messages
- 25,913
This is sarcasm, right? Just checking 'cause I've chopped frozen heavily knotted hardwoods and dead pine full of fatwood in the middle of winter with a stainless machete (Condor Viking) in 3/32" stock with a thin edge and never had an edge chip out.
Regardless of how it's happening, I think it's fairly obvious that it's a case of either the blade being ground too thin, the HT being too hard, or a combination of the two. It's not unreasonable to expect a chopper to be able to withstand the kind of use shown in the video. The failure in that other thread was maybe more potentially debatable, but not this one I don't think.
Edit: Oddly, though, it looks like he doesn't even really hit the meat of the knot and there's a cut in the footage right before he shows the blade...huh.
- Joined
- Aug 31, 2009
- Messages
- 2,696
wow, there's no way he's not over heating the edges in that video clip... am I wrong?
THIS WA MIKE STEWARTS TAKE ON THE PROBLEM. PRETTY EXPLANATORY....BUT HE SAID TO SEND THE KNIFE AND IT WILL GET "RE-GRIND"......SERIOUSLY????
First - No matter what - the knife is still fully covered under warranty.
Lets step back and look at the situation.
Whenever You have a Half Moon section out of a blade - Any Blade - Any Maker - it is usually not the blade - Not the heat treat or even the kind of Wood You are chopping.
It is what we all call the Unsupported Chopping Phenomenon. This is where the knife bites and either the user or the Wood Being Chopped turns laterally and literally takes a Half Moon out of the blade edge.
We have seen this happen with a large number of Blades by a large number of makers and none of them were heat treat or even edge thickness related.
That half Moon Breakout is always indicative of this happening.
The Grasso Bolos are 5160 and all of them were Heat Treated the same way - in fact they are all heat treated together at One Time.
If there is a Heat Treat Problem - they either all have it or none of them have it. Since we have had a ton of Folks that have tested them I would say we can rule out a Heat Treat Problem.
To Add - Since these are all Hand Ground - They all spark the same way in grinding and if one of them were bad - the person who Ground it would instantly notice a difference in the Spark Trial and point it out. These are all Ground by people - not robots - so any variation in the Way a blade grinds would be caught right away.
More specifically - That knot section was the first Thing Chopped and if You watch Carefully the chopping was - indeed - Wobbly -Causing more lateral stress than the later chopping with any of the knives.
When the Second chopping was done with the GB-II was done - it actually Cut Deeper and Faster than any of the other knives and was not damaged Further. If it was the heat treat - it would have failed and been Damaged Further. - It was not.
Had the Op Chopped with the GB-II further down on the Wood - this most likely never would have happened. You will also notice that as the Chopping Continued the OP became more Comfortable with Chopping and all of his Strokes were more Deliberate as he gained more confidence in what he was doing.
You will also notice the Spark that was Generated on that last set of chopping. Wood Does not make Steel spark. Commercial Lumber can and does have little pieces of Saw Blade in it - Hence the spark. That was NOT what caused the Break out and it did not damage the Blade on that last set of chopping - It usually does not on any knife because the sliver of Saw Blade is too small to damage a blade.
If we actually did Slow Down the Video Frame by Frame would could identify and isolate the instant that the Half Moon broke out of the Blade. I am Confident that the instant where that happened was a Combination of the Wood Moving and the OP's hand giving a lateral wobble. This would have been a 90 degree movement of the Wood combined with a 90 degree wobble in the opposite direction for the split second.
The Initial Chop - on the End of the plank was causing the rest of the plank to lift slightly off the Ground - not where it was being impacted - it was actually causing the rest of the plank to lift into the Direction of the Chop at 90 degrees to the Blade.
The harder knot only made the plank lift or move more - it was not the actual cause of the break out.
A few weeks ago Ethan Becker held a Becker Head Outing in Tennessee and this same Phenomenon Happened on a number of knives from a number of makers - Some were even Custom Knives (Not a Bark River that time).
Jim Nowka was in attendance and when he called me that Monday he started to tell me about it and I stopped him and Finished the Explanation of what he was about to tell me. He was shocked that I knew exactly what had happened on all the Damaged knives - just from his description over the Phone.
That Half Moon Break out is not uncommon and can happen onAny Brand of Knife and actually can be duplicated.
All of You might find it interesting that All - I mean ALL - Bark River Knives are impact tested - by the exact person that Grinds the blade - Right on the line - At the Station that the Blade was Hand Ground by slamming it into a section of very old - very dry 4" X 4" post to check the Terminal Geometry on EVERY knife.
The Bottom Line is that it truly is a Combination of User Error and Lack of Support of the thing being Chopped. It is totally unintentional and not something to point fingers at or about - it just sometime happens.
This is what solid Company Warranties are for.
No matter how it happened it is 100% covered under our Warranty.
I hope I have gone over this in enough detail to make it Clear.
Send the knife in and we will re-grind the blade at no charge.
Mike
BRKCA MIKE #01
NJKCA #041
"I Am America"RIP Chris
First - No matter what - the knife is still fully covered under warranty.
Lets step back and look at the situation.
Whenever You have a Half Moon section out of a blade - Any Blade - Any Maker - it is usually not the blade - Not the heat treat or even the kind of Wood You are chopping.
It is what we all call the Unsupported Chopping Phenomenon. This is where the knife bites and either the user or the Wood Being Chopped turns laterally and literally takes a Half Moon out of the blade edge.
We have seen this happen with a large number of Blades by a large number of makers and none of them were heat treat or even edge thickness related.
That half Moon Breakout is always indicative of this happening.
The Grasso Bolos are 5160 and all of them were Heat Treated the same way - in fact they are all heat treated together at One Time.
If there is a Heat Treat Problem - they either all have it or none of them have it. Since we have had a ton of Folks that have tested them I would say we can rule out a Heat Treat Problem.
To Add - Since these are all Hand Ground - They all spark the same way in grinding and if one of them were bad - the person who Ground it would instantly notice a difference in the Spark Trial and point it out. These are all Ground by people - not robots - so any variation in the Way a blade grinds would be caught right away.
More specifically - That knot section was the first Thing Chopped and if You watch Carefully the chopping was - indeed - Wobbly -Causing more lateral stress than the later chopping with any of the knives.
When the Second chopping was done with the GB-II was done - it actually Cut Deeper and Faster than any of the other knives and was not damaged Further. If it was the heat treat - it would have failed and been Damaged Further. - It was not.
Had the Op Chopped with the GB-II further down on the Wood - this most likely never would have happened. You will also notice that as the Chopping Continued the OP became more Comfortable with Chopping and all of his Strokes were more Deliberate as he gained more confidence in what he was doing.
You will also notice the Spark that was Generated on that last set of chopping. Wood Does not make Steel spark. Commercial Lumber can and does have little pieces of Saw Blade in it - Hence the spark. That was NOT what caused the Break out and it did not damage the Blade on that last set of chopping - It usually does not on any knife because the sliver of Saw Blade is too small to damage a blade.
If we actually did Slow Down the Video Frame by Frame would could identify and isolate the instant that the Half Moon broke out of the Blade. I am Confident that the instant where that happened was a Combination of the Wood Moving and the OP's hand giving a lateral wobble. This would have been a 90 degree movement of the Wood combined with a 90 degree wobble in the opposite direction for the split second.
The Initial Chop - on the End of the plank was causing the rest of the plank to lift slightly off the Ground - not where it was being impacted - it was actually causing the rest of the plank to lift into the Direction of the Chop at 90 degrees to the Blade.
The harder knot only made the plank lift or move more - it was not the actual cause of the break out.
A few weeks ago Ethan Becker held a Becker Head Outing in Tennessee and this same Phenomenon Happened on a number of knives from a number of makers - Some were even Custom Knives (Not a Bark River that time).
Jim Nowka was in attendance and when he called me that Monday he started to tell me about it and I stopped him and Finished the Explanation of what he was about to tell me. He was shocked that I knew exactly what had happened on all the Damaged knives - just from his description over the Phone.
That Half Moon Break out is not uncommon and can happen onAny Brand of Knife and actually can be duplicated.
All of You might find it interesting that All - I mean ALL - Bark River Knives are impact tested - by the exact person that Grinds the blade - Right on the line - At the Station that the Blade was Hand Ground by slamming it into a section of very old - very dry 4" X 4" post to check the Terminal Geometry on EVERY knife.
The Bottom Line is that it truly is a Combination of User Error and Lack of Support of the thing being Chopped. It is totally unintentional and not something to point fingers at or about - it just sometime happens.
This is what solid Company Warranties are for.
No matter how it happened it is 100% covered under our Warranty.
I hope I have gone over this in enough detail to make it Clear.
Send the knife in and we will re-grind the blade at no charge.
Mike
BRKCA MIKE #01
NJKCA #041
"I Am America"RIP Chris
Busse would have replaced that! how are you going to re-grind a bad temper knife? also it wont have any belly....that's pathetic
stabman
Gold Member
- Joined
- Sep 17, 2007
- Messages
- 21,322
The lack of belly could be annoying, but it looks like that's how it's done.
Busse is a different company, and their warranty is different.
The edge will be the part affected by over-grinding; the rest of the steel will be fine. Hence, grinding away the affected steel corrects that issue (as long as it is not over-heated by the regrind).
They will likely grind a more obtuse angle than there was originally, given that they know the type of use the owner intends.
Busse would have replaced that! how are you going to re-grind a bad temper knife? also it wont have any belly....that's pathetic
as far as i know the knife isn't deferentially heat treated. so i would assume if the whole blade is compromised. a bolo isn't a bolo without its belly
stabman
Gold Member
- Joined
- Sep 17, 2007
- Messages
- 21,322
They grind the blade after heat treating.
This means that the thinnest part of the blade--the edge--is susceptible to being over-heated during the grinding process.
This can affect...the edge.
The rest of steel stays fine, as it's of a thickness enough to NOT be affected by the overheating of the edge.
It has nothing to do with differential hardening or anything of that sort.
from what i know as long as you do go over 400 degrees you wont ruin the heat treat. from time to time their knives HT get ruined.
can any of of the knife makers here concur from this comment
IMO they need to improve their manufacturing process
+1
An enlightened Forum Member. :thumbup::thumbup:
Big Mike
i guess bark river knives can't handles any type of hard wood even to a small knot. hard woods and baby knots are their kryptonite
I don't know where that comes from?
Is that based on personal experience?
Being you are the OP in this thread,is that you in the video you posted?
If not, what's your stake in this thread?
Big Mike
- Status