# Straightening out a knife



## rdm magic (Apr 16, 2012)

I recently bought a sab nogent, which when I opened is slightly bent. When on a flat surface the knife doesn't touch all the way down.

I'd rather not have to return the knife because I paid postage, taxes etc on it that I won't get a refund on, and may have to pay again if I were to return it and get a new one.

Are there any fixes for this or not?


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## boar_d_laze (Feb 13, 2008)

There are fixes. They involve a bench vise, knowing what you're doing, and knowing a little about the ins and outs of bending metal at a weak point which has developed "spring memory" over more than half a century.

Pad the vise, clamp the blade so the bend point extends beyond the vise jaws by about a millimeter. It's likely that the bend is at the intersection of tang and blade, right at the ferrule. If so, clamp the knife so that the finger guard is outside the jaws but pressing against them. Use the handle to gently bend the knife, in one direction against the bad bend. Don't bend more than a couple of millimeters at a time, hold the pressure for a minute or two, then release it. Checking your progress frequently, repeat the process until the bad bend disappears. Do not remove the handle or heat the knife. Do not rush the process. Wee, tiny, itsy-bitsy baby steps -- one at a time. Slowly slowly catchee monkey.

_*However*, returning the knife for a straight replacement is a _*MUCH*_ better idea._ Bent Nogents are a known problem, and you should have contacted TBT _before purchasing_ and told them you wanted a straight knife to begin with. Now that you have one, you should contact them (her, actually) again. *Call* (as opposed to e-mailing) The Best Things, explain the problem courteously, and arrange for an exchange if possible.

You should not have to pay tax or customs for a "free" exchange, but you will have to pay shipping. Contact the post office, or customs or whoever sets the duties and/or taxes in wherverthehell you are and find what they'd like from you in order to just pass the knife through without assessing further charges.

Say hello from me to the nice lady at TBT. It may not help, but it won't going to hurt either.

Good luck,

BDL


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## rdm magic (Apr 16, 2012)

Okay, thanks for the advice. I'll probably give the vice a go. In all honesty the bend isn't that bad, I'm just concerned about how it is going to affect the sharpening of the blade in the future, which perhaps you'd be able to help me with. Will it be a big problem, or not really affect it?


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## boar_d_laze (Feb 13, 2008)

It's not a big deal unless the bend isn't on the tang.  If the blade itself is bent, you must replace it.

BDL


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## rdm magic (Apr 16, 2012)

The blade is bent. not the tang. Why must it be returned, could you please explain the long term effects of having a bent blade?

I was planning to try to straighten it out as demonstrated by Mark in


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## dcarch (Jun 28, 2010)

I don't know if you can bend good steel.

The blade will spring back when you bend it, and Just when it almost can be bent, it will crack into two pieces.

dcarch


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## knifesavers (Oct 5, 2011)

rdm magic said:


> The blade is bent. not the tang. Why must it be returned, could you please explain the long term effects of having a bent blade?
> 
> I was planning to try to straighten it out as demonstrated by Mark in


To quote BDL


> _*However*, returning the knife for a straight replacement is a_ *MUCH* _better idea._ Bent Nogents are a known problem, and you should have contacted TBT _before purchasing_ and told them you wanted a straight knife to begin with. Now that you have one, you should contact them (her, actually) again. *Call* (as opposed to e-mailing) The Best Things, explain the problem courteously, and arrange for an exchange if possible.


Sometimes things will bend back and other times not. I have an old Rogers fillet made in japan that does not want to bend back at all and probably will not.

You break it and you are out whatever you spent. If you can exchange it for a straight one just do it.

Jim


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## rdm magic (Apr 16, 2012)

I know what BDL said, but I was curious as to the long term effects of using, and sharpening a bent knife. I explained also why I'm reluctant to return it, I already paid around 25$ postage, which it would be to return it, plus I had to pay tax on arrival and there is every chance that I'd have to pay it again (I know that I shouldn't have to, but try explaining that to customs). 

I wouldn't think that knives are easy to snap; am I wrong?


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## rekonball (Sep 13, 2011)

rdm magic said:


> I recently bought a sab nogent, which when I opened is slightly bent. When on a flat surface the knife doesn't touch all the way down.
> 
> I'd rather not have to return the knife because I paid postage, taxes etc on it that I won't get a refund on, and may have to pay again if I were to return it and get a new one.
> 
> Are there any fixes for this or not?


I had a 12" henckels that had a big dogleg in it and it really bothered me so I sent it back, then they sent it right back to me, of course this was new never used. I don't by henckels anymore, they must of had a crosseyed inspector giving it the ok. Send it back if you can write them a letter telling them what's wrong and hope they aren't cross eyed. I con't know how hard this knife is but I did put it in a vise, it didn't straighten it out totaly but it's better. If you don't or cant and you can live with it I think the only real problem would be sharpening it. Good luck Maybe you could use it as a grapefruit knife.


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## rdm magic (Apr 16, 2012)

Okay, so hopefully someone can answer these questions for me.

What are the long term problems associated with sharpening, and using a knife which isn't straight?
The knife in question is actually barely bent at all, when on a flat surface it veers 2, maybe 3 degrees upwards. Does this affect the problem at all? How about straightening it as Mark does in the video, earlier in this thread?


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## jbroida (Nov 13, 2011)

sharpening with a bend or warp can cause uneven bevels and even holes to develop in the edge as it can be impossible to make contact with the stone in some areas.  It ca also lead to blade shape changes over time and can make the knife difficult to cut with.

Where are you located?  Maybe i can help (when i get back from Japan).


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## rdm magic (Apr 16, 2012)

Ok, so I returned the knife and got a full refund.

Now I'm in the market for a 240mm, or 270mm chefs/gyuto, probably going to go j this time because although I didn't dislike the Sab, I wasn't overly fond of it.

Could I get some recommendations for a gyuto, 270mm, carbon or stainless is irrelevant, pretty good sharpener. As I said, I'm in the UK, so for something from CKtG add about 50$ postage onto the price. I'm not on a strict budget, but I don't want to splurge for no reason either. Bang for your buck is quite a high priority, and something JCK would probably be better due to their postage.


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## just jim (Oct 18, 2007)

I love my 240mm Fujiwara FKM, I'm sure you would be happy with a similar 270.

Got if from JCK.


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## rdm magic (Apr 16, 2012)

Any idea how the Fujiwara compares to the Carbonext?


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## kingofkings (May 1, 2012)

I recently bought a vintage knife off ebay, wasn't all that expensive or anything. When I got it, I sharpened it up and I can see that there is an uneven point on the bevel that I've sharpened, only on one side, around 2/3 of the way up, the bevel is larger. The other side has a perfectly even bevel.

I think that this might be caused by the knife being slightly warped, but I can't see any bend in the knife. Is it because its bent or is there another issue at heart?


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## boar_d_laze (Feb 13, 2008)

The Fujiwara FKM is a good entry-level knife.  It's a very good value, but for good and ill, it's entry-level to the high end. 

CarboNext is a huge value over-achiever.  A lot of owners say that it's a happy exception to the "you get what you pay for" rule; and -- for 20 extra GBP (or so) -- it's at least one full step up from the FKM.  If you're a good sharpener, it takes a great edge and holds it extremely well.  F&F is good.  Handle is okay -- not a Misono or MAC -- but comfortable if you have a good grip.   Profile is good if you're not used to something better, in which case it's merely okay. 

If you buy the CarboNext, don't purchase JCK's extra-cost sharpening. 

BDL


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## boar_d_laze (Feb 13, 2008)

> It's likely to be an overgrind. Quite common with vintage knives who have been sharpened and thinned by guys going through the streets with their cart. If you care you may try thinning to even it out. Soon you will experience if the overgrind is too deep, in which case there is no real long term solution, and the overgrind will eventually end in a hole in your edge. This is not that common, though.


Benuser FYI, this doesn't apply to the Thiers-Issard "Nogents" sold by The Best Things and the subject of this thread. Although the blanks are pre WWII, they were _stored as blanks_ -- without handles or edges. The knives are NOS and were not sharpened nor given their handles until shortly before shipment. T-I factory sharpening is HORRIBLE, but an over-grind is extremely unlikely and the putative history of sharpener/peddlers carting their wheels from street to street is inapplicable.

Bends are not uncommon with the "Nogents" sold by TBT. They are possibly the result of forging, tempering, or heat treatment at the time of manufacture; but more like the result of poor, very long term storage.

BDL


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## kingofkings (May 1, 2012)

boar_d_laze said:


> Benuser FYI, this doesn't apply to the Thiers-Issard "Nogents" sold by The Best Things and the subject of this thread. Although the blanks are pre WWII, they were _stored as blanks_ -- without handles or edges. The knives are NOS and were not sharpened nor given their handles until shortly before shipment. T-I factory sharpening is HORRIBLE, but an over-grind is extremely unlikely and the putative history of sharpener/peddlers carting their wheels from street to street is inapplicable.
> 
> Bends are not uncommon with the "Nogents" sold by TBT. They are possibly the result of forging, tempering, or heat treatment at the time of manufacture; but more like the result of poor, very long term storage.
> 
> BDL


I believe benuser was addressing me.

In the event that it's not a case of overgrind, what else would it be? What are the long term problems with an overgrind?

Do you have any idea how the carbonext (discount the f&f, handle comfort etc, purely talking about edge taking ability and profile) would compare to something like the misono sweden, or kono hd?

I want a new 240mm gyuto, the CN is high on my list, but I'm curious as to how good the knife is compared to something like a Kono or Gesshin.


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## full sack (Oct 19, 2014)

Knife straight.jpg




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full sack


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Apr 24, 2015








Got this Sabatier, yesterday, from Bernal Cutlery - $5.00.

Across the spine, near the tip, had a severe, complex twist, so I left it clamped over night. The edge had only a minor bend and straightened in an hour.


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## jake t buds (May 27, 2013)

Full Sack said:


> Knife straight.jpg
> 
> 
> 
> ...


That's a great idea. I would never put a knife in a vise and push. No control other than your eyeball and your body. Your c-clamps are graduated by the threads. Nice.


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## galley swiller (May 29, 2013)

Maybe two observations here. 

First, I don't think that Full Sack mentioned any pushing in his post.  Ony overnight clamping.

Second, I am observing in the photo that the clamp is coming down onto a flat board, which is between the flat of the blade and the C-clamp tip.  The board is spreading the load over a much larger area of the blade than would happen if there was contact directly between the clamp and the blade.

Full Sack, am I right on this?

GS


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## full sack (Oct 19, 2014)

Galley Swiller said:


> Maybe two observations here.
> 
> First, I don't think that Full Sack mentioned any pushing in his post. Ony overnight clamping.
> 
> ...


I took this slowly. The knife didn't completely straighten, with overnight clamping, so I applied more clamp pressure and waited again, (knives can break during this process). I also experimented, with different shim spacing, of the bottom shims.

With a marker, I marked the center of the bend and placed the shims at equal distances from the mark.

In the picture, the clamp pressure is creating an overcorrection. Applying only enough clamp pressure, to make the blade straight, didn't reduce the twist.


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## jake t buds (May 27, 2013)

Galley Swiller said:


> Maybe two observations here.
> 
> First, I don't think that Full Sack mentioned any pushing in his post. Ony overnight clamping.
> 
> ...


If you read my post carefully, I was making the distinction between what he did and what some other suggestions that were posted here. The c-clamp provided slow measured steps in pressure, as opposed to just pushing a blade held in a clamp until you active the desired effect.


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## rick alan (Nov 15, 2012)

I have straightened soft blades like the Nogent simply by sticking them in a vice and flexing repeatedly, holding for a minute or so each time.  \Have adequate protection between you and the blade, wear eye protection and monitor your balance just in case the blade does snap on you. Clamping like Full Sack has done is a more elegant solution.

Though some here may cringe peening is often employed here in industry, including knife making, using a ball-peen hammer, and even a carbide gouge, and whacking the convex side.  For knives this is not typically employed in the finished stage though, so maybe I shouln't have even brought it up.

Rick


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## rick alan (Nov 15, 2012)

Ooops, in the last sentence that should read "wacking the concave side."  This creates stress that warps the metal in the opposite direction of the bend.

Rick


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