Knifemagnets hurt knifes.

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HappyamateurDK

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Hallo.

Looking on the internet for ways to store knifes, I have come across people claiming that knife magnets will have a harmful effect on the steel in knifes. Something about rearranging the molecules in the steel. It does sound like a urban myth to me.

But what do people say.. are there anything truth about it or is it just plane nonsense ?

Thanks.
Søren
 

ian

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Hallo.

Looking on the internet for ways to store knifes, I have come across people claiming that knife magnets will have a harmful effect on the steel in knifes. Something about rearranging the molecules in the steel. It does sound like a urban myth to me.

But what do people say.. are there anything truth about it or is it just plane nonsense ?

Thanks.
Søren

Sounds like nonsense to me. Maybe there’s some effect on the steel, but people have been storing their knives like this for years without it having a noticeable effect.

My only word of caution is that if the magnet is too strong, the motion of taking the blade on and off the strip can cause bending (near the tip) in some san mai knives if you’re not very careful with your mechanics. However, if they bend you can then bend them back easily by hand. I noticed this in my kitchen before I put an extra strip of leather over my mag strip, thus decreasing the strength a bit.

Mag strips are great though.
 
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dwalker

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Hallo.

Looking on the internet for ways to store knifes, I have come across people claiming that knife magnets will have a harmful effect on the steel in knifes. Something about rearranging the molecules in the steel. It does sound like a urban myth to me.

But what do people say.. are there anything truth about it or is it just plane nonsense ?

Thanks.
Søren
The only harm I've ever seen from knife magnets are the scratches you get from using those cheap metal magnet bars. I think the molecules are stable enough in a piece of cold steel.
 

Michi

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Hallo.

Looking on the internet for ways to store knifes, I have come across people claiming that knife magnets will have a harmful effect on the steel in knifes. Something about rearranging the molecules in the steel. It does sound like a urban myth to me.
Complete and utter hogwash. Just think about what would happen if this were true, for example, in electric motors, transformers, or anything else that involves iron and magnetic fields. Magnets are incredibly weak compared to the forces that fix atoms and molecules in a crystal matrix.

Even the world's strongest magnetic field would not affect the steel one iota (other than magnetising it, which does not affect sharpness or other physical properties in any way).
 

Barclid

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Complete and utter hogwash. Just think about what would happen if this were true, for example, in electric motors, transformers, or anything else that involves iron and magnetic fields. Magnets are incredibly weak compared to the forces that fix atoms and molecules in a crystal matrix.

Even the world's strongest magnetic field would not affect the steel one iota (other than magnetising it, which does not affect sharpness or other physical properties in any way).
Magnetization can be annoying from a sharpening perspective, resulting it extra particle bombardment on the edge from metal filings collecting and staying on the edge. Pretty simple to demagnetize the knives if it becomes a problem though.
 
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It has to do with powerful strips, you know the kind that slap a knife on. When you have a thin edge of high carbon steel, the smacking of the edge constantly on that strip will eventually cause stress. This will lead to chipping or small cracks.
 

Bensbites

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I call BS. Sounds like advice that originated from someone selling non magnetic knife storage.
 
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I got a sad picture for later. I was pulling a heavy bone cleaver off of my magnet rack and wacked the edge of the shi.han sitting next to it. But under general use, if you're careful, I've been using magnet racks in pro kitchens and at home for many many years without issues.
 

ian

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I got a sad picture for later. I was pulling a heavy bone cleaver off of my magnet rack and wacked the edge of the shi.han sitting next to it. But under general use, if you're careful, I've been using magnet racks in pro kitchens and at home for many many years without issues.

We need one of those “heart” buttons in addition to a like button, for sad moments like these. Given that the like button was implemented with little controversy, there should be no problem with this, right?
 

icanhaschzbrgr

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It has to do with powerful strips, you know the kind that slap a knife on. When you have a thin edge of high carbon steel, the smacking of the edge constantly on that strip will eventually cause stress. This will lead to chipping or small cracks.
This.

In our hardware shops one can find a cheap 10$ Chinese magnetic knife holders. Similar to this one
Magnetic-Knife-Holders-Safe-and-Powerful-Magnet-Holder-Made-of-Rubber-Magnet-Used-in-Kitchen.jpg

Magnets are surrounded by poorly polished metal strips. They WILL scratch your blades. If you just pull knife — it will be scratched. Edge may also receive damage if you unlucky. Such holders requires their owners to learn a twisting motion (edge to spine) for taking knife off without scratches/damage.

Below is the picture of Nakiri that was damaged thanks to inaccurate usage of magnetic racks. Exactly what osakajoe was talking about.

2018-05-27 17.17.51.jpg

Magnetic racks can be harmful :-\
 

krx927

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This.

In our hardware shops one can find a cheap 10$ Chinese magnetic knife holders. Similar to this one
Magnetic-Knife-Holders-Safe-and-Powerful-Magnet-Holder-Made-of-Rubber-Magnet-Used-in-Kitchen.jpg

Magnets are surrounded by poorly polished metal strips. They WILL scratch your blades. If you just pull knife — it will be scratched. Edge may also receive damage if you unlucky. Such holders requires their owners to learn a twisting motion (edge to spine) for taking knife off without scratches/damage.

Below is the picture of Nakiri that was damaged thanks to inaccurate usage of magnetic racks. Exactly what osakajoe was talking about.

View attachment 58013

Magnetic racks can be harmful :-\

Easy solution for this problem. Just put some tape on the holder. It will prevent scratches. And if the magnets are too strong just add layers until the force suits you. I did this with my cheap ikea holders.
 

Carl Kotte

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Ok, so - in light of all comments - it seems reasonable to say ’yes, some magnet racks have (in conjunction with knife user) led to knife damage’ and ’no, it has nothing to do with any rearrangement of molecules due to magnetism’ (which was the original, now debunked, explanation rightly questioned by the OP).
But the fact that magnet racks can cause damage doesn’t seem to have a lot to do with the magnet racks themselves - unless they are bad (as mentioned in previous posts). If the magnetic pull is strong and the surface of the rack is uneven it may cause damage, but that is no surprise! Just compare: If I accidentally bang the side of my knife blade into my kitchen sink the knife might chip too! But we wouldn’t say that sinks are prone knife damage (or that storing knives on kitchen sinks is a bad idea; at least not for the reason just given). Further - and this happens to me a lot because I tend to overcrowd my rack - if I clumsily hang one knife on the rack and hit the edge of another knife while doing so, the eventual chip or damage doesn’t have much to do with the rack either (although it is true that a knife was chipped when I placed it on the rack).
 
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ian

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Ok, so - in light of all comments - it seems reasonable to say ’yes, some magnet racks have (in conjunction with knife user) led to knife damage’ and ’no, it has nothing to do with any rearrangement of molecules due to magnetism’ (which was the original, now debunked, explanation rightly questioned by the OP).
But the fact that magnet racks can cause damage doesn’t seem to have a lot to do with the magnet racks themselves - unless they are bad (as mentioned in previous posts). If the magnetic pull is strong and the surface of the rack is uneven it may cause damage, but that is no surprise! Just compare: If I accidentally bang the side of my knife blade into my kitchen sink the knife might chip too! But we wouldn’t say that sinks are prone knife damage (or that storing knives on kitchen sinks is a bad idea; at least not for the reason just given). Further - and this happens to me a lot because I tend to overcrowd my rack - if I clumsily hang one knife on the rack and hit the edge of another knife while doing so, the eventual chip or damage doesn’t have much to do with the rack either (although it is true that a knife was chipped when I placed it on the rack).

The bending issue I mentioned doesn’t quite fit with this, but otherwise I agree!
 

Carl Kotte

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On a side-note, am I imagining things or is it truly the case that some knives (say some carbons) attach with more force to the rack (as if the pull were stronger) than others (say some stainless knives)? I sometimes get the impression that my Mazaki and my Misonos are sucked out of my hand onto the rack whereas my cheap Victorinox parings hardly want to stick at all. (And to preempt any misconception, I don’t use drugs - so if I’m way out there drugs have nothing to do with it! [emoji12])
 

CiderBear

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Hmm, I do have to be extra careful to not slam my Wat nakiri against my stainless steel rack. I'm actually thinking about getting a leather covered rack so the landing isn't as bad
 

bahamaroot

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On a side-note, am I imagining things or is it truly the case that some knives (say some carbons) attach with more force to the rack (as if the pull were stronger) than others (say some stainless knives)? I sometimes get the impression that my Mazaki and my Misonos are sucked out of my hand onto the rack whereas my cheap Victorinox parings hardly want to stick at all. (And to preempt any misconception, I don’t use drugs - so if I’m way out there drugs have nothing to do with it! [emoji12])
It's not your imagination. Full carbon and iron clad knives are more magnetic than most full stainless knives. It is the high nickel content of stainless steel that makes it less or even non-magnetic.
 
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Ok. It's not as bad as I had convinced myself late last night. But I was pulling a cleaver off of the magnet rack and I wasn't paying attention. I used proper procedure, I grasped the handle and rotated the edge of the cleaver away from the magnet and started to pull the spine off. When I pulled it slid funny due to the upswept spine and my magnet strips are meant for heavy tools so they're powerful. The cleaver slid hard into the edge of the Shi.Han. Not the type of durability test I had in mind. I'm going to ignore it for now. Doesn't make sense to fix it when the rest just got tuned up and hasn't even been used since.

Before shot. You can see that the placement here was probably a bad idea.

IMG_20190729_215210.jpg


And the aftermath

IMG_20190801_182025.jpg

IMG_20190801_182017.jpg


IMG_20190801_181813.jpg
 

gman

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It's not your imagination. Full carbon and iron clad knives are more magnetic than most full stainless knives. It is the high nickel content of stainless steel that makes it less or even non-magnetic.

i thought chromium content determined stainlessness????

but agree that iron clad knives stick much to mag blocks much harder than stainless clad knives do. i've had to be careful with my iron clad single bevels because the combo of the edge being flat and the cladding being magnetic has led to some unplanned hard hits against the block and resulted in chipping. never had a problem with stainless clad double bevels though.
 

WildBoar

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One way to test for the type of metal on building exteriors is to hold a magnet against the metal. The magnet will not 'stick' to aluminum, of course, but it also will not stick to the stainless steel alloys that are typically used in those applications. If the metal is galvanized steel the magnet will bond to it like a mo' fo'.
 

bahamaroot

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i thought chromium content determined stainlessness????...
It does but Nickel is a big part of stainless steel also. The higher grades or higher stain resistant stainless steels have higher levels of Nickel. e.g. 300 series of stainless has more Nickel than 400 series stainless. 400 series is magnetic, 300 series is not.
 

gman

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It does but Nickel is a big part of stainless steel also. The higher grades or higher stain resistant stainless steels have higher levels of Nickel. e.g. 300 series of stainless has more Nickel than 400 series stainless. 400 series is magnetic, 300 series is not.

interesting. thanks.
 
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