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Just a thought......

saxonaxe

saxonaxe

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A gift of a 'Marbles' compass and a Mora Eldris short blade knife revealed ( to me at least ) a quite surprising fact. The Mora is stainless steel and in my experience stainless steel blades normally have a generally low if any effect on a magnetic compass. Not so the Mora !! Although only a couple of inches long and stamped stainless, at a measured distance of 2 inches from the little, reasonable quality, compass it will spin the needle 180 degrees.....At 3 inches it will pull the compass 45 degrees off course every time.

I mention this because I saw a photo of someone wearing an Eldris as a neck knife with a small compass attached to the lanyard...
I suspect it was probably that bloke who keeps writing about getting lost..🤣
 
Very interesting 🤔, never thought about a knife/metal affecting a compass, makes perfect sense tho, but the thought never crossed my mind lol. Also iv never seen any survivalist on YouTube or tv reference this nor have I read about it 🤷🏼‍♂️ Learn something new every day 😂
 
I believe it all depends upon the mix of the metal , stainless being an alloy after all. A lot of stainless knives are magnetic there being a lower percentage of chrome for instance added to it. This allows it to hold an edge but not go rusty. For a lot of my working life i used A2 stainless fixings , bolts , plates or whatever and occasionally A4 marine grade stainless ( used some of that at Birmingham cathedral , well known for being next to the sea) and that definitely isn't magnetic but it is also softer thus not really much use for cutting edges.
Oh and then there's stuff known as chrome steel , at least at the scrap yard which seems even closer to steel than stainless.
 
I suspected it was to do with the metal characteristics Baytree, but had no idea of the true facts. Good info. Thanks. 👍
 
It is known as Martensitic stainless steel, it is also in a lot of Swiss Army knives..... and yes, it is magnetic. It is to do with the ratio of carbon:chromium:nickel that is added to the steel. Some of the Mora knives are also laminated combinations of hard and soft steel.
 
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Very interesting, I'm still learning at nearly 77...😊
I distinctly remember having to buy stainless steel bolts to fix the compass Binnacle in position in the cockpit of a sea going yacht I once fitted out. Marine grade stainless which tested as completely neutral for any magnetic influence on the compass.
 
saxonaxe said:
Very interesting, I'm still learning at nearly 77...😊
I distinctly remember having to buy stainless steel bolts to fix the compass Binnacle in position in the cockpit of a sea going yacht I once fitted out. Marine grade stainless which tested as completely neutral for any magnetic influence on the compass.
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That would be something like 304 grade stainless which has a higher percentage of chromium. It's non magnetic, easier to weld, much tougher and corrosion resistant but not as hard (won't hold a good edge). it is also used in the stainless steel flu liners, cutlery and kitchenware. There are millions of things that I'd rather have more knowledge of but after studying product design with a bias towards manufacturing processes it's what I've got.
 
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If memory serves me i seem to recall that stainless steel was an accidental invention/discovery. Started , i think , as an experiment in a Glasgow shipyard , didn't do what was hoped for with the mix and was put aside where it was noticed some months later not to have rusted and was thus re-examined.
 
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