Compass de-magnetizing in hollow handle?

TAH

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I just got a CRK Sable IV and I put a SAS button compass in the aluminum cap.

If I leave the cap screwed on the A-2 handle indefinitely, will the compass become demagnetized if the compass dial is at rest "off the needle"? Obviously, when the knife is laying on its side, the dial is not free to float. So there is no pull on the dial from the A-2. In other words, in order for a compass to become demagnetized by steel, does it have to be free floating and being pulled off course for a long period of time?

Here's the compass...

nato_survival_compass_sm.jpg
 
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AFAIK you won't have any problems. I have never heard of a compass getting demagnetized by steel. If the steel had a magnetic flux to it then it's highly possible. Please correct me if I'm wrong I just don't think it happens.
 

TAH

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AFAIK you won't have any problems. I have never heard of a compass getting demagnetized by steel. If the steel had a magnetic flux to it then it's highly possible. Please correct me if I'm wrong I just don't think it happens.

Same here. I have never heard of this happening first hand, but I have heard "rumors" that it can.

A-2 steel is non-magnetic.

I'm not sure what is considered non-magnetic steel, but a magnet does stick to this knife. Also, if the compass is at rest and you wave the knife by it, the dial does move.
 
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As I understand it, it is moving the steel by the needle rapidly and repeatedly that could demagnetize (degauss) the compass. I don't think having the compass on the knife will affect it. You will want to, if you haven't already, be sure the compass still points North, etc. It's surprising how a little bit of metal will pull the compass off if it's close by it. Steel, like all ferrous metal, will attract a magnet, and can become magnetized in any of several ways. A question, though. With the compass on the handle, will you still be able to drive it into something without breaking the compass? I prefer my knives to have no glass parts, and my compass to stay in my pocket or pinned to my gear.
 
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A-2 is definitely magnetic !!! As is any blade of martensite [hardened steel]. Check to see if the blade has been magnetized as the sometimes use magnetic chucks to hold the blade while making. That MIGHT effect the compass.I have never heard of it though. Those small compasses are not the best !! I suggest you carry a real one ....I was hunting with a group when one of them got confused .We checked his compass and it didn't work .He said that's ok I have another one.We checked that one and it didn't work either !!!
 
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I might be wrong here too, but I think Gollnick is referring to the fact that A-2 steel will not HOLD magnetic flux, yes it is magnetic but it isn't magnetized so easily. That may not be true, but I know that it can be the case.
 

TAH

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With the compass on the handle, will you still be able to drive it into something without breaking the compass?

Other than sticking the knife into a log, I typically don't drive my knives into objects. I don't foresee this being a problem.


Check to see if the blade has been magnetized. Those small compasses are not the best !! I suggest you carry a real one.

The blade has not become magnetized. I agree, small button compasses are generally not the best, but this one is of pretty high quality - currently costing around $35. It is just a back up for my Silva.
 

Gollnick

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A2 shouldn't become magnitized. If the blade does seem to affect the compass, I think one of three things will be true: A) it's not the blade the compass is responding to; it could be, for example, your watch. B) Your blade is not, in fact, A2. C) Something quite powerful happened to your blade.

Most machine shops have a powerful machine which is used to demagnatize tools. A trip through one of those machines (with the compass removed, of course) will solve the problem. Another option is to strike the blade sharply with a hammer. If a pliers, for example, becomes slightly magnetic, which can be very annoying, you can just drop them onto a concrete floor; the sharp impact will demagnatize them. With a blade, you wouldn't want to drop it since you might chip the edge.
 

TAH

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A2 shouldn't become magnitized. If the blade does seem to affect the compass, I think one of three things will be true: A) it's not the blade the compass is responding to; it could be, for example, your watch. B) Your blade is not, in fact, A2. C) Something quite powerful happened to your blade.

A) It was the knife that made the compass dial move. I was not wearing a watch or belt buckle.

B) The Chris Reeve One-Piece Knives are an integral design and definitely made of A-2. A refrigerator magnet does stick to both the blade and handle.

C) I'm not sure of CRK's manufacturing processes, so I guess it is possible that the knife became magnetized somehow during production - that is if A-2 is indeed non-magnetic.

P-CR00634.jpg
 
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I had a problem with my sas compass. It became demagnitized by leaving it my wallet next to my credit cards for months. I needed to relace it with a new one. I doubt that A2 steel is your problem.
 

TAH

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I doubt that A2 steel is your problem.

There is no problem with the compass. It works fine in the aluminum buttcap. However, the A-2 does affect the compass when they are brought together.

Again, I was just wondering if the A-2 could demagnetize the compass over a long period of time.
 
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