Has anyone successfully demagnetized a flashlight tailcap magnet using an inexpensive AC demagnetizer? I’m thinking of the type you plug in to AC, push the button, then slowly lift the object you want to demagnetize through and then out of the field.
I know the demagnetizers work on tools like screwdrivers, but I don’t know if they demagnetize the strong magnets in some flashlights.
Thanks in advance.
some magnet material is changeable after being made, other materials are not
i have 2 of those demagnetizers, if you are around atlanta
wle
Unfortunately, I am not near Atlanta. I do appreciate your response to my question. I think I’ll have to buy a demagnetizer to see if it would work. I’ll have to decide if the experiment is worth the cost. I can’t carry flashlights with magnets in them - I’ve got too many key cards in close proximity. It’s inconvenient for me that magnets are becoming so popular on lights.
If you can get contact with the magnet you can kill most of the magnetism by heating it up with a soldering iron or heatgun.
I solder a wire to a magnet, the heat caused the magnet to weaken.
Thanks for the responses - it’s interesting to see your ideas about possible approaches I could take. I’ll think about it - I’d have to be very careful not to ruin the endcap in the process of making contact between the magnet and a very hot object, but I could try it. Maybe I’ll risk it on my Manker E02h.
I’ve completely demagnetized a very strong neodymium magnet by heating up till red hot with a propane torch.
I’ll have to consider the heat approach, but I know it has to be a very high temperature to work. I risk deforming any other part of the flashlight that heats up, so that has to be a caution with this approach. That’s originally the reason I was interested in using an AC demagnetizer, but I think the intense heat approach works more effectively with strong magnets.
Know anyone who’s got an induction-type electric stove?
No, unfortunately.
One of the biggest industrial drawbacks of neodymium magnets is the relatively low resistance to temperature- normal neodymium magnets have a curie temperature around 320 °C or 608 °F.
Didn't know that actually worked. Where does the magnetism go after you heat it up? Does the reverse work as well? (cooling it down to get the magenitsm back?)
Maybe I should try the heat-application method, then. Aluminum melts at 660 degrees C. Maybe I won’t risk deforming a tailcap made of aluminum by using a small heat gun or butane torch on the magnet enclosed therein. The aluminum could be deformed at that temperature, though, so it is risky.
Can’t just pry out the magnet or nuttin’?
In some cases, the magnet is sealed into the tailcap. I am going to try using a hobby knife to open the covering and extract the magnet. I don’t think that’s possible in many cases, but it’s easy to try.
It doesn’t have to be extremely hot.
I accidentally demagnetized a rather strong tailcap magnet of a Skilhunt angle light once, and it can’t have been more than 200°C.
I estimate it was 125°C (but it may have been more) and i remember i was surprised that it was enough to make it lose it’s magnetism.
YMMV.
No.
No, but IIRC, if you heat it up, then cool it slowly in a strong magnetic field, that will align the magnetic domains in the metal and re-magnetize it.
Usually the glue fails about at the same temperature or earlier than demagnetizing the magnet
with another strong magnet you can easily pull out the tail magnet while heating up if the glue fails first
That’s interesting. That seems to be what I’d assume is well below the Curie point for iron, which is over 700 C.