The easiest construction method varies with the facilities and materials that any given constructor has available. 3D printing would be about the hardest method for me.
Printable View
Since making the original post I made a standalone device using the original rotor. I fitted it to a scrap washing machine pump motor, added a switch and encased most of it in a plastic junction box. It sits permanently on the end of a bench ready for immediate use, eliminating the inevitable search for the mislaid rotor and then fitting to a drill. The extra convenience means that it gets used quite regularly rather than continuing to work with a magnetised tool.
Attachment 42812 Attachment 42813 Click for full size.
I just have to remove the keeper, switch on and it is ready to go.
Attachment 42814 Attachment 42815
A couple of typical thingies to demagnetise.
BTW. The keeper is there to prevent the magnets attracting magnetic junk when not in use. That is 100% effective.
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Thanks tonyfoale! We've added your Demagnetizer to our Miscellaneous category,
as well as to your builder page: tonyfoale's Homemade Tools. Your receipt:
<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="https://www.homemadetools.net/homemade-demagnetizer-10"> <img src="/uploads/255169/homemade-demagnetizer-10.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="https://www.homemadetools.net/homemade-demagnetizer-10">Demagnetizer</a> <span> by <a href="https://www.homemadetools.net/builder/tonyfoale">tonyfoale</a></span> </div> <div class="tags">tags: <a href='https://www.homemadetools.net/tag/demagnetizer'>demagnetizer</a> </div> </div> </div> </div>
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