magnetized tools - Page 1
Forum section: electronics / beginners

author: m3vuv
author_rank: Super Contributor
timestamp: December 21, 2019, 07:31:27 pm
content: Hi all,a lot of my small screwdrivers etc have become magnatized,does anyone know of a simple wat to de magnetise them?,cheers m3vuv 73.

author: Yansi
author_rank: Super Contributor
timestamp: December 21, 2019, 07:36:50 pm
content: put in a proximity of a low frequency AC electromagnet and slowly move away.

author: Domagoj T
author_rank: Frequent Contributor
timestamp: December 21, 2019, 07:38:50 pm
content: Or get this thing:https://www.banggood.com/Wowstick-Magnetizer-Demagnetizer-For-Mijia-Kits-1FS1F1P-Electric-Screwdrivers-p-1333573.html?cur_warehouse=CN

author: bob91343
author_rank: Super Contributor
timestamp: December 21, 2019, 07:54:23 pm
content: I have two very old tape erasers and perhaps a tape head demagnetizer that do the job well. I doubt those are still available but check at swap meets.

author: JDubU
author_rank: Frequent Contributor
timestamp: December 21, 2019, 08:12:00 pm
content: Here are more choices for a magnetizer/demagnetizer tool:https://www.amazon.com/s?k=demagnetizer%2Fmagnetizer&crid=I7W155MQ20MT&sprefix=demag%2Caps%2C249&ref=nb_sb_ss_i_4_5I consider it to be one of the essential tools to have, especially if you are working with very small screws in tight places.

author: james_s
author_rank: Super Contributor
timestamp: December 21, 2019, 08:44:19 pm
content: CRT degaussing wands and coils used to be readily available. You can use any kind of electromagnet powered by AC though. The coil salvaged from an old shaded pole motor would probably work well for degaussing screwdrivers.

author: m3vuv
author_rank: Super Contributor
timestamp: December 21, 2019, 09:22:12 pm
content: would holding them next to a rewound(secondary) mot work?

author: Kleinstein
author_rank: Super Contributor
timestamp: December 21, 2019, 09:38:59 pm
content: Just the outside of a motor will not produce much field. So this would not work. It would usually need a modification (e.g. remove the rotor) this may well require to run at a reduced voltage too. A possible source for a suitable AC magnet could be an AC relay, or some linear magnetic actuators. Motors tend to be relatively large. There are possibly several options in the junk bin.There are also some permanent magnet solutions to get a reasonable demagnetization. There are some that combine magnetize and demagnetize. It is not as good as an AC field be it could be good enough.

author: Yansi
author_rank: Super Contributor
timestamp: December 22, 2019, 12:01:51 am
content: "MOT" was likely a Microwave Oven Transformer.OP: No, it won't work that way. You need the magnetic flux to go through your screwdriver. The core of the transformer would need to be cut (the I section of the core ground off off the MOT, but then you could only run it with lowered voltage input).

author: mcovington
author_rank: Regular Contributor
timestamp: December 22, 2019, 12:11:21 am
content: Do you happen to have a Weller soldering gun? Put the tools near the body of the gun (not the tip), pull the trigger, and gradually pull the tools away while the gun is still on, then release the trigger.

author: themadhippy
author_rank: Super Contributor
timestamp: December 28, 2019, 05:57:33 pm
content: Give them a short sharp shock,bang the screwdriver against the work bench or lump of metal a few times.

author: AKM
author_rank: Contributor
timestamp: December 28, 2019, 08:29:59 pm
content: You can use a magnet. Rub against either pole to magnetize, rub against the side where you have both poles to demagnetize.Here is a picture of a magnetizer/demagnetizer to easily demonstrate.

author: GreyWoolfe
author_rank: Unknown
timestamp: December 29, 2019, 02:21:55 am
content: Just out of curiosity, why do you want to demagnetize? I buy magnetized kits and if I have stuff not magnetized already like my Xcelite 99 series, I magnetize them. I even keep a magnetizer/demagnetizer in my tool bag in case anything gets weak. Never have had an issue in 20 years of field service repairs.

author: jmelson
author_rank: Super Contributor
timestamp: December 29, 2019, 05:36:41 pm
content: Best thing in the world is one of the old Weller transformer-type soldering guns, the ones with the two-pronged copper tip that is bolted into twothreaded posts that stick out the front of the gun. You squeeze the trigger and then pass the tool through the loop of the tip, pull back outand then hold far away from the gun when you release the trigger. This totally demagnetizes the tool.Jon

author: Kleinstein
author_rank: Super Contributor
timestamp: December 29, 2019, 06:06:23 pm
content: Quote from: GreyWoolfe on December 29, 2019, 02:21:55 amIt depends on the job. For some tasks a magnetic tool is good and for others it is causing problems. With a magnetic screw driver the screw on the heat tends to hit the side of a magnetic material. It is especially trouble with a magnetic washer. Magnetized tweezers can be troublesome with small parts - here stainless steel is a common solution, as the magnetic version does not make much sense.The cases are rare but sometimes one wants it non magnetic.

author: bob91343
author_rank: Super Contributor
timestamp: December 29, 2019, 06:58:37 pm
content: Yes magneetized tools can be a nuisance, in particular with small parts.Additionally, magnetic tools can magnetize delicate mechanism parts and affect operation. A clock or watch movement is an example.I demagnitize my tools occasionally. Scredrivers in particular. I have some tweezers that cannot be magnetized and use those occasionally. They are braxx or fiber.