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wratterus
25-07-2011, 04:55 PM
Funny story...

I've got a really nice set of Cabac magnetic tipped screwdrivers. Was pulling apart the screen in a V6000, one of the magnets that holds the lid shut had come loose and I managed to accidentally stick the screwdriver to it. Ever since the screwdriver's magnetism has been weak/near useless. It use to be great, could unscrew and remove screws recessed into a laptop base with no issue at all, you could put screws on it and lower them down vertically with no problem at all.

Now half the time the screw just falls off, and there is no way it could actually lift a screw out of a laptop.

Does anyone know how I would go about fixing that? Perhaps pull apart a dead HDD and try to somehow re-magnetize the screwdriver? Is that even possible? :lol:

Thanks. :cool:

robsonde
25-07-2011, 05:03 PM
yep, find a strong magnet (hard drives are good choice)

drag the tip of the screw driver down the length of the magnet, ensure you have good contact with the magnet.
repeat about 20 times and test.
do another 20 times if needed.


google will have nice videos of doing this correctly.

wratterus
25-07-2011, 05:06 PM
Sweet, cheers. Will give that a go when I have a minute.

wratterus
25-07-2011, 05:26 PM
That's worked a charm, thanks! :thumbs:

CliveM
25-07-2011, 05:59 PM
The other way which works well is to wrap a coil of heavy copper wire around the end of the screwdriver. I used about 8 turns. Hook one end of the wire to a 12 volt car battery terminal. Then brush the other end of the wire across the other battery terminal. Do not hold it on just brush it across otherwise it will get real hot real fast. Magnetizes it fast.

pctek
25-07-2011, 06:14 PM
yep, find a strong magnet
drag the tip of the screw driver down the length of the magnet.

I have one sitting near by. I just randomly move the screwdriver over it, works great.

Haven't managed to un-magnetize one yet, didn't know you could, we learn something new every day.

Billy T
25-07-2011, 06:50 PM
Haven't managed to un-magnetize one yet, didn't know you could, we learn something new every day.

A decaying AC field will do it nicely. Hold a screwdriver along the edge of a CRT monitor screen (yes some of us still have them) that has been off for 15 minutes or so then switch it on. You should hear and feel the buzz. It has to be a decaying field or there's an odds on bet the switchoff pulse will magnetise it instead. Jaycar sell a static field magnetiser/demagnetiser but it is a bit of a lottery knowing which way to drag the tool through it, you might demagnetise it worse.

TVNZ had some video tape erasers that just about slowed the rotation of the planet when you switched them on. They were so powerful that non-magnetic items could get hooked up by the eddy currents induced in their metal. It wasn't a strong hold, but they'd stick there buzzing a bit.

Probably killed a few watches too.

Cheers

Billy 8-{)

pctek
27-07-2011, 09:34 PM
TVNZ had some video tape erasers that just about slowed the rotation of the planet when you switched them on.

:lol:

Happy Harry
27-07-2011, 09:58 PM
About a gazzilion years, ago I build a magnetizer out of a 230V hollow solenoid.
Half wave rectified the 230 volts so the current only runs one way thru the coil, an inline switch(sprung off) and 3 pin plug completes the circuit. Shove the screwdrive in the centre of the coil, power on and slowly pull the screwdriver out of the coil. Works well and still using it today.
Before that, we use to just used a insulated heavy gauge wire wrapped around the swrewdriver blade. One end hooked to phase, the other to a piece of 5amp fuse wire and the other end of the fuse wire to neutral. All mounted to a board for ease of use. Power on, the fuse wire went bang and the screw driver was magnetised. All the techs used it for years until a little sanity (electrical inspector went ballistic) prevailed.

HH