Re: newbie tech question

[casa@unm.edu (Jim Pittman)]

Re:

> Subject: newbie tech question Date: Tue, 20 Oct 1998 12:15:33 -0400
> From: Art Clark <aclark@NOSPAMessential.org>
> Newsgroups: comp.sys.apple2
> 
> Several of the tools that I'm using for working on my old Apples
> have slowly become magnetized.  How can I demagnetize them?
> 
> Art Clark

One way, for small tools like screwdrivers, is to use the gun type
soldering iron that has a "loop" of wire with the soldering tip at
the end. Hold up the gun, click the trigger "on" and then SLOWLY
insert the business end of the screwdriver into the loop up to the
handle, and just as slowly, pull it out. When it's some distance from
the soldering gun, let go the trigger to let the gun turn off.

1) Obviously, don't touch the "loop" because it will be getting hot.
2) The screwdriver will vibrate from the alternating current (the
   alternating magnetic field is magnetizing the steel tool, first
   one direction, then the other).
3) By removing the steel tool SLOWLY the magnetization effect will
   diminish with distance, eventually leaving the tool with a tiny
   and hopefully insignificant residual magnetization.
4) I wouldn't suggest getting a wristwatch too close to the gun.

If you do this and let go the trigger of the soldering gun while the
steel tool is still inside the magnetic field from the gun's loop,
the steel tool will likely be strongly magnetized! So don't let the
gun turn off, and pull the tool out slowly to some significant
distance (maybe 12 inches / 30 cm) before turning off the gun.

Obviously, this would not work with a soldering gun that used DC
electricity (are there any such?) because the effect depends on the
presence of a strong and rapidly alternating magnetic field.

My ][ cents from college physics lab back in the middle ages,

- Jim Pittman - AppleQuerque Computer Club - casa at unm dot edu