Thread
:
mag base remagnetizing
View Single Post
#
26
Posted to rec.crafts.metalworking
Jim Wilkins[_2_]
external usenet poster
Posts: 5,888
mag base remagnetizing
"Robert Nichols" wrote
in message ...
On 3/24/20 3:10 PM, Clare Snyder wrote:
On Tue, 24 Mar 2020 09:14:40 -0700,
wrote:
On Tue, 24 Mar 2020 00:26:44 -0700 (PDT), whit3rd
wrote:
On Tuesday, March 17, 2020 at 11:06:10 AM UTC-7,
wrote:
On Sat, 14 Mar 2020 21:25:20 +0000 (UTC), Cydrome Leader
The alnico
magnets in old and/or inexpensive mag bases were/are magnetized
after
assembly. This takes a LOT of current. I have seen the setups
for
doing this and they are not trivial.
There's a two-part magnetization process for alnico, you have to
observe the
built-in (at ceramic-firing time) polarity when you apply
current.
It WILL magnetize one direction, not the other.
Usually, metalworkers have access to high DC current sources from
Lincoln, Miller,
Hobart, etc. and that's what it'll take.
My 300 amp Miller would not provide enough current for decent
magnetization. Not even close.
Eric
Might work to charge the capacitor bank, but definitely won't do
the
magnetizing unless you have a lot of turns - it's ampere turns that
make the feild strength - and too many turns increase the
inductance/reluctance and slow down both the build-up and collapse
of
the feild.
The setups from some of the experimenters that use high-current
pulses to
shrink coins might be a good place to start.
https://www.google.com/search?as_q=shrink+coin
Delivering 100,000 Amperes from capacitors charged to 12,000 Volts
is a bit
of a challenge, though.
--
Bob Nichols AT comcast.net I am "RNichols42"
12KV arcing across contacts is enough to generate X-rays.
Reply With Quote
Jim Wilkins[_2_]
View Public Profile
Find all posts by Jim Wilkins[_2_]