I seemed to have magnetized the table on my Atlas MFC mill...........

I dedicated one of my 100/140 w soldering guns for demagnetizing. Instead of the soldering tip, I used a 1-1/2" diameter single turn loop of 10 AWG copper wire (about 5"). With magnetizing/demagetizing coils, it's all about ampere-turns. Ten turns carrying 1 amp is equivalent to 1 turn carrying 10 amps.
Magnetic flux is proportional to amp-turns. My single turn demagnetizer reads about 310 amps on clamp-on ammeter and the magnetic flux is 310 amp-turns. 10AWG has a resistance of about 1 milliohm/ft. so my loop has a total resistance of about .4 milliohms. If I used a two loops with a total resistance of .8 milliohms, I would expect the current to drop to around 155 amps but I would still have 310 ampere-turns. So, with 3 turns and 15 inches of wire, the current would be just over 100 amps but the magnetic flux would still be 310 amp-turns.
The 1-1/2" loop is great for demagnetizing screwdrivers and small wrenches but I sometimes have a need to demagnetize larger items. I can't just take the 10" of 10 AWG wire and make a 3" diameter loop because although the current draw is the same as for the smaller loop with two turns, I now have just a single turn so the magnetic flux has dropped to 155 amp-turns.
However, I go to a larger wire size, say 7AWG, the resistance will drop to .5 milliohms/ft and the resistance of my 3" loop will .4 milliohms. The current will be 310 amps and magnetic flux for this 3" loop will be 310 amp-turns, as before. Actually, since 7AWG wire is not a common size, I would probably use 12" of 6AWG for a resistance of .4 ohms and a diameter of 3.8". Note that the larger wire won't fit the soldering gun as is. I would have to make adapter studs which would thread into my gun and provided a post for the 6AWG wire.
 
Well guys, everyone get "warmed up" to give me mega servings of crap. I found the source of the magnetism, and it MY BONEHEAD FAULT. Yet, resolving the issue was pretty simple. So, you know those magnetic parts plates you buy at Harbor Fright? Guess who set one on the back side of the mill temporarily and forgot it was there. Dang thing magnetized the whole machine. When I removed it, Shazaam! 99% of the magnetism gone. Since the source of the magnetism is now gone, I am willing to bet that the last little bit of residual magnetism disappears on it's own.

God, I feel stupid.............and happy that the case is solved. Just call me Forrest "stupid is as stupid does"
 
I had an issue with the table on my Bridgeport getting magnetized awhile back. It went away over time.

I do own some of those "magnet bowls" and I probably could've set it down on the table at one time or another!

Thanks for "owning up" to your "bonehead mistake"! ;)
 
The Truth Shall Set You Free

 
I’d like to see a picture of the offending object if you have time. I’m interested to see this thing that can mag a whole milling table.
 
Yup, that's it. Incredibly strong magnet on it. magdishHF.jpgHere it is in person:
 
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