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MDH33
05-17-2011, 11:28 AM
Anyone have an idea how to build a demagnetizer? I have a saw I'm trying to sharpen and all the filings are sticking to a section of it which makes it really tough to work with.

DaveInDenver
05-17-2011, 11:39 AM
Google "degaussing coil"

http://www.kerrywong.com/2010/01/18/building-a-degaussing-coil/

http://wiki.answers.com/Q/How_can_you_demagnetize_metal_and_what_is_the_concept_of_a_demagnetizer

subzali
05-17-2011, 11:42 AM
Drop it a few times if you can.

Some other ideas - I bet the Black Hole down in Los Alamos had something that would work for this purpose - too bad I'm not taking a trip down there anytime soon.
http://www.groupsrv.com/hobby/about188239.html

MDH33
05-18-2011, 08:33 AM
Thanks for the info guys. Do you think a bulk tape degausser would be strong enough to demagnetize a sheet of steel? I found several on FleaBay cheap.

DaveInDenver
05-18-2011, 08:50 AM
What kind of steel is it and how thick? A tape eraser probably won't be very strong, so my guess is no. How much are they going for on eBay? If it was me, I'd buy a 500-foot spool of 24AWG magnet wire and wind a monster one. Can't imagine a spool would be more than $20~$40. Other than a huge coil, a degausser is a switch and a plug. I would also put a 100W bulb in series (while you can still get them) to limit the current a little.

60wag
05-18-2011, 08:52 AM
If you could something like this used:

http://www1.mscdirect.com/CGI/NNSRIT2?PMPXNO=4765684&PMTERM=09041500

It'd probably work much better.

DaveInDenver
05-18-2011, 08:54 AM
Bruce's link is to an industrial version of exactly what you need. It's $150.

That buys A LOT of magnet wire...

http://bbs.homeshopmachinist.net/showthread.php?t=47853

If you want to experiment, I have a Variac you can use.

Rezarf
05-18-2011, 12:47 PM
Heat it up to cherry glowing red ;)

2nd Childhood
05-18-2011, 07:24 PM
A coil of wire is the way to do it. The 100W lamp in series is also a plus. I dont know that the wire (depending on the length) would have enough resistance to keep a breaker from tripping. I would go with that one. Finding the wire is another story, since all copper and precious metals are ending up in a scrap yard. Even metal in use is getting ripped out by thieves these days.

Air Randy
05-19-2011, 09:03 AM
How about the least expensive option to just buy a new saw blade? :D

Jacket
05-19-2011, 09:20 AM
I guess you haven't seen Martin's saw blades. :)

DaveInDenver
05-19-2011, 09:31 AM
I guess you haven't seen Martin's saw blades. :)
Not a throw-away hack saw blade he's working on. Big cross cut saw I'm assuming.

60wag
05-19-2011, 10:30 AM
Here's Martin taking a break from some trail work with his saw:

DaveInDenver
05-19-2011, 10:34 AM
http://www.tvacres.com/images/lumberjack.jpg http://dawnsearlylight.blogs.com/graphics/Monty_Python_lumberjack.jpg

The Lumberjack Song

I'm a lumberjack and I'm OK,
I sleep all night and I work all day.

He's a lumberjack and he's OK,
He sleeps all night and works all day.

I cut down trees, I eat my lunch,
I go to the lavatory.
On Wednesdays I go shopping,
And have buttered scones for tea.

I'm a lumberjack and I'm OK,
I sleep all night and I work all day.

He's a lumberjack and he's OK,
He sleeps all night and works all day.

He cuts down trees, eats his lunch,
Goes to the lavatory.
On Wednesdays he goes shopping,
And has buttered scones for tea.

I'm a lumberjack and I'm OK,
I sleep all night and I work all day.

He's a lumberjack and he's OK,
He sleeps all night and works all day.

I cut down trees, I skip and jump,
I like to press wild flowers,
I put on women's clothing,
And hang around in bars..

He cuts down trees, he skips and jumps,
He likes to press wild flowers,
He put on women's clothing,
And hang around in bars?!.

I'm a lumberjack and I'm OK,
I sleep all night and I work all day.

He's a lumberjack and he's OK,
He sleeps all night and works all day.

I cut down trees, I wear high heels,
Suspenders and a bra,
I wish I were a girlie,
Just like my dear papa.

He cuts down trees, he wears...high heels?
Suspenders...and a bra?
He wants to be a girlie,
Just like his dear papa?

I'm a lumberjack and I'm OK,
I sleep all night and I work all day.

He's a lumberjack and he's OK,
He sleeps all night and works all day.

DaveInDenver
05-19-2011, 10:34 AM
http://luckypuppy.bravehost.com/GALLERY/galleries/Humor/lumberjack_commandos.jpg

60wag
05-20-2011, 06:01 AM
How about a vintage demagnetizer for a vintage saw?

http://cgi.ebay.com/ANTIQUE-G-S-DEMAGNETIZER-WATCHES-CLOCKS-TOOLS-/300527254374

Or something a bit more economical:

http://cgi.ebay.com/PLATE-DEMAGNETIZER-6-1-2-X-4-1-2-TOOL-DIES-CUTTERS-NEW-/330521359240