Stupid Magnet Idea

[SparWeb]

WARNING: The following posting contains explicitly

             stupid content and should only be viewed

             by an immature, snide, or opinionated audience.  

             Viewer derision is advised.

Here's something I wish I hadn't done.

Here you can see I was using a hack-saw to slice through a neo magnet.  Pouring water constantly so that they don't catch fire (newbie alert: yes magnets can catch fire - personal experience).  The magnet is hiding between the pieces of angle that I'm using to guide the saw.  The original was a 2" x 1" x 1/2" rectangular magnet with two holes.  I need a 1" square magnets to complete my latest motor conversion.  These magnets were recovered from my wrecked generator, which had 12 magnets.  The new conversion has 8 flats, each of which is 3" long.  Since I had 4 spares after putting on the first 8, all I had to do was cut them in half.  No problem, right?

Nah.

So up there in the photo I'm on my sixth hacksaw blade, and have only 2 left.  I've managed to cut only about 3/8" through each of the four.  Realizing after the second or third blade that I wasn't going to cut all the way through even one, I came up with the plan to cut part-way and score all around, then strike them, and they would break in half.

Don't get ahead of me...

So here is one of the partly cut magnet blocks clamped on the vise.  You can see the ends of a few pieces of angle-steel in the vise jaws so that one end of the magnet can stick and be clamped, and the other end hangs over the edge.  When it falls it sticks to the other angle.  I struck it with a hammer, using an aluminum block to carry the blow.  The last thing I need is a magnetized hammer!

(What am I saying, it would go well with my magnetized screwdrivers, c-clamps, wrenches, measuring tapes, etc....)

Well, here are the eight resulting pieces.  Some aren't that bad.  At least none of them broke through the screw holes, though one came very close.

Why?  Why in the world would I do such a thing?  I have a motor conversion under way that needs more magnets.  The rotor is 3" long, but the magnets I have are all 2" long.  All of these 2" long block magnets are salvaged from my wrecked alternator.  I can't find any 1x1 magnet blocks with the screw hole for sale, not even any with dowel holes.  Been poking around e-bay for a while with no luck.  Still looking and not happy.  Cultivating a love/hate feeling for neodymium.

SAFETY NOTE:

Doing dumb things like this doesn't mean I skipped some safe practice.  

1. Wear gloves.
   
2. Use water or some other fluid bath to prevent them from burning.  I once witnessed the pyrotechnics while counter-sinking a hole.  
   
3. Collect the cuttings, filings and chips and dispose of them in a wad so that they don't get collected in the mechanisms of your tools.  
   
4. Wash your hands and arms thoroughly, with soap, afterward to remove any dust or abrasive powder that may get into your eyes or mouth.
   
5. DON'T BOTHER TRYING THIS - IT DOESN'T WORK.  
   
   

Stay tuned... more goof-ups to come.

[stop4stuff]

wot...

no pics of the effects of magnets in pockets

seriously, +1 to SparWeb for highlighting some of the dangers.

[Old F]

Don't you just love the smell of flaming magnet in the morning : )

Been there done that an have the scorch  marks to prove it.

Old F

[ghurd]

"Stay tuned... more goof-ups to come" ?

I hope that's not insinuating some like me, for example,

would, for example, epoxy a neo on upside down,

Because I will deny it!  

G-

[Madscientist267]

Interesting. But it looks like you've found the perfect place to post this!

Had no idea that magnets were so hard to cut; never tried it myself. And what's this about burning? Sounds like a violent way to end a magnet's life...

Youtube, here I come!

Steve

[Flux]

Not tried with a hacksaw, didn't think it practical and your efforts confirm this but if you got what you need then good enough.

I did have good luck with a tile cutter ( diamond saw) it was quick and as long as you held the both parts of the magnet firm when the cut went through the process was tame.

Plenty of water is essential. The same tile cutter works well with ceramic magnets, you would have no chance there with a hacksaw.

I suspect an angle grinder with diamond wheel would also work but it would be a challenge to keep the water out of the electrical bits of the grinder but it would be quick and the thing may work in a poly bag without air cooling for a few seconds to do the cut.

Flux

[SparWeb]

I never thought of the tile-cutting saw, but the diamond blade probably would be okay.  Probably best not to say, when renting or borrowing one, that magnetic dust particles will fly around and I'd be spraying water all over it!

I finally found the magnet I needed, anyway.  K&J Magnetics, for anyone who's interested.  From their website:

[electrak]

instead of an angle grinder, use an air powered cut-off saw, most of them are aluminum, and can be used underwater if so desired. I don't know if you can get diamond wheels for them, but the nornal one are cheap.

[Airstream]

Anyone tried quenching those type (non-composite, looks like cast metal) Neo Magnets with dry ice and then take advantage of temperature embrittlement?

I would think it may be possible to get a crack to propagate similar to cutting glass - firmly gripped and 'bent' over a fulcrum point (think sheet metal brake) with a corresponding line scribed just like when cutting glass: Once the force is placed (like hinge bending) working with extremely sharp chisel and small hammer might guide the fracture...

[electrondady1]

i wet tile saw is the way to go.

my nephew bought the cheapest one for about 100 bucks.

did his tile job and them gave it to me.

with it , i have cut up hundreds of ceramic mags.

even grinding them down to get a consistent thickness.

and cut up hundreds of hard drive  mags.

never a problem.

and all the muck is captured in the saw and can be retried later

i have not cut up any large mags like those shown.

 

[bj]

Sparweb--along the same lines, I wanted to cut down one of the big neo rings that I have.  Involved setup to do, but used a 5 inch angle grinder

with a zip (1/64) disk, and LOTS of water.  It actually did a nice job.

I accidently stepped on the water hose about half way through.  The resulting flame blast got me off the hose in a nanosecond.  Neo is fun

stuff.

bj

[SparWeb]

Hey look whose birthday it is today...

Hans Christian Oersted basically got the whole magnet+coil=current business going 200 years ago.

Did anybody notice that Google did a logo for Tesla's birthday too?

[SparWeb]

Here it is: