It sounds like an fair idea to me, but why in gods name would you pay 28 bucks for something you could make yourself for 5 or less, just get a piece of the flexible magnet material they use to make signs for the side of cars and cut to fit your filter you got the same thing and a pocket full of extra cash!
I don't think the magnetic sign material will work. It is made so that the magnetic pattern is a thin stripe of North parallel to a thin stripe of South, etc. The magnetic stripes are thin & close together & very weak magnetically (they have a lot of plastic diluting the magnetic material).
There's a nifty trick to demo this: get a credit card fridge magnet & cut off a 1/4" slice from each end.
Put them together so the magnetic sides face & attract each other. Leave some hangover at the ends so you can push/pull each end. Very slowly push/pull the magnets so they slide past each other.
They do a little hopscotching up, then down... (if it doesn't work, go cut off pieces along the other 2 sides)
They alternate between levitating (repeling, S across from S, N across from N) and sticking (opposite poles attract). Note that the attraction is not very strong... so I don't think it'd have much attraction for metal bits in oil... oil that's on the other side of some metal. Magnetic fields get weaker according to the inverse square law: double the distance from the magnet you get 1/ 22 the force... 1/4th. Triple the distance is 1 / 32 or 1/9th the force.
The magnets from inside hard drives are some of the strongest available... nickel plated because the alloy is otherwise rapidly attacked by air. http://www.dansdata.com/magnets.htm
Hard drives are like puzzles to get apart... mini-torx tip screws... some hidden under stickers.
Another option might be to take the cover off garage sale or junk microwave ovens (unpluged & w/ drained capacitor, of course). Remove the magnetron... silver metal, rectangular cube... w/ cooling fins. Take it apart (another puzzle) & get two strong donut magnets.
Frat-house site: http://www.autarchex.com/projects/postmortem_microwave/index.html
But... where to place them & how to hold them there?
Like FOG said the oil filter has already filtered the oil there. Seems like right near the drain plug would be good. then just before draining the warm oil, pull it off... so the metal bits come out with the flow.
Comments? (don't use "quote
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