On Sun, 31 Oct 2010 21:14:53 -0700, Tim Wescott
wrote:

On 10/31/2010 08:57 PM, Steve B wrote:
I want to make a knife bar out of rare earth magnets to hold my kitchen
knives. If I hold the surface of the knives off just a tad, can I avoid the
scratching that would be produced with the knives touching metal to metal?
Or will there be enough magnetic attraction if I use thicker magnets to suck
them up against a oak or plastic substrate that would be sufficient to keep
them in place, and a few thousandths of airspace between?

Or lastly, to apply a thin plastic face onto the magnet so that it never
touches metal to metal?

If you get some 1/2 inch wide rare earth magnets, manage to glue them up
in a continuous bar without putting an eye out from flying shards, put a
thin piece of teflon tape over them and stick a knife on -- you'll be
grunting and looking for a nice bronze crowbar to get your knife un-stuck.

Use big enough magnets (1/2 or 1 inch wide, 1/4" thick) and you can
probably bury them under 1/16" or even 1/8" of veneer. Experiment first
-- those things are damn strong.

I remember playing with half of a linear force motor at an old place of
employment one day. It used big square rare earth magnets -- something
like 1/4" thick by 1.5" on a side, glued to a carrier. They came stuck
to a piece of sheet steel, taped to a regular old piece of corrugated
cardboard. The sheet steel was to keep them from whapping into anything
_else_ magnetic, the cardboard was to space them away from the steel
enough that a human being could pull them off the steel.

Personally, I'd check and see if Radio Shack still sells those big
rectangular ceramic magnets. They're plenty strong, but not as over the
top as rare earth magnets.


A further note..be sure all of your knives will stick to a magnet. Ive
got some stainless ones in the kitchen that are non magnetic.....


"Confiscating wealth from those who have earned it, inherited it,
or got lucky is never going to help 'the poor.' Poverty isn't
caused by some people having more money than others, just as obesity
isn't caused by McDonald's serving super-sized orders of French fries
Poverty, like obesity, is caused by the life choices that dictate
results." - John Tucci,