I wonder if it would fly out or immediately stick to the tool.


I think it would fly out and not stick to the tool. Maybe, just maybe, the
metal tool/toolrest/etc. would affect it's trajectory though IF the magnet
decided to leave the wood really close to where the tool/toolrest was along
the circumference of the wood piece it was embedded in. Depends on the
speed at which the magnet was sent flying in the first place too I
guess(ed).

To test this (I love testing things!), just about an hour ago I put a 2"
wide skew (high carbon not HSS) in a vice pointing straight up and the wide,
flat part parallel with me. I made a little magnet firing gun out of an old
compressor pea-shooter I made once. Basically just a quick opening valve
with a piece of small diameter PVC connected to the compressor. I set it up
so that it would fire the magnets next too the skew at about 3" away. Then
I tried it at 2", 1" and 1/2" away as well. I had the "gun" 2 feet away
from the skew at all times. I shot it 20 times at each distance and then
turned the skew 90 degrees so it was facing me with it's wide, flat part.
My conclusion....

- The magnet never stuck to the skew until I was firing at the 1/2" distance
and only when the skew flat part was faced away from me. Even then, it only
stuck 4 times. The magnet wasn't traveling nearly as fast as it would have
been spinning even at 1000 rpm *I think*. I didn't measure the speed but it
didn't look as fast as those chucks of wood flying past me when I blow up a
bowl.

- I'd like to set up again sometime and see if the trajectory of the magnet
does, indeed, change as it passes by the steel tool.


I don't think the wood will make much difference in the force between the
magnets. It is a function of the separation and magnetic permeability of
the material between them. I just tried a little experiment with some
3/8" dia. 0.2"thk. rare earth magnets (this size can already be tough to
separate). I put them on either side of my finger and they stayed in
place.
I then tried it with a similar thickness of wood and noticed no
difference.
I also tried how close to the table one magnet has to be to get the other
to
jump up to it and noticed no difference with nothing, finger or wood.
Just
to put some numbers to this, the magnets would jump together when separate
by about an inch with half of that space occuppied by wood. These might
be
larger than he is willing to embed.


Yeah, I was thinking more along the lines of the density of the wood and
wood specie affecting how thin you could get the distance between the magnet
and the outside of the wood. You can get hond. rosewood fairly thin and
still be pretty strong. The same can't be said of sycamore, for instance.
Those NIB magnets can get a pretty good pull going and I was wondering how
much attaching/detaching of the two pieces of the turnings would hold up to
such a thing. You'd need a greater distance between the 2 magnets (more
wood between them and the outsides of the pieces) to give you something that
would hold up to the abuse in sycamore and that increased distance will
affect the magnets holding power.

However, I got to thinking of what you thought I meant and decided to give
it a test (did I mention I love testing things?). I know that outside
factors such as temperature affects the strength of magnets but I was
wondering if the density of a material separating 2 magnets would really
affect their strength. This was a really simple test with no quantitative
measuring equipment though. No potential for harm = no fun. All I did was
just take some different wood species at different thicknesses and see if
the magnets would hold.

I first used balsa, mahagony, hard maple, and kingwood in 1/2" thicknesses
with the same 3/8" diameter NIB magnets I used in the previous test.
Couldn't tell a difference. I went up to 3/4" with the same woods. No
difference between the wood species. I went up to 1". Aha! The balsa was
holding (barely) but the kingwood wasn't nearly as much. So, I needed a
more dense (or I think they are) wood to see if this was something. I used
some snakewood and then some lignum vitae at 1" thickness. Yep, those
didn't hold at all. There's not a huge difference but it's noticable. Yes,
there's a big difference in the density of the balsa compared to the
snakewood and lignum vitae and just the slightest difference in the hold of
the magnets between those 2 extremes. I couldn't tell a difference between
the mahogany, maple and kingwood which I'd call a medium to high density in
what we normally work with. The snakewood and lignum vitae are what I'd
call very high density woods.

Of course, these are highly unscientific tests. Way too many factors left
unaccounted for. But, it was an interesting lunch break anyway. I'd like
to hear if you've done your own tests and how they worked out.

- Andrew