"David Billington" wrote in message
news
On 18/10/17 22:05, Bob La Londe wrote:
Hi guys. I need to machine away the corner of a neodymium magnet
that needs to go into a hole in a mold. One of the passages for a
core intersects the hole the magnet is going to get pressed into.
There really isn't any other place to put the magnet, and the core
is a necessary part of the casting.

Any tips or suggestions?

The best thing I can think of is to just use the little bench top
belt grinder.

The problem is if the prototype is satisfactory I may find myself
making a bunch of these molds. Hand grinding one is no big deal. 20
or a hundred... well that could be pretty time consuming.

I know they are fragile. That's why I think grinding is the best
option for just one. I do not want to put a grinding wheel on one
of my mills, and the little no-name mill drill still comes in handy
from time to time (I used it today), so I'm not crazy about filling
it up with grit either.




What I've read about those magnets is that they aren't recommended
for machining as the dust is easy to ignite. Also if using to hold a
core in a mould IIRC the magnetic properties are lost at low
temperature of less than 100C so you may be better off looking for
another solution.


https://www.kjmagnetics.com/neomaginfo.asp
"Machining the magnets will generate heat, which if not carefully
controlled, can demagnetize the magnet or even ignite the material
which is toxic when burned."