drilling ceramic magnets

Puggie

Member
2004-10-11 5:21 pm
Is there any nice DIY methods for drilling ceramic speakers magnets. I have a motor that is 3 parts bonded together (top plate, magnet and polepiece/base plate). I would like to drill and couter sink the top plate and baseplate/polepiece then drill the magnets so I can bolt the structure together instead of bonding it. This is so it can be dissasembled easily for 'experimantal modifications' (see my post on Faraday rings if you what and idea of what I'm looking at).

I presume I need stainless fixings so as they are non magnetic but how do I go about drilling the magnet? what sort of drill should I use and what cutting fluid? Also can this be done with it still magnetised (I don't have facilities to re-magnetise it)
 
I successfully drilled a number of magetized 20oz ceramic magnets to fit a #6 machine screws, so yes it is possible. I used a drill press set at highest speed, your standard off-the-shelf cutting fluid and a fancy drill-like grinding bit I got from Snap-On.

Unfortunately I don't have any specifics on the Snap-On bit used (I checked the web site and couldn't find anything resembling it), but it had a rounded end and very tight turns up the shaft. As mentioned it looked more like it was meant for grinding, but the Snap-On rep said to try it. Luckily for me it worked.

I drilled three holes per magnet and took my time at it, making sure to wipe the residual particles off. A bit of a pain since they are magetized and loved to stick around.

Hope this helps you. Perhaps someone can chime in to give a more specific name to the bit I described.

Mark
 

Puggie

Member
2004-10-11 5:21 pm
thanks guys at least now I know its possible.

I figured cooling would be a big issue, the only think I had thought of using is some DIY stores in the UK sell drill bits for drilling ceramic tiles, I thought this may be possible, I may have to go speak to some tool shops though see what is available that looks like a diamond tipped grinding bit sort of thing.
 

bigredox

Member
2018-09-26 10:42 pm
Glass and tile bits

Small hole saw or spearpoint bit with carbide tip, high speed, minimal pressure, cutting oil, and a heatsink sandwich. Only do a little at a time and let cool before continuing. Try to imagine drilling into a marshmallow. Then do that with a scrap magnet for practice.