On Wed, 20 Aug 2003 13:47:47 -0700, "Stephen Judge"
For your "Carborundum", try "silicon carbide". The black stuff
commonly sold as wet and dry. It's harder than aluminium oxide and
more appropriate to stonework.
One of your biggest problems will be dust. Unlike wood, stone dust
doesn't compress and so the paper will tend to clog. Keep a vacuum
running as a dust extractor, just to keep the abrasive cutting.
Working it sopping wet will help too.
Ignore the impossible web site, get a paper catalogue. They sell
everything you could ever want.
For a quick fix from the local DIY shed, try the bright orange
Plasplugs tile-fitting tools and get a "tile file" - a grit-covered
latticework. This is a carbide abrasive on an openwork substrate and
good for working dusty stone.
What colour is the slate ? The Chinese stuff is quite soft (but
variable - red / brown is softer), fresh Welsh grey /
purple is hard,
and green Lakeland slate is very tough going.
It seemed a good idea at the time to use the reverse side of some unhoned
slate tiles to get a smooth surface on a window sill. This was thinking I
could easily sand out the cutting marks left on the surface.
I've tried sandpaper, glasspaper, high speed, low speed, by hand, with and
without water, aluminium oxide disk, abrasive flap wheel and Brasso (!).
Hardly seem to shift anything. It's as if the tiles have been hardened in
some way. The marks by the way are barely discernible with a fingernail so
must be a small fraction of a mm deep.
Any ideas out there - someone did mention carborundum paper ?