With all this talk about ebony dust (and with the price of ebony as it
is there won't be all that much being made!) don't forget that the skin
surface of cast iron is horribly abrasive, and putting a grinder on the
tool post can create terrible problems.
But there's a very easy solution, which I'e used for years. Go to the
grocerty store and get the extra-heavy duty (not merely heavy duty)
aluminum foil. wrap it around everything, til the lathe looks like
it's a turkey ready for the oven. Unlike the old method of draping oily
rags, which can be very dangerous if a piece of rag gets picked up by
the spindle or chuch, the foil will just tear a little bit and stay in
place. If you're using the cross slide then obviusly you do have to
leave the lathe bed exposed, but that's a lot easier to get clean than
the insides of bearings.
I find the aluminum foil handy not only for that, but for various
coverup jobs. Leave a big sheet under the bed of the lathe, with the
edges turned up, and when it gets swarfed up a bit, ease it out, ball
it up, and throw it in the garbage can.
(British readers are encouraged to use aluMINIUM, instead, but it
doesn't work quite as well)