by raimundo » 21 Jan 2012 11:17
for curved shapes like getting down in the valleys of a bogota type pick, wrap some sandpaper around some sturdy bamboo chopstick and then hold the chopstick and move the pick on it. for flats like the sides of the pickshafts, of course you use a flat stick with the sandpaper wrapped around it. Ask the hardware where you got the sandpaper for some paint stirring sticks, wrap the sandpaper tightly and rubber band it on the ends.
220 is an agressive sandpaper, that will cut into your workpiece, its good for first sanding that has an element of shapeing involved, you need to watch the effect of this sandpaper as you use it so you don't go to far, and this is hand sanding! not power tooling.
320 is still an aggressive sand paper, and will do final shaping and this is the next level in sanding grit that you use to prepare for the 400 grit.
400 and 600 grit are not aggressive and you don't need to worry about going to far with them, you are only using them to make the marks of the 220 and 320 go away.
wet or dry? dry sanding is easy to look at and know where you are as far as getting done, but dry sanding causes the sandpaper to break down into airborne dust, this is not good for optics, cameras, your glasses, etc, and should be done outdoors or in a dirty metalworking place.
wet does not mean dipped in water, its just a few drops that hold the dust down on the stick, instead of becoming airborne, it stays in the tension of the water that holds it on the stick then as it tumbles and breaks down into finer grit.
new sandpaper is aggressive but as it wears, it becomes finer grit as the grains break into smaller ones. the result is that your metal becomes shinier
Wake up and smell the Kafka!!!