What is the finest grit sandpaper. Grit 3000 usually marked as p3000. On the cami scale sandpaper grit is measured in microns and to get an idea of how small a micron is check out a piece of 100 grit sandpaper. I have a series of glass plates with wetdry sandpaper attached with 3m77 adhesive. The larger the grit size the more edges there are and the smoother the sandpaper.
Power sanding requires a slower pace than hand sanding. I see from 2000 12000 grit paper. Sandpaper is rated numerically according to the size of the grit particles. The harder the grit material the easier the sanding of surfaces like wood.
Make sure to use water as lubricant wet sanding as it not only helps with quality of sanding but prevents. The density of the grit is important too. Skipping a grit number wont save time. The grit number of sandpaper is almost always clearly printed on the back of the sandpaper itself.
Since coarse sandpaper leaves deeper scratches start with the finest sandpaper that will tackle the project easily and work. I went to a machine shop to see if he could mill down my heatsink and his machine would not be able to hold the heatsink and he recommended some 1200 grit sandpaper but on amazon i see stuff from 3m up to 2000 and other brands as high as 12000. Open coated sandpaper has gaps between the grits allowing sawdust to gather so it doesnt interfere with the sanding whereas closed coated sandpaper doesnt have those open spaces. Sandpaper grit is sized by a gauge number with lower numbers signifying larger coarser grits.
Grit numbers range from 24 all the way up to 1000 although most people will never use grits at the top or bottom of this scale. Use the finest grit size that will handle the task but follow the correct sequence. So for example 24 or 40 grit sandpaper is a very coarse rough sandpaper while 1000 grit paper is extremely fine with very small abrasive particles. The small grains on the sandpaper measure.
A sandpapers grit refers to the size of the abrasive materials on the paper. Youll spend more time sanding with the next grit. I start with 50 grit and then go up through 80 120 220 320 400 600 800 and 1200. Sandpaper may be stearated where a dry lubricant is loaded to the abrasive.
Stearated papers are useful in sanding coats of finish and paint as the stearate soap prevents clogging and increases the useful life of the sandpaper. The lower the number the coarser the grit.