What happens if you keep using the wrong sharpening stone?

i use sandpaper which uses carborundum (600 to say 2000). the cheaper ones, i suspect, contain only silica because i tried to polish an s30v military and it hardly wore out the original grind when done purely by hand. i had to tape the paper on a wooden block, and run the blade across it with pressure, a bit like those japanese sword polishers.

as jason explained in a previous thread, a high-vanadium blade is a like a concreted road. when new, the surface is pure concrete. in time, the concrete disintegrates and the rock aggregates are exposed. using a medium that's softer than the rock (say tires in conjunction with sand from the worn cement), you will keep eating at the cement and the rocks will jut out more.
 
hank_rearden said:
^
sorry, i meant aluminum oxide sandpaper, but probably with fakes that only use silica.
Click to expand...

Some sandpapers, intended for wood only, use garnet abrasive (which is a natural silica-based abrasive). Not 'fake', but just a different material intended for different use. The garnet papers are usually amber/light brown in color, though some aluminum oxide sandpapers will also be brown. Better brands like 3M or Norton will usually make it very clear in the naming or labelling of them, as well as providing info for intended use, i.e. 'wood only', 'plastics', 'metals', 'all materials', etc. Papers labelled 'for metals' or 'all materials' should always be aluminum oxide (brown/amber, lighter grey, blue, pink, purple) or SiC (dark grey or black), and 'wood only' or 'bare woods' would likely be garnet.


David
 
Last edited:
Keep in mind as well, sandpapers labelled for "all materials" implying use on steel, are generally intended for unhardened steel. As a matter of what is practical, only the newer ceramic and silicon carbide work well on hardened steel, though regular paper will still abrade. Is easiest to see whether the paper is a no-load, open coat or a closed coat material. Most of the tan sandpaper for woodworking and mixed materials will be open coat. In addition to the mineral not generally being effective on hardened steel and dulling quickly, it also produces a very aggressive finish compared to the same grit size on a closed coat sheet. A world of difference between 600 grit sheet made for wood/general purpose and a 600 grit sheet of silicon carbide wet/dry.
 
You must log in or register to reply here.
Back
Top