Sandpaper Grit question

The meaning of the number varies by country/manufacturer. Higher numbers are always finer, but compare Testors 800 grit sanding film to 3M wet/dry, and and the difference is night and day. Problem is, manufacturers rarely tell you which scale they use (even in the US). The Euro standard has a "P" before the grit number, you may have seen this in a woodworking store.

And then there is Micromesh, which uses a different scale altogether.

Here are links to a couple of conversion charts. I find them quite helpful. Note that if you are using 1500 grit in the US ANSI standard, then switch to 1800 in Micromesh, you are actually getting a coarser grit, not finer.

https://www.fine-tools.com/G10019.html

http://www.sisweb.com/micromesh/conversion.htm

Hi ;

 Hey , Baron , I second that motion !

The grit number is the number of sharp particles per square inch, at least here in the US.

I had no idea of the measurement criteria (thanks, Pawal).  But at least here in the states, I have never found a confusion.  All the sandpaper and emory cloth I have ever boughtin a long modeling and car painting lifetime has the same numbering scheme, so just going by the numbers seems to work here.

Hello!

Here's a nice article detailing the subject throughly:

https://en.wikipedia.org/wiki/Sandpaper

Have a nice day

Paweł

The higher the number the finer the grit. For primer you want to work down to very fine polishing cloths starting with around a 1000 and goiung down to about 8000

I don' know what brand sandpaper your getting but some brands tell you on back of package what different grits are used for like 3m sandpaper look at back tells what different grits are used for.