Putty Questions

The lower the number, the thicker and coarser the finish...  for filling a rough surface you would use 500... for a super finish go with 1200 or 1500...

http://www.missing-lynx.com/reviews/other/mrsurfacerreviewbg_1.html

Hmmm: For your last question--2500 Grit WET!

Micro-Mesh sanding pads and sheets range from 1500 to 12000.  You can achieve a mirror-like finish.  Use wet and don't skip a number.  

Available from many online hobby retailers, I have found a set also available at Rockler woodworking supply or Woodcraft

EdGrune

Micro-Mesh sanding pads and sheets range from 1500 to 12000.  You can achieve a mirror-like finish.  Use wet and don't skip a number.  

Available from many online hobby retailers, I have found a set also available at Rockler woodworking supply or Woodcraft

 

I use the MicroMesh pads, sticks, and sheets, depending on the situation.