Replies

1. 
   SRToolguy | Nov 15, 2004 07:06am | #1

   Dude, check out the Mirka Abranet line. I believe it starts at 500.

   Sincerely;

   The Tool Guy

1. 
   hartproject | Nov 16, 2004 12:31am | #3

   I just found some 500 at an autobody store in my area, it's made by 3M. I'd like to check out your brand though too, where can I get it?

1. 
   Pondfish | Nov 16, 2004 02:43am | #5

   You can buy Abralon disks from woodworker's supply: http://www.woodworker.com among other places.

2. 
   forestgirl | Nov 15, 2004 09:48pm | #2

   " still see the 400 grit marks"   Make sure you are using a high-quality paper.  The #grit isn't the only thing that matters.  The uniformity of the grit is important also, and any rogue, oversized bits are going to make a mark that's bigger than it should be, and extremely difficult to sand out with the next higher grit.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

3. 
   UncleDunc | Nov 16, 2004 02:10am | #4

   If you can use a sander, it makes a huge difference in fatigue and productivity. But you do probably have to worry more about technique than when you're hand sanding.

   If you can wet sand, generous quantities of whatever liquid go a long way towards preventing or delaying loading up.

   Depending on what you're painting, curing it in a low oven hardens the paint, which means the scratches at each grit are shallower.

   Don't push real hard. Let the abrasive do the work. More pressure equals more heat equals more finish softened and stuck to the sandpaper.

   Don't try to wring every last second of life out of the sandpaper. Your time is probably worth more than the sandpaper. Change to a new sheet while the old one is still cutting. When I was sanding steel with silicon carbide paper, I found it would cut like fury for about 50 strokes. It wouldn't be economical to change paper at that point, but neither is it economical to keep going till you're burnishing the work with the worn nubs of the abrasive particles.

4. 
   jazzdogg | Nov 16, 2004 03:35am | #6

   When dry sanding, I prefer to use stearated open-coat aluminum oxide. I always keep a brush or vacuum cleaner with brush attachment handy when I'm sanding. Brushing the surface of the work, and the sheet abrasive, to carry away the waste.  It's important to remove all traces of one abrasive before moving to a finer grit.

   Good luck,

   -Jazzdogg-

   Whether you think you can, or you think you can't, you're right.

5. 
   DavidSorg | Nov 18, 2004 12:44am | #7

   You don't say either way, but it sounds like you're using the papers dry, which makes a huge difference. Anything (in my opinion) above 320 grit should be used wet only.

   Assuming a near pristine surface finish, with only some brush marks or a little orange peel, and maybe a drip or sag, I would use 400 wet only lightly; just trying to level the tops of brush marks, for example. Don't try to get your entire surface to an even 400 grit sheen; there should be lots of shiny (untouched areas) when you're done with  the 400. If the surface is so bad to need 400 everywhere, level it with 320 and apply one last thin coat of whatever you're using. The job of the last finish coat should be mainly to fill in the valleys of the 320, not get a surface build which was the job of earlier coats.

   Anyway, use the 600 wet over everything, always using a sanding block where possible. When you're done with 600, almost the entire surface should have a smooth, low satin sheen with a few shiny dimples here and there. Then switch to 1000 or 1200 grit, doing the same. A few small shiny spots should be all that remain.

   Finish up with 1500 or 2000 grit, then a rubbing compound, and finally a polishing compound.