My boat has been a big pain but after looking for something in my budget for about 5 months with no luck its time to fix mine.

long story short... I made the mistake of taking my boat to an idiot to be "blasted" he was suppose to use bead or walnut. When I went to pick it up the jerk had used sand. My whole boat, console/livewell and all of the little parts of aluminum has the texture of 60-80 grit sand paper... i put the boat away for over 9 months because i have been so discussed with myself...

I purchased a makita sander and it works well but i used 5 sanding disc on one one side and the top of one pontoon (float box).

I am using 150 grit, would i save disc by starting with a rougher grit and working my way up? Is there a better tool to be using?
this pic is just to show the pontoon, it was before i had the boat blasted.

use a 100 grit and go slow, auto quality sandpaper not the brown stuff for wood.
if you need smoother after that go to a 180 and move it fast over the aluminum.
after the 180 you can polish it with white metal polish from a truck stop, its the coarse jewelers rouge and will put a mirror finish on it

Yea....what hoppy says. But you didn't say if you are wanting to bring back the aluminum shine or are you prepping it for paint? If you are preping it for paint, don't bother. Just use the Primer by Interlux or Petit and then top coat with either Interlux or Petit, Easy Poxy or Brightside...... A dramitic finish will be obtained.

I am just going to paint it. I test sprayed an area with the paint and two part primer that I got from alweld, the cans are not labeled but it is the paint and primer they used on their boats. After spraying the blasted aluminum it just felt like painted sand paper, so i sanded a 1 square foot area with the 150 grit, repainted and it look pretty fair.

I am just trying to figure out how to use less sand paper, i have an area that is maybe 18" square ready to paint but i am going through the paper.. If I started with the 100 grit and then went to the 150 grit would that help save paper? I wanted to find a 220 grit or even a 180 would have been find but i have not been able to find it with the firm backing and the hole in it for attaching to a sander like mine.

Shoot a PM to bazztex before paining that aluminum. He knows all the ins and outs of it...besides having to alodine it.

Thanks, I will send him the link and invite him to the thread.

That's why I said to use the Interlux primer. It is way thicker and will settle in the scratches and craters that the sanding and blasting has done. Once dry. You sand the primer down slick and it is a lot easier and cheeper to do than what you are try to accomplish by sanding the metal smooth.

ok so it is like an extra high built primer but for aluminum..

the whole reason i wanted to have the boat blasted was to keep from having to sand.. When I went to get the boat I was really speechless, He thought he did good until i asked him if he lost his mind...

Sorry for the long delay.. Use Scotch Bright Roll lok disc red medium and blue is fine.

http://www.mechanicstoolsupply.com/Abrasives/Surface-Conditioning-Discs/index.html