Re: slow polishing buffer for wet sanding
You start with the grade paper you need to start with, not what you want to start with. If you have scratches so deep that you need 240 then use 240. If it needs 180 then use 180. If its just faded and you don't have a scratch or gouge anywhere then maybe you can start with 400 or 600, maybe even finer paper. The point is that there is no set starting point - it is dictated by the job you have in front of you. If you have no scratches there probably is no reason to sand it at all. All rubbing compound is not created equal, some is much more agressive than others. Take advantage of that.<br /><br />I can tell you this though, it will be a lot faster to sand it with 240 and then sand it again with 400 grit than it will be to just start with 400. It will also be a lot less effort over all and its pretty likely that you would do a better job overall.<br /><br />By the way, those abrasive cleasing powders will leave a finish roughly equal (no pun intended) to about 300 grit paper, maybe a little finer.<br /><br />Also,don't worry too much about sanding through the gel coat. It doesn't just happen with one swipe of the sanding block - you can see it comming and quit. Besides that, if the scratch you are trying to sand out already goes through the gel coat then you need to do a repair, not be playing around with sanding the finish. If the scratch does not go all the way through the gel coat then you do not need to sand all the way through the gel coat to fix it. Avoiding going through the gel coat is just a matter of paying a little bit of attention to what you are doing - no kidding.<br /><br />Last thing, and I will not be so diplomatic as the others have been. You would have to be a damned-fool, and soon to be a dead-damned-fool, if you try to wet sand a boat, or anything else, with an electric appliance not designed specifically for work with water. If you want to wet sand with power use air tools. The other day I saw someone comment, in response to a similar question, that he had wet sanded his boat using a 'random orbit' sander and a GFI outlet. It was the single most irresponsible and dangerous posting I recall seeing. It was like recommending Crack for a child's toothache - guaranteed disaster right around the corner.<br /><br />Thom