When do you stop? 1200? 1500? 2500?

You know when you've done enough when you consider polishing with toothpaste!!! On a more serious note I find 'Tetrosyl' Rubbing Compound to be superb at polishing hulls and foils. If your local Motor Factors doesn't stock Tetrosly then maybe enquire about an alternative rubbing compound as I'm positive you wont be disappointed with the results.
For general hull cleaning I use a caravan/boat cleaner, it can get rid of light marks whilst at the same time provides a very light 'T' cut to the Gel coat. There's also very little detergent so no problems with sliding about afterwards on the gleaming hulls <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

My arm wore out, so I finished with 2000 and a very light rubbing compound. Not perfect, but it's all I'm doing! <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

Go to Northern Tool and you can purchase a buffer for about $60. Then use rubbung compound, then go to polishing compound and finish with a silicone car wax. This will give you awesome results.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200319667_200319667

Milwaukee 9" grinder with a 3M buffer head. Then just a cleaner wax with a foam pad. Your arms will still be sore though, that thing is a brute to hang on to.

I have a big honkin' grinder, but prefer to wet sand. Better feel, less dust, less chance of cutting through the gel coat.

btw- I rolled the gel coat on. It was work to smooth it out, but not as bad as I had feared. From here on out my rule is: white boats and gel coat. NO PAINT!

bbtw- I applied the gel coat on a very cool day, 63 degrees. The temp. prompted me to use more hardener than was necessary, causing the gel to "tack" before I was ready. Next time, experimenting with the hardener should reduce the work significantly.

Use the grinder with the buffing pad to work the wax. I use Mcguires cleaner wax in a paste. The boat looks brand new in no time. No dust really.

If you liked those results then you should thin it with acetone and spray it on. Then you will only be polishing the work you've done.

Next time, I'll try spray.