Sanding procedure
 

While my engine was out of the car for rebuilding I repainted a portion of the inner fender that was damaged from master cylinder brake fluid leak. The surface was cleaned and sanded then painted by me. I did it outside in the sun and it was hot out. I shouldnt have done it this way but I did it anyway.
After I can sprayed it I checked the next day and its very rough looking. I probably sprayed too much and the heat didnt help either.
My question is now that the engine is in and everything is hooked back up how can I sand it to make it look better? What types of sandpaper and process would I use?
Can I wet sand it and how would I go about it?
Thanks,
Rick

Sure you can still sand it. 400-600 wet should be just fine. Maybe buy some black etch primer in a spray can to help seal out whatever is causing you problems before painting it again.

600 probably is best. Most likely the heat caused your issue. Painting in direct sunlight in most cases will cause unfavorable results, use the same paint procedure in the garage today and it'd probably turn out fine. Mask, mask, mask. irgoatmike

Rick, I can loan you my grinder if you really want to rough up the surface :D

If the surface is smooth but dull, you might get by with a Scotch Brite pad and a quick respray in the shade.

I would scuff it good, then wash it well with some Dawn dishsoap. Maybe then spray it with some black etch primer. You can buy it in spray cans.
I agree with goatmike. Be sure to mask it real well. Spray can find its way all over everything!