Any painter will tell you that proper surface preparation is essential for a good finish. Practical Sailor’s  step-by-step guide to repainting a hull includes a “Primer on Prep” that covers all the major prep-work steps (see PS August 2009, “DIY Topside Paint Test: Two-part Linear Polyurethanes Face Off”). We have also compared the various fairing compounds (see PS August 2017, “DIY Filling and Fairing”).

The random orbital sander spins in an elliptical pattern to minimizes swirl marks.  For heavier work, you’ll need a dual action sander or a more aggressive tool
(see PS April 2014, “Digging into Bottom Paint Removal”).

1. 1. The dual-action sander operates in random orbital mode for fairing and sanding, or in rotary mode for heavier work.
   2. The Fein vacuum sanding kit is the same used by the professionals at Casa Rio. You can also build your own do-it-yourself vacuum system using an ordinary shop vac, a five-gallon bucket, and a random-orbital sander (see “Dustless Sanding,” April 2016).
   3. The yard crew introduced us to the effectiveness of 40-grit wire Mirka Abranet mesh disks. Practical Sailor has conducted a variety of tests on abrasive papers and sponges (see PS July 2006, “Hand Abrasive Round-up”).