Updated: Aug 28, 2020
1. Prep the Wood Sand any bare wood to 120-grit and no finer. This will give the primer good “tooth” to hold on and create the right base to start with. Clean all dust. I use TSP, but sometimes I run out and make my own solution. If you rub your hand on the wood and feel even just a little dust, then it is not clean enough.
2. Sand Your Primer Without a smooth base you can’t get a smooth finish. Use 220-grit paper or fine sanding sponges (I use 400 grit) to sand everything down once the primer has dried enough that it generates dust when sanded. Clean off dust will dry cloth. Touch with your hand to feel for dust.