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Phil's Guide to Sanding Preparation for Bare Wood

Part 1 – Preparing the Surface
The appearance of a finished surface depends more on smoothness than any other factor. Smoothness also plays a very
important part in the durability or longevity of the coating, as a rough surface will have small sharp edges and thin spots in the
coating that is applied to it. These spots will show a premature “burn-through” or wearing due to insufficient coating
thickness, so it’s necessary to get the surface sanded smooth before any finish is applied.
Any wood that is to have a finish applied to it must be sanded smooth. This is a process that seems to be greatly
misunderstood. We hear people saying “I can’t sand my wood, too much will be lost”. This is a common misconception. Yes,
you will lose some wood thickness, but it is absolutely necessary. No, you won’t lose too much. Maybe you will need to reglue
a couple of thin plugs, but that’s easy. We do it all the time.
Equipment
Sandpaper is sandpaper. There are some brands that last longer than others, but don’t get hung up on this. All good boat and
hardware stores carry decent brands. What you need are 3 different grits- 80 grit, 150 grit and 220 grit. Get plenty of each.
Power sanders are necessary. We like to use Porter Cable random orbit machines for the heavy sanding. Both Porter Cable
and Ryobi make good machines for smaller areas and finer grit sanding. These brands cost a little more than cheap gear, but
they last a LOT longer, and they do a far better job than cheap junk, and the operator doesn’t get as tired. Worth every penny.
The Process- Bare Wood
This is a brief article, and if our description doesn’t make enough sense, then go to your library and check out a stack of books.
There are lots of good ones that take a lot of time to go into the basics, but relax- the important part is all right here.
Step One- Sand the wood COMPLETELY smooth
Start with 80 grit paper. Use the machines for everything you can, and hand sand the tight spots. Sand and feel the results with
your bare hand as you go, and keep using the 80 grit until the wood is completely smooth with absolutely no high spots. Get
rid of the dust with a small broom or an old paintbrush.
Step Two- Stains in the Wood
If your wood has black stains from weathering, now is the time to get busy with the teak cleaner. Use any good two-step teak
cleaner to remove excess oil, stains or discoloration from weathering. For other wood types, use a mild one-step wood cleaner
if required. Follow the manufacturer's instructions carefully and fully rinse to remove all residue. Allow the wood to dry
completely for a minimum of 24 hours.
Step Three- Resume the Sanding Program
After sanding with 80 grit, and whether or not teak cleaner is used, what you have now is smooth wood with small gouges in it
from the 80 grit sanding. These must be smoothed out or they will show through the finish, and this is what the 150 grit is for.
Simply repeat the sanding process using the finer grit, sanding and feeling with your hand as you go. You will notice a big
difference, and the start of a silky smoothness.
Step Four- The Finish Pass
You probably guessed this one- sand everything again with the 220 grit. This is to reduce the gouges left by the 150 grit.
All sound like a lot of hard work? It’s really not. Matter of fact, it’s less work to get this done right, compared to dealing with
premature coating failure. Proper sanding is not as hard as you think, and the results are very rewarding, not to mention
absolutely necessary!