November 26th, 2014
Now on Thanksgiving vacation, I took advantage of some free time to continue preparing the boat for topsides paint. After a brief discussion with the owner, the plans for the painting scheme were slightly modified. The boat's bottom paint would be totally removed, and the topsides paint application would extend from sheer line to keel, so no bottom paint to control marine growth. The owner intends to store the dinghy on "the hard" when not in use, otherwise the boat's bottom would be consumed with marine life eager to colonize every square inch of its bottom.
That blue streak along the bottom of the dinghy is the previous bottom paint application. My first task for this work session would be to remove the bottom paint, and bring this surface to fair condition, ready for finish coats of paint.
Removing the old bottom paint began with 40-grit pads on the 5" random orbital sander. The use of 40-grit pads may seem a bit much for the removal of bottom paint, but in actuality was appropriate due to the fact that the sander used is a finish sander and my touch was feather-light. The outcome was predictable and satisfactory.
View from the bow looking aft, after the 40-grit pass.
The starboard bottom, after the 40-grit pass with the 5" random orbital finish sander. The darker spots on the boat's topsides are the cured epoxy application used to fill gouges too deep for the primer paint to fair.
Next, I made the switch to an 80-grit pad on the 5" finish sander to take care of the balance of the bottom paint, and to bring the surface closer to its topsides neighbor.
Making a thorough pass with the machine, I then finished the balance of the surfaces by hand.
A shot of the starboard aft quarter after the 80-grit pass.
The final sanding pass was a 220-grit pad on the 5" random orbital finish sander. Just prior to beginning this sanding application, I water washed the previous application of thickened epoxy (micro-balloons). The water washing is meant to remove the amine blush that forms on the surface of cured epoxy, and requires removal prior to sanding to prevent contamination of the surface. With a bit of water and a Scotch-Brite pad, I quickly removed this amine blush and was again ready to resume sanding.
The dinghy bottom after sanding the topsides' filled areas and the bottom.
Next, I used as bright a light as I had to reflect gouges on the bottom. The dinghy's bottom may just of been the object of Sisyphus's affection - the number of gouges and scrapes across suggested "well-used." Using the light, I carefully made my way down the port bottom and up the starboard bottom, circling areas that required filling.
Just a couple of photos showing how I marked these areas to give further attention to.
It becomes easy to see the extent of the needed repairs across the bottom, these areas required greater attention than the primer coats could provide. The filler here is West System epoxy thickened with micro-balloons, and is easily sanded to bring the surface to fair.
The keel was looking ragged.
A closing shot, from the stern. Next step will be to water wash the epoxy fairing application, and then sand. Primer is just around the proverbial corner.
Total Time: 2 Hrs.
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