Barrier Coat: Hull Underbody

I have been trying my best to chip away at exterior projects before the cold wet weather sets in (soon).

Yesterday saw two layers of epoxy barrier coat go on the underbody (below the bootstripe). I detailed what is a barrier coat and why in this post.

The prepwork involved filling and fairing holes from the keel resin infusion (long time ago) and the edges of the “go faster” bits forward of the rudder. As for application of the barrier coat, it goes something like this:

  1. Sand the gelcoat with 40 grit. Enough to remove the top oxidized gelcoat and any remaining gloss. Waiving a 6 inch random orbital sander overhead is really fun!
  2. Rinse well with a garden hose.
  3. Do a complete wipe down with acetone, twice, change out the cloth frequently.
  4. Mask off any necessary areas (bootstripe)
  5. Mix well, the color part of the paint (40% of it is solids, so settling is very likely)
  6. Combine one part catalyst with three parts color and mix well
  7. Let it “induct” in the pot for 20 minutes
  8. Roll on with a thin knap roller. Cut in necessary areas with a bristle brush.

Additional coats may be applied without sanding within 6 months of the previous coat.

Underbody sanded.

First coat of grey paint.

Two coats were applied. First one grey, second one white.

There are small unfinished areas around the thruster tube, which still needs some fairing work (later).
More coats will be applied before anti-fouling paint.

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