Monday, October 05, 2009

Never In The History of Mankind

Chesapeake Bay
NoLL

Never in the history of mankind has so much time effort and money been spent to accomplish to little. OK, so I exaggerate the story of our deck paint projects a bit, but still ...

The problem is the non-skid areas of the top decks on Tarwathie. The hull has built-in non-skid areas with dimples of fiberglass that stick up. They are fine except for paint preparation. If one tries to sand the dimpled surface, the only thing accomplished is to wear down the tops of the dimples and the valleys remain unsanded.

Three times before in the past 4.5 years, we set out to repaint the decks. We used Interlux Topside paint which is supposed to be right for the application. It's expensive, costing $45 per quart at West Marine. In each case we did what we thought was adequate preparation and applied two coats.

The results have been dismal. In some places the paint flaked off after a year. In other places it turned dark and dull. Worst of all, it has not been durable. We have several places where the paint wore through all those layers of paint to bare fiberglass.

I resolved to fix it once and for all in our fourth try. Last year in Vero I researched the problem and selected Duraback 18 deck paint. It was advertised to be non-skid and very durable; just what the doctor ordered. It is the kind of stuff used on gang planks, stair steps, and working boat decks.

Well, the Duraback proved to be too much and too little. It went on very thick. It made a finish that is very non-skid, so much so that it hurts to walk on it with bare feet. It should be very very durable. However, it flunked on color coverage. We were overpainting dark blue with light beige, and the blue showed through everywhere.

So for the fifth repainting, we went back to Interlux and painted through the pores in the Duraback. That covered the colors. One would think that the issue was settled. Right :) Wrong :(

I prepared the old surface using paint remover and then dewaxing chemical.

When Libby went to remove the masking tape, she found that the tape lifted up all the paint with it. It seems that it forms a 1/8 inch thick rubber-like layer that is extremely tough. Where this layer covered both deck and masking tape, and when we pulled the tape up the paint-to-paint strength was much stronger than the paint-to-deck adhesion.

Libby is a great companion and a willing and hard working crewman. However, she does have a few quirks that seem almost obsessive-compulsive; quirks like picking at a scab. She started picking at the paint where it had separated from the deck. Libby called out for me to come look. It took me 5 minutes to get there. In those 5 minutes she removed almost 2 square feet of the Duraback and Interlux. When I got there and saw what was happening, I yelled at the top of my lungs STOP. But the damage was done. See the picture.



I learned that one needs to cut the paint layer with a sharp knife or razor blade to make a seam between the painted deck and the edge of the masking tape. After the cut, the tape can be lifted.

Did we fail to prepare adequately yet again? I'll never know for sure, but I suspect that the strength of that Duraback layer to tearing will always be stronger than its adhesion to the deck and resistance to lifting.

So now, we face a sixth attempt at painting to repair the ugly spot. I'm too cheap to pay another $150 for another gallon of Duraback to repaint that spot, so any remedy from now on will never ever match the surrounding deck and will remain forever as an irritating reminder of our stupidity.

How could we have screwed up so badly? I can't think of a valid excuse. Lots of people successfully repaint their non-skid area with little or no trouble on their first attempt. I must admit that this is perhaps the the biggest example of incompetent bumbling that we've ever committed while on Tarwathie.

1 comment:

  1. Hi Dick and Libby,

    Tarwathie looks very sharp in your photo of her on stands in the last blog entry. You've gotten a lot accomplished!

    On the non-skid painting: My opinion is that to "properly" paint non-skid onto a deck, you first have to sand/grind off the "factory" non-skid that is molded into the gelcoat. Then you start with a smooth surface, tape of the areas you want to be non-skid, and paint them with Interdeck or whatever product you choose.

    I've never found painting over molded in non-skid to work.

    I missed your logs during the hiatus, but figured you were bushed from long days on the hard, working. Nice to see the new entries :)

    R.

    ReplyDelete

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