Monday, August 19, 2013

Sand ...

There is sand falling out of what looks like a hole in the bottom of my boat. Sand? This cannot be a good thing.

I should have left well enough alone. The area around the keel joint had been ground out and sanded back to solid fiberglass; but the the bottom edge of that fiberglass was loose and there still appeared to be a minute trace of moisture. The mechanic in me was curious as to the origin of said moisture, so the rotary file went to tracing a track up from the loose edge. Just a couple of inches above the keel joint it plunged through into a void and thus appeared the flow of sand.

"This," I thought out loud, "cannot be a good thing."

Replacing the rotary file with a cutting disk I very carefully cut a square of very solid fiberglass aft, paralleling the keel joint. More sand flowed which was clearly a component of a block of material that filled the void between the flat top of the lead keel and the curve of the fiberglass hull; a void that was enclosed behind a skirt of fiberglass flared off the hull and overlapping the top of the keel. Mystery ... the top end of the block block felt like concrete. Could the sand really be deteriorating concrete? The chunk looked like concrete. When hit with a grinding disc it produced a small dust like cloud that smelled like concrete. There is certainly a lot of sand in concrete.

Concrete, in my Tartan?

An assembly of sailors gathered around the boat to gaze at the mystery. As they did I had already decided
two things. Number one was, as bad as this appeared at first, we were once again looking at a cosmetic repair. The keel bolts were fast, the hull unblemished and unbreached, and the keel still a solid block of lead holding up a boat. Number two was that this really was concrete, albeit cheap concete; more like the capping stuff put on the top of foundation wall (basically a mixture of limestone and sand). The assembled agreed though there was some debate as to the proper stuff to use to fill the void to facilitate the fiberglass repair. Some optioned a quick set concrete filler, others fiberglass mat. I've decided that West Marine epoxy filler will be the choice, a choice supported by an Internet friend to whom Deb sent some pictures, a friend who just happens to be an ex-aircraft mechanic and who is currently resupplying the cruising kitty by running a boat repair facility. (It is good to have friends in high places!)

So, though I added another day of work I didn't need to by opening up the void to see what the what, at least I know what the what is. Concrete ... apparently Tartan decided to fill this below-the-waterline void with something cheap and heavy. I wouldn't have thought the words "concrete" and a "Tartan" would go in the same sentence; but nothing in the marine industry surprises me anymore. My "higher end" boat builder poured a water soluble sand mix into a void below the water line. The void got breached, moisture oozed in, some of the limestone slowly melted away, and sand fell out the hole.

Fix it, fair it, clean it, paint it, throw it in the water. With just a bit of luck we will start putting color on the bottom tomorrow. Seeing Kintala with a clean, painted hull will go a long way to have me thinking we are actually pulling this off. Right now I'm just tired and sore, looking at another day of work and wondering when the "throw it in the water" day will arrive.

3 comments:

S/V Veranda said...

For a retired guy you sure are working a lot....

TJ said...

You know, another 10 hour day with my head wrapped in a towel to keep the knats out of me ears, breathing through a mask to keep them out of my nose and mouth, grinding away, laying down fiberglass and filler, then grinding some more ... with maybe two more days to go before the bottom is done and painted ...

... right now I'm thinking pretty much the same thing ... working for a living was easy.

Latitude 43 said...

I'm not sure how I would react to sand pouring out of my keel. Maybe from all the bottom paint exposure over the years I might have just started drilling random holes in the hull while laughing and crying.