Inga Nordic Folk Boat

A new look at canvas decks for wooden boats

Part 2: Go to part 1

Sister of oak on the sheer clamp where repairs were made to the clamp; this area is important to keep strong because the chain plate is going though the deck at this point.

Fibreglass had been applied over the original laid deck, of pitch pine, which had been fastened down with galvanized iron nails. The nails were almost completely rusted with their heads coming off with the fibreglass sheets, and the iron oxidization reacting with the tannins in the wood leaving the tail black mark of iron sickness.   Surprisingly most of the deck wood was in pretty good shape considering it was so wet.

Wood needs around 18 to 22% fresh water moisture for rot to occur, which this deck’s wood was sitting around, the heavy pitch in the wood was its great saviour.   Now at this point we could have left it, letting it dry out, repairing the few rot pockets, and refastening.   But after weighing out all the options, like iron sickness, and what the final plan was, we decided to remove the old deck entirely, which allowed us to address the deck beams, on which the end fastenings were also failing. Also a serious rot problem was found in the transoms, top plank and inner quarter knees, plus the stem end and breast hook that now, with the deck off, could be easily repaired.

New mast partner knees were installed where there were none before, this helps spread the rigging load	A new stem end of oak was scarfed on after finding extensive rot, which was also found in the breast hook where a new bigger breast hook was installed.

The owner has been coming over from Vancouver around 3 days a week to work and is learning how to repair his boat.  He has been taking on jobs he feels capable of doing, usually the jobs that are labour intensive. One of those jobs was wooding the hull (removing the hull paint down to bare wood).

A new aft floor timber was installed after finding extensive iron rot in the old one.

After he did this, I was able to easily survey the wood hull to see if any repairs were needed.  All the wood in the hull looked great except an area around the stem, where the plank ends were slightly coming away and could be pushed back into place with little effort.  I tried to remove the fastening to figure out what was going on, and to my alarm, the heads of the fastenings were crumbling away.  This was a tell tail sign that galvanic corrosion had broken them down, and this was also showing up in other areas of the boat.

The cock pit is getting 4 new ribs and 2 sistered ribs.
	The prop has been severely compromised be galvanic corrosion and will be replaced.

After trying to remove more, we found almost all fastenings in the plank end were severely degraded.  They may have been bought as a bronze, but just because its called a bronze does not mean the alloy was conducive to a marine environment, meaning the alloy recipe may have had zinc or aluminium in the mix, two components that leech out if the environmental conditions are right, causing the alloy to severely weaken (Manganese Bronze is 60% copper and 40% zinc). I explained to the owner, as we painstakingly removed all the plank end fastenings and replaced them with silicon bronze, that he was very fortunate to find this now and that if he was in a rough sea this could have opened up like a zipper and sunk the boat in minutes.

About 50% of the sheer strakes were replaced port and starboard, mid ship area.

Another important job has been replacing four frames and two sister frames in the cockpit, with steamed oak, bent into place, a job made much easier with the deck being out of the way.

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