Wednesday, September 22, 2010

When the Wood Gets Soft....

... and this is a problem I had when I owned Nordic Belle (USA 105), All of a sudden you'll be sailing and the shrouds are all loose and you can't figure out why. Its hard to see from the deck, but once you become aware of this possibility it becomes something you check for all the time. It's half the reason I keep a pair of binoculars on board.
These series of pictures comes courtesy of Klaus Kahl of Germany.













The story goes like this - Klaus says that after a day of force 6-7 winds they came back to the dock with loose shrouds, looked up and saw why. The spreader mount fitting had moved almost 2 inches and well, that's not a problem you can ignore. They prepared wooden strips
ahead of time (Mass: approx. 600mm long, 85mm broad and 3-4mm
thickly), the thickness may not be to large, because they must be able
to be bent. The wood is north spruce which is slow to grow and is a stronger wood.
First the main fitting was dismantled. The bad wood is carved out and all of it must go.
It's important to poke around the wood of the mast at the fittings to check for softness and prevent this from becoming a more serious problem. Same thing can happen at the main halyard shive at the top, gooseneck track where the boom attaches to the mast, at the deck and the heel cup. This one was caught before the mast would have required a more skilled woodworker or worse, unfixable. One of the concerns is not making it too stiff and ruining the bend characteristics you want in a mast. Too stiff and you'll put more stress on a different part of the mast and you'll never get the trim characteristics you'll need to shape the main sail. Too bendy and another set of problems, so a lot of thought goes into the type of wood, size of the grains, how they are laid in. After the epoxy and clamps do their thing, the screw holes need to be bored out and plugged. You could use longer screws, but that isn't the smartest idea. That wood is more than likely bad there too and its best to replace it. Making sure the plugs are of a dry wood and the holes are dry too will prevent the same problem from occurring again.

In the end the job looks very well done and the mast is repaired for a relatively low cost. Better than shelling out the bucks for a new one! Don't forget to put the black bands in the right spot!!

1 Comments:

Blogger Wiley Muller said...

All Kinds of Junk,

I'm a Folkboat owner and the exact same thing happenend to me! I could have said it any better. I was out about 3 miles away from the dock and I saw cracks coming from the shroud bracket. There was about 10 knots of breeze and I had full sail up and a little child on board whose mom was throwing up over the side. Yikes! Anyway I struck the sails, motored home and had the boatyard take a look. Luckily after some serious surgery, they were able to do a similar scarf and get me back on the water to salvage August September and October here in Maine. I am slowly finding myself dreaming about coming to The Bay.....

10:37 AM  

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