Saturday, August 31, 2013

More adventures

Back in June we had a nice sail around Maumee Bay, and coming back we had to beat into the wind.  Unfortunately the knots in the loop of line securing the sheet block to the main sprit boom came undone and we were left with an out-of-control mainsail, just as the wind was becoming brisk if not fierce.  Not to be deterred, I left my friend Michael at the helm and grabbed the end of the boom with my hand.  Every time he tacked (and it was several times) I changed hands and sides and held on for dear life as the boat bucked the waves.  The virtues of two masts with smallish sails and the gentle behavior of the rig were apparent.  We made it to the ramp with no trouble.  Until, that is, I tried to bring the trailer around for retrieval.  I looked left and right, started moving out of the parking spot, looked behind to check the trailer, and then bang!  I had a low-speed collision with an SUV that was not supposed to be there.  He had snuck around from the wrong side of the parking lot behind two parked trucks, zoomed along and ended in the wrong place at the wrong time.  Anyway, a waste of time and money and a nuisance but no harm done.

The leak, meanwhile, was still there, if much reduced.  I found it, or so I thought: a small void in a scarf joint on the boat’s starboard garboard (right-side bottom piece doesn’t sound as good).  I dug out some wood that seemed soft, then filled it with epoxy filleting compound.  I also retied the loop of the mainsheet block nice and tight and checked and tightened the other three (one for a sheet block and two for the halyard blocks).  Then we went sailing again in August.  This last time we had no parking lot scrapes, but a few other ones.  

Going out was fine, like the last time.  With a fair wind it took us no time to sail out to Maumee Bay State Park, where we beached the boat and had a quick swim.  I say quick, because the algae bloom was pretty bad so it was neither pleasant to look at nor particularly safe.  On the way back the same thing happened: we had to beat into an ever-stiffening wind and whitecaps.  As the wind got very strong, I was keeping a wary eye on the mainmast that was bending quite a lot.  I said to Michael, “you know, it would be really bad if the mainmast failed.”  As soon as I said it he pointed out that the mast was starting to delaminate at one point above the foredeck.  I did not bother to check it myself: I gave the helm back to him and dropped the mainsail, hoping to get in just by the mizzen, or by rowing if that didn’t work out.

Now I know what happens to a cat ketch with no mainsail.  It would not tack so we had to wear (turn through a gibe).  A sprit boom is much gentler than a regular one in a gibe, but still.  One time the boom tip knocked Michael’s hat off his head and he steered us back so I could retrieve it with the boathook:  a flawless maneuver that gives me some confidence that we can deal with a man overboard situation.  But every time we wore and gibed we lost whatever way we had made and were not moving.  So I decided to drop the mizzen sail, unstep the mizzen mast and row in.  In my haste I let the yard down too quickly and it hit me on the forehead, causing a scratch that bled quite a bit (for a short time fortunately).  We then rowed in the teeth of the waves and wind for over an hour.  It was incredibly hard work we but made it back for a well-deserved picnic.

So now what?  In designing the masts, I had not taken into account the fact that a lugsail is attached to the mast in only one place, at the very top where the yard is secured with halyard and toggle.  Hence the very noticeable bend.  The bending stress clearly found the weakest spot, a scarf joint on an outer layer of the three laminated together.  Interestingly there is much less bend and no problems so far with the mizzen mast.

I first considered two options: making new aluminum masts, or wrapping the existing masts in two layers of fiberglass tape.  Both are costly and would require a lot of work.  Fiberglass would also increase the weight, and for aluminum masts I would need to learn new skills and get new equipment (a pop riveter, say, as well as new hardware).  I therefore settled on a partial approach: only reinforce the places where there are outer scarf joints (two per mast) with fiberglass tape.  Bending per se is not a problem: it actually helps by flattening the sail and spilling wind in when it blows hard.  So I will try again and play it by ear.  If this is not enough then there are plenty of other options.  Aluminum masts won’t look as nice but are stronger per pound of weight.  And much as I hate to give up my one-of-a-kind rig and beautiful hand-made spars and sails, the boat can always be re-rigged.  A gaff sloop would be a good candidate.

Another thing I decided after all these adventures is that having an auxiliary engine is a good idea.  I will therefore accept a colleague’s offer of a very old, light and low-horsepower outboard.
But I hear you say, what about the leak, is it vanquished?  Alas, not quite.  Every time I tinker it gets smaller (down to about 1.5 liters/quarts after more than five hours) but hasn’t gone away yet.  I think there is a tiny void at the aft end of the centerboard slot.  I hope this is the end of it.

Until the next report.