Thursday, 21 May 2020

Sailing Performance

We left Marina Fonatur in Guaymas on the 4th of March, bound for La Paz, with a the new rig and modified rudder combination that was largely untested apart from a couple of short forays on Bahia Interior de Guaymas. These short test sails were encouraging in that Taiko's reported shortcomings were minimised if not completely eliminated.
Windward sailing performance has been greatly improved by the cambered panel sails. The boat now seems to point to weather as well as any other boat we have sailed and shows good speed, up to six knots, on this point of sailing.
The reported excessive weather helm appears to be completely eliminated. On our test sails we only experienced bad weather helm when the boat was over pressed with too much canvas. Generally, the boat was well balanced under sail and the helm quite light. She now hums to you with a gentle vibration of the tiller when properly balanced while sailing to weather.


Test-sail with other Sailors who where very interested, followed our project and never sailed a Junk


Tacking through the eye of the wind was satisfactory, we never missed stays. We were confident enough of her ability to tack to short tack up the narrow channel back to the marina. Subsequently, we got the usual, by now expected, comment from our Bermudan Rig guests; “ I would never do that with my boat”. That said, being a long keeled vessel she is still slow to get through the eye of the wind and having no head sail to back we are far from certain that she would manage a tack in strong winds with a short sharp sea running.
Our theory on the elimination of excessive weather helm is as follows:
  1. The distance between the battens on the fore sail was increased to provide a calculated extra 3.5 square metres of sail area.
  2. The cambered panels have their maximum camber at 35% of chord thus, we think, shifting the sails' centre of effort forward. Flat sails have their centre of effort right in the middle at 50% of chord.
  3. The cambered profile rudder, with plates top and bottom, helps to maintain laminar flow over the surface of the rudder. It may also be that the centre of effort of the rudder has been moved further forward.
Our reasoning is bit woolly, no doubt a naval architect could better explain. However, the modifications that have been done appear to work.
For the first thirty hours of the trip to La Paz we enjoyed brisk WNW winds that made for a pleasant sail that saw us reaching along at around seven knots with two panels reefed in both fore and main sails. We felt very pleased with our selves while enjoying sighting whales and a rapid, though a little rough, passage to La Paz. The maximum speed recorded by the chart plotter on this part of trip was 10.6 knots which was doubtlessly an instantaneous recording when we were pushed sideways by a steep wave. Never the less she was moving at very reasonable speed for a heavily laden cruising boat. The Monitor wind-vane self steering performed superbly in the short steep waves of the Sea of Cortez.
The remainder of the trip saw us intermittently motor sailing in light and variable winds until anchoring in Puerto Balandra for the night, not far from La Paz. We were pleased to be able to sail the last few miles and finally tack into the bay and drop anchor under sail while pointy rig crews watched incredulously while taking photographs. Incidentally, I wonder why junkies call bermudan rigs 'pointy rigs' when our sails are mostly pointed at the top!
The following day we motored for two and half hours against the current to La Paz where we met up with Sharron Beck the assistant manager of Whangarei Marina. We helped her set up for her presentation on behalf of Whangarei Marine Promotions Group that encourages cruising yachts to visit Whangarei for the cyclone season. This was before the Corona virus wrecked everyone's plans. Later we had dinner with Sharron at her hotel and had a very pleasant evening catching up with news from home. Next day Sharron took off to meet up with the Dutch yacht Tara, which we later met in Agua Verde and Puerto Escondido. The cruising world is small!

The two and half weeks we spent in La Paz were very busy with chores, boat projects and provisioning while corona virus clamp tightened around us. Initially we considered clearing out of La Paz to leave for French Polynesia but this hope was dashed as every country from Central America to New Zealand closed it's borders. We found ourselves obliged to remain in Mexico with our tourist visas expiring with their renewal uncertain. However La Paz is a very nice town and we enjoyed our stay. The Malecon, up-graded in recent years, is very pleasant to walk along. There are many sculptures and murals, the houses are nicely decorated. But we had so much else to do on board that we barely had time to enjoy it.


The Malecon of La Paz


Nowadays water can be difficult to come by in the Pacific and many islanders struggle with their water supply. Similarly, in the desert of Baja California and Sonora water is also difficult to come by. Town supplied potable water is often of dubious quality so we therefore decided to install the water maker we bought already in January. While this an expensive luxury I would not ordinarily consider it has proved, thus far, very valuable. We also spent a lot of time trying to get the SSB radio working properly we have only been partially successful in this regard. We also expended a lot of energy tracing and fixing water leaks, both salt and fresh. These turned out to be relatively easily fixed with a bit silicon sealant around the seawater strainer O-rings, we couldn't find replacements large enough, and the fresh water tank inspection plates. We now have a bone dry bilge.
We quit La Paz on our seventeenth day of our stay just before La Paz shut down more our less completely and the Navy began patrolling inshore waters insisting yachts remain in place. Yachts were allowed to make a sea passage but not cruise or congregate in groups at anchorages or beaches. We were glad to be moving again and very pleased we were not required to remain in one place like all our friends in New Zealand.
Overall we are very pleased with our comfortable new boat though we need to experience some heavier weather in her to gain complete confidence. Though not as easy to sail single handed as Tystie (previous boat) she is fun to sail, comfortable and sails well enough to make us proud. While our new sails need further tweaking, in my opinion, they seem to perform well and their imperfections go unnoticed by the admirers who call out to us in complementary fashion and take photographs as we pass by.

Taiko tacking into the anchorage. The diagonal creases reappear when the sails are hauled in hard to go to windward. I haven't worked out a cure for this yet.


Sailing off the wind, no diagonal creases. We welcome any suggestions from junkies and other sailing enthusiast
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More on sailing in the next post – Impact of Corona Virus.

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