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Tangalooma

Laptop failure has kept me away from these pages for a few weeks.  Its now going again thanks to Tim – he sold me an old – but working – laptop identical to mine, so I scavenged the best bits of each and now have a pretty good, but old, iBook.

My brother Greg has been on board for the last few days and yesterday we sailed to Straddie – Deanbilla Bay was too jiggly and we moved around to Myora for last night.  And now we are at Tangalooma – it was a great sail here from Myora. The anchorage here is also a bit rolly – the wind is more from the south than I expected.

For those interested in the electric motor and technical stuff read on.

One of the attractive features of electric motors is that, when sailing, the motor spins as the water flows past the prop, and power is fed back into the batteries.  In practise though the speed at which regen occurs is too high.  Today the regen peaked at about 8 amps, at a boat speed of around 11 knots.  Regen starts at a little over 5 knots.  At 5 its zero.  At 7.5 knots its about 3 amps.  between 9 and 10 knots it kicks in about 6 amps of power.

The motor well is open at the bottom and at speed over 9 knots the water really boils around in the well.  So the flow over the prop is anything but streamlined, and so I think there is scope for improvement by attaching a panel to the motor which will nicely seal the bottom of the well, and create a smooth streamline shape above the motor.

At speeds over 10 knots it sounds like cavitation – or some form of aeration – is occuring and the efficiency would not doubt be suffering.

At start of sailing the engine batteries were down 5 amhours from anchoring the night before and getting off the anchor this morning.  The sail to Tangalooma – or at the last hour or so when speed was high enough – put back most of this deficit.  But anchoring was troublesome and we did it three times until i was satisfied with it.  That drew power out of the engine pack so they are now down 15 amphours.

This is my cue to fess up – I bought a cheap genset to top up the batteries until such time as I get more solar power, and improve the regen. Until then I will be be using – gasp – fossil fuel to satisfy my need for power.

Thats all for today.  cheers

–chris

 

 

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Moreton Bay

Since leaving the river I’ve stayed in Moreton Bay and am now parked up in Krummel Passage between Russell and Karragarra Islands. Deb left a few days ago and I am now back on projects again.

There’s lots to do – the new boom demands some re-routing of reefing lines and other sail control lines and tackle. Today I’ve been wiring in an automatic system for charging the engine batteries whenever the house batteries are full.  This will allow the excess current to overflow into the lithium batteries.  Until now it has required manual switching.  I’m also progressing on installing a watermaker.

 

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Escape from Monty’s

A new year resolution is to blog more than I have been.  So here we go… 

On the first of January I left Monty’s boatyard and the Caboolture River – at last!

I went to Monty’s in May, ostensibly for about two weeks, but an avalanche of projects for maintenance of both the boat and me has kept me there until now.

One of the main troubles was ongoing teething problems with the electric motor and controller. And so it was with trepidation that we prepared to go down the river and out into Moreton Bay, with many hopes pinned on the motor working smoothly…

On board was Deb, who is staying a few weeks, and other friends Steve, Miki, Sean and Eric who came along for her first outing with new sails and motor.  I planned to arrive at the shallow part of the river at low tide to cross as early as possible on a rising tide.

I gave the signal to Steve to be ready to drop the mooring rope and turned throttle.  Nothing.  I tried the Microsoft technique of switching it off and on again but that didn’t work either. Bugger.

Monty’s syndrome still has its tentacles around me.  I checked a few more things.  Still nothing.  Lets try a process of elimination.  Check that there is voltage getting to the motor…  Steve pulled apart the Anderson connector so I could apply the multimeter and noticed the terminal in the connector was loose. We put it in place and hellelujah!  It works again.

Drawing less than 10 amps we motored at about 2 to 3 knots in the quiet of first light, until we got to the shallows.

As well as the main electric motor, I have a back-up trolling motor, and we used this to cross the shallows.  By lifting the centre-board and rudder, she draws about 2 feet. We did ground for a while, and we stuck for an hour or so until Steve suggested using the trolling motor to pull her out backwards.

That worked a treat and we negotiated a mile of the shallows backwards – the channel was too narrow to turn around now that there was a current of about 1 knot.  The trolling motor can pull her along at 2 knots – and therefore only 1 knot against this current.

Once out into Moreton Bay we hoisted the new sails – wow – they look so good.  They are brilliant white spectra cloth with carbon tapes along the load paths, and carbon reinforcing patches. The black on white looks really dramatic. And they set beatifully. We cross Deception Bay and turn south to Redcliffe. The wind is picking up from the zephyr as we left the Caboolture River and she’s going to windward at 7 to 10 knots.

The motor works as a generator when sailing and this is the first chance to test this.  At 7.5 knots its producing 3 amps of power.  I was hoping for more but in a day’s sailing of say 10 hours this would produce a useful 30 amphours.

We dropped the visitors off at Redcliffe Jetty.  By this time the wind was gusty at about 15 to 20 knots, and the motor worked nicely to bring her up to the jetty against this wind.

Then Deb and I sailed just under jib downwind to Deanbilla Bay on Straddie for a well earned rest.

Well, it was meant to be, but you know what sailing’s like.  Never a dull moment.  I’ll tell you about the dragging anchor and other adventures in my next entry.