SKIPJACK (Sea Devil)
Following up on Mondays story based on Dean Wrights photo gallery for Waikawa Bay marina, I was contacted by Greg Billington in regard to a photograph featured of his boat – the 33’ Baily built ‘Skipjack’. I’ll let Greg tell the story –
“You will see in the photo (number two above) that the mast is down, it is hinged because I formerly kept her in the Okahu Lagoon, which meant going under the Tamaki bridge. It is a new alloy mast, by the way, and considerably shorter than the former very heavy timber mast. On the occasion, some years ago that I laid it on its side in a beam sea crossing Bream Bay, I decided the timber mast was too much deadweight to bring back up! However, that the mast is hinged is convenient for a rather unexpected reason. I discovered that in winds around 20 knots, the new mast would vibrate. My first thought was to adjust the stays, but it made no difference. Then I learned about ‘vortex shedding.’ You may know that this can occur around any cylinder and in fact has caused the failure of even very large structures. At certain wind speeds, vortices form on the downwind side and create vibration. As it happens, it is easily remedied by doing a couple of turns of a rope or stay around the mast. In the marina I just lower the mast to the bow rail.
I’ve had Skipjack in Waikawa for 3 years now. Assuming that many Auckland boaties may not know too much about the Sounds, I thought some comparisons might be of interest. The Sounds comprise nearly 20 per cent of our total coastline – so lots of scope for exploring. However, it contrasts with the Gulf in several ways. First, it is adjacent to Cook Strait. Need I say more? On one occasion I spent three days in a bay because I couldn’t leave. It was not possible to see the other side of the Sound through the williwas. Another time I was alarmed by a crash and found my inflatable had been picked up by the wind and hurled into the stern. The slack painter was promptly severed by the prop and I watched with incredulity as the dinghy took off and literally flew for about 50 metres.
Then there’s the tides. It is a strange spectacle seeing enormous surface turbulence above depths of 50 plus metres, and for a Gulf boatie, being above 140m depth less than half a click offshore seems most peculiar. Then there’s the challenge of anchoring. Most boaties here rely on the network of club moorings because the magnificent hills of the Sounds, tend to go straight down. The Gulf is blessed with great bottom for anchoring. The Sounds are not! And finally, the water temperature…where I habitually dropped the pick in one of many bays in the Gulf islands and dived over for a decent swim, here, on a blistering hot day in mid-summer, one plunges in – and out! But the low temperature probably explains why good antifouling can go a couple of years and need nothing more than a soft waterblast. There are no goddamn barnacles!
But lest you think this is not a great place to boat, I include a pic of Skipjack anchored in Mistletoe Bay“.
LOTS MORE DETAILS AND PHOTOS AT THE LINKS BELOW
2014 WW Story (then named Sea Devil) https://waitematawoodys.com/2019/07/26/skipjack-sea-devil/
2016 WW Story https://waitematawoodys.com/2016/08/27/skipjack/
2019 WW Story https://waitematawoodys.com/2019/07/26/skipjack-sea-devil/
Interesting about mast vibration. But that’s why they fit a scroll to boiler chimneys
Thelma looking sad in Evans Bay. Wellington.
On Thu, 15 Dec 2022, 12:13 am waitematawoodys.com #1 for classic wooden
Is skipjack double diagonal?