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cruising Level 2?


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I'm going single handed cruising (but only for a few days) on Thursday as the weather up here in the land of Auckland looks bloody good!!!

Have to be back monday to get hull checked for osmosis 😟

And then go again for a few more days. 

Who is heading out? Might be more crowded out there than ever at this time of year!

Fisherman with time on there hands, boaties just desperate for a change etc...............

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I'm going to support local business by going and spending my life savings on boat and marine related stuff in the first day of L2. It sounds like retailers are expecting things to be heaving.

Of all the thing I can get in my first taste of freedom, I'm going to collect new engine anodes and a spare impellor! My 6 month engine service is overdue due to the rona. It might sound odd, but I haven't got my head around actually being able to go boating any time I want yet. I feel the need to ease myself back into boating by spending boat money and doing maintenance. Only then could I possibly conceive the idea of just sailing the boat...

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1 hour ago, Black Panther said:

Would like to pop out again next week but for the first time in 3 years struggling to find a suitable tide to escape the river 

Can't you just go out on the high tide?

I've got a well calibrated tide programme if you want me to tell you what will work for your draft? I haven't gotten stuck for ages, promise ;-)

 

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You mean there are some low highs next week?

Hmm, I see your problem. Have you thought about going on a diet? A bit of weight loss might reduce the draft a bit ;-)

I've checked my little tide programme. I record the depth and time every time we cross the bar, and cross check it against what the programme predicts, so it is fairly reliable. I've calibrated it with some percussion hydrography once or twice, but haven't carried out a calibration for several years now. The bar is at 0.6 m below datum.

For this Sat 16th, HT is 14:36 and 2.38 m (at Weiti River entrance, not Auckland) note Metservice says 2.5 m so a slight discrepancy there.

My programme predicts at bang on high tide you will have 0.28 m clear under the keel. With the datum of -0.6 plus 2.38 = 2.98 m of water. If you draw 2.7 m, you are left with 0.28 m clearance.

Some caveats with that, is that my sounder doesn't go to more than 1 decimal place, so there is at least a 0.1 m margin of error on my calcs. You also need to consider climatic conditions, which I don't allow for. Big highs push the water down, so less depth, but the main issue, if there is any bouncy bouncy on the bar you need to allow more safety factor. We hardly ever get bouncy bouncy, only when the wind blows from the East... like it has for the last week... You would also want to have some confidence about your actual draft.

I'm not sure how prone your boat is to moving in the bouncy stuff, ours does, but we are literally half the size of you. Cross the bar with no clearance in any bouncy bouncy is a completely different proposition to scraping over in flat water. You don't really wont to land on the keel in a wave trough.

If its flat water, you should be fine to cross between 13:15 and 15:55 on the 16th. I've adjusted that to give a 0.1 m safety factor, but you will still only get 0.1 or 0.2 m clearance around the high tide itself. In saying that, it looks like its going to be in the east or SE for the rest of the forecast period at the moment (7 days).

It is a fairly soft bar, so it doesn't hurt if you hit it. Last time we did it properly (tried cutting the corner on the Arkles side) our keel just dug a hole in the mud. You might fall over though with your draft.

If you want to try sneaking out on any other day, let me know and I'll run the numbers.

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My new boat draws 2.15m and I will be keeping it up the river just past the stillwater wharf. Pretty keen to hear more of your thoughts on the bar depth and the best way to go. 

I am delivering it down this weekend.

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8 hours ago, B00B00 said:

My new boat draws 2.15m and I will be keeping it up the river just past the stillwater wharf. Pretty keen to hear more of your thoughts on the bar depth and the best way to go. 

I am delivering it down this weekend.

All you have to do is stay behind BP🤣

 

It's a good idea to visit the entrance at low tide in a dinghy and carrying a long bamboo pole.

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10 hours ago, B00B00 said:

My new boat draws 2.15m and I will be keeping it up the river just past the stillwater wharf. Pretty keen to hear more of your thoughts on the bar depth and the best way to go. 

I am delivering it down this weekend.

Another boat? don't you have enough already?

The kids are on the laptop with the tide programme at the moment, and as that is keeping them quiet and their mother happy, it is def not worth me trying to get them off it. I'll check the times for Sat and Sun later. The bar is 0.6 m below the tide / chart datum, so if you have an app that gives you height of tide at a particular time, its fairly easy to work out. the depth at a particular time is your tide height plus 0.6 m. take off your draft and that will give your clearance.

The deepest water over the bar is easy enough to describe. There is a single outer (seaward) port hand marker post. There is another port hand post and a starboard hand post opposite each other, these are inside the bar. If you line up the outer port post with the inner starboard post, and go fairly much directly between them, you will be over the deepest part of the bar. It is easiest to see on a calm day with an outgoing spring tide. The fast water scours out the bar, so shows the deepest part. It easier to see the fast water when its calm. Conversely, if there is good wind over tide, the bigger waves are in the deeper part.

After that, go just to the south side of the two moored boats you can see just before the bend. One is a heavy motor cruiser, Endeavour, the other an ocean going trimaran. The bearing is about 290 or 300 true, but I can check if its important.

Going from the bar to the first bend, a sandbank runs parallel the whole way. It shelves quickly and is kind of hard, so don't wander south of your line.

Around the first bend is the Weiti moorings. That is fairly straight forward. At low tide there is the odd shallow spot on the South side, where the creeks fan out silt into the river.

Toward Stillwater above the Weiti moorings is pirate country, you' probably know more about that than me. I've only taken my paddle board up there. I've seen you out teaching the boys to sail while I've been paddling. Its a great spot at high tide. I usually see one stingray, and often see up to three. So many fish its like paddling in an aquarium.

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I did consider replacing the mark on the outer pile with reflective tape. I could sit at anchor at Atkles and occasionally hit it with a spotlight.  When it stopped winking back I could head up the river.

But haven't done it. 

 

 

Yet

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2 minutes ago, Rehabilitated said:

Get with tech. A handheld deepth Sounder.

My Father first sounded the bar with a lead line in the dinghy at low tide, when he first moved the boat to the river. It is very difficult to have calibration issues with sticks or lead lines. Apparently they don't need firm ware upgrades and sh*t like that as well... ;-)

Tech can be good, but there is nothing like hands on knowledge and mark 1 eyeball familiarity, especially if you are going to be crossing the bar regularly for a number of years.

Most people use a rule of thumb or something, like 3 hrs either side of high tide etc. I've gone to the increased detail so I can push the boundaries a bit more. When the tide is running, 10 mins either way can give a substantial change in depth.

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Most modern sonars can do 300mm increments. Some can do 100, but they are pricey. Easiest way to calibrate is use use a stick or a leadline. Once set once, they don't really change. But many owners dont know how far under the surface the transducer is, and some dont know if its reading from the surface or the depth under the keel, or from the transducer! Its pretty easy to set up, and if you have a reasonably late model Navico (Lowrance, Simrad, or B&G)  you can make your own accurate charts every time you go in or out - this video is a bit old, you can do this on the cmap charts as well now...

 

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12 hours ago, B00B00 said:

My new boat draws 2.15m and I will be keeping it up the river just past the stillwater wharf. Pretty keen to hear more of your thoughts on the bar depth and the best way to go. 

I am delivering it down this weekend.

Tease...

 

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15 hours ago, Rehabilitated said:

YES.

Sorry Rehad, I'll expand my question a bit. This hand held sounder sounds interesting, and not too expensive at $200. I currently need to replace my transducer, do you have a link to this hand held one so I can check it out?

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Booboo,

Times at the bar for drawing 2.2 m

Sat 16th 11:25 to 17:54

Sun 17th 12:15 to 18:55

Not that the depth will change 0.1 m 15 mins either side of those times, so allow a bit of a safety margin.

What sort of keel is it? Another deep bulb on an old 'family cruiser' that can send at mack 2 again?

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