Reply
 
Thread Tools Search this Thread
 
Old 10 August 2009, 18:21   #11
Member
 
Country: UK - England
Town: Dartmouth
Boat name: Puffling
Make: Avon Rover 3.4m
Length: 5m +
Engine: Mercury 15hp
Join Date: Jan 2002
Posts: 387
Send a message via MSN to badbaws
Powertrim..

That is what they invented powertrim for..
__________________

__________________
Advanced Power Boat Instructor
badbaws is offline   Reply With Quote
Old 10 August 2009, 19:11   #12
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
Quote:
Originally Posted by BrAinZ View Post
Thanks for the posts so far.

So what depth on your gauge would make your concerned?

10ft, 6ft, 3ft ?
Depends what the draught is on the boat....
__________________

__________________
chewy is offline   Reply With Quote
Old 11 August 2009, 02:28   #13
Member
 
Country: UK - Channel Islands
Town: Jersey
Boat name: Archangel
Make: Ribcraft
Length: 6m +
Engine: ETec 225
MMSI: 235063789
Join Date: Sep 2008
Posts: 1,005
Shallow water

Shallow water is a way of life here in the Channel Islands. My depth sounder can read zero and I'll still be afloat. I use the boat hook-over-the-side technique described above all the time. Maybe one of those new-fangled forward-looking sonars is the answer. By the way, don't go to Mont St. Michel if you don't like the idea of shallow, murky water; it will give you the creeps.

Try folding paper: http://www.flickr.com/photos/gj0kyz/
__________________
GJ0KYZ is offline   Reply With Quote
Old 11 August 2009, 02:33   #14
Member
 
Country: UK - England
Town: Cowes
Boat name: WightStuff
Make: Ribeye
Length: 6m +
Engine: Yamaha 150hp
MMSI: 235072807
Join Date: May 2009
Posts: 319
We've got a Ribeye S650, which according to the website has a draft at rest of 0.55m

I'm a little confused though, as to where the GPS/Sonar would measure the depth from.
__________________
BrAinZ is offline   Reply With Quote
Old 11 August 2009, 03:15   #15
Member
 
chewy's Avatar
 
Country: UK - England
Town: Up Norf
Make: Avon SR4,Tremlett 23
Length: 4m +
Engine: Yam 55, Volvo 200
Join Date: Apr 2007
Posts: 5,217
It'll be either through hull transducer or mounted on the transom.
You need to measure how far your leg goes into the water too.
__________________
chewy is offline   Reply With Quote
Old 11 August 2009, 04:39   #16
Member
 
Country: UK - England
Town: Dorset & Hants
Boat name: Streaker/Orange
Make: Avon/Ribcraft
Length: 4m +
Engine: 50Yam/25 Mariner
Join Date: Apr 2007
Posts: 5,551
I spend the first & last mile & a half of any trip in about 2-3 feet . Once you get used to it you stop worrying and you jusy go very slow. But as its all mud underneath its not to bad.

Following other boats in the channel can give very false reading as the mud is stirred up - but if a ' big' boat is in front you know they will hit bottom first !

Generally for me its only to shallow when the prop has to be out of the water to keep going!
__________________
PeterM is offline   Reply With Quote
Old 11 August 2009, 05:16   #17
Member
 
Country: UK - England
Town: Hull, East Yorkshire
Boat name: Hull Uni One
Make: Humber
Length: 6m +
Engine: OB, Petrol, 140HP
Join Date: Mar 2007
Posts: 121
We operate in the Humber. Shallow water is a fact of life!
Less then 1.5m sets off the alarm but you can get away with less than 1m under the keel if you proceed with extreme caution!
It's mostly mud and sand so not too much of a problem if you ground out at slow speed. The exception is the launch/recovery site which is a rock strewn mess.
__________________
Dry_Doc is offline   Reply With Quote
Old 11 August 2009, 05:44   #18
Member
 
Country: UK - England
Town: worcester
Length: no boat
Join Date: Aug 2008
Posts: 40
I like to check out the bottom on a low spring tide and take some photos and notes. As previous posters mentioned, drive slowly and with caution and enjoy the less accessible areas of our coastline.With the engine leg up a little the draft on most RIBS is fairly minimal. Watch out for falling tides on a spring as you may be stuck for quite some time. Most of the channels in the Solant are marked. Also check out your Reeds Almanac which will tell you how many hours either side of high tide you can enter a channel.
__________________
ben tye is offline   Reply With Quote
Old 11 August 2009, 09:19   #19
Member
 
Country: UK - England
Town: Scillies
Boat name: Freedom
Make: Searider
Length: 5m +
Engine: Yam 2st 90
Join Date: Jan 2007
Posts: 335
I regularly have to run in shallow water. I always consider anything more than 1 mtr as enough to full belt it. But I do know the waters I do that in well. The rest of the time, as others have said, proceed with caution and use your power trim and it shouldn't be too much of a prob. I'vwe only scraped the prop in the sand once n 2.5 years including regular beaching.

Ian
__________________
walruz is offline   Reply With Quote
Old 11 August 2009, 11:51   #20
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
The area I usually abalone dive has us launching in a tidal river, then running out to sea. Chioce of 2 launch spots: a concrete ramp in a small arm off the river, or into the river itself. Lots of skinny water. I always pull the stainless prop, and put on a (now beat to crap) aluminum wheel instead.

If I launch off the ramp, I have to get to the river itself, which is pretty much impossible at low tide, and a depth of maybe a couple of feet at high tide, over a bar of sand, pebbles, and mud. The bar itself tends to move with the flow of the tides. My transducer is just off the centerline of the hull, and has read as low as 1.2 feet or so without hitting anything (which isn't to say that I haven't hit stuff before...) With the motor trimmed way up, I sometimes have to get people out of the boat and walk/push/pull it over the bar.

The same goes for the mouth of the river (which you hit no matter where you launch), though there you can time the swell to help get over the really shallow part. High tide is generally no problem; 26' commercial fishing boats use the marina as a base (but time their arrival and departure for high tide, I think.)

The depth reading on my finder is, as far as I know, depth under the keel for the time being. I haven't set the offset yet (mostly laziness, but partly because I haven't decided which is best: display depth from the surface for diving, or depth under the skeg when trimmed in.)

Anyway, when it starts reading skinny water, trim the motor up, and go slow. And be ready to kill the motor if you hit anything unless you really dislike your current prop. And carry a spare, and the tools to swap it out.

jky
__________________

__________________
jyasaki is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 01:11.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.