Hull Stress

Fire99

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Hi All...
Could you please be of some assistance.
I currently own a Norman 18ft Motor Cruiser with a 40 hp Yamaha Outboard and 4.5 hp auxillary.. I use the boat on the River Blackwater in Essex. It gets quite choppy on the river as you get closer to the Estuary and I was wondering what kind of abuse the Hull of my boat can take since she gets buffeted about quite a bit and items of trim are often falling off.. Also what is the best procedure for navigating the waters if they do get a bit choppy? Should you keep the speed high and attempt to plane over the top (which gets very bumpy) or should i slow down and attempt to ride over the waves?

Any information would be greatly appreciated since I am new to tidal / coastal waters..
Many thanks

Nick
 

kimhollamby

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You can overstress any boat if you try hard enough. Your Norman was built in an era when they tended to be more generous with GRP lay-up and less worried about weight and raw material cost so you are probably safe to push on but if in doubt, take it slower.

Also watch out in your case for forward windows, if you have any in the saloon, or a weak foredeck hatch. Should you get it wrong and take a wave over the front it can become very tricky if you take out the glazing.

Remember to use the throttle to assist the bow; more throttle tends to lift the bow and less drops it, so one hand for the wheel and one for the throttle is always a good idea when waves start to bite.

The biggest stress to the hull comes in waves directly ahead, so if there is enough room to do so you can always take a zig-zag course (a bit like a yacht tacking) in order to make the conditions more comfortable for you and the boat.
 

miket

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I know the area that you are using, and whilst your boat is fine for the areas inland from the mouth of the estuary in fine conditions I would be wary of going too far downriver in inclement weather.

My memory of the Norman range is that they were primarily river and canal boats. Any boat is OK on fine days, but be careful on rougher days.
 

Fire99

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Thanks for the Info.. Prior to me purchasing the little Norman, it was being used for Crab Fishing off the South Coast of Cornwall...But i wasnt sure if that just meant that the guys were mad!!

Thanks again..
 

Fire99

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Thanks for the reply....
I was concerned that the inside of the boat gets a real battering when it hits some waves and I wasnt sure wether to try to plane over the top or to back off..
Your info explains that..
I think the other point is that the larger normans always seem to be used on canals and rivers and this little one used to be used as a crab fishing boat off the South Coast of Cornwall..
Thanks again for the reply
 

Fire99

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Thanks for replying...
I was concerned that the inner part of the boat rattles about alot and a few fittings and fixtures have come adrift. Also that the Norman is very small and i wasnt sure of its intended purpose.. Even though it was used for Crab Fishing off the South Coast of Cornwall before I purchased it.
I know the larger normans appear mostly on Canals and small rivers but they always seem to be narrow beam boats.
My little one seems better proportioned.. I could be wrong though..
Thanks for the info.
 

byron

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Things do fall off. I recall when the Princess 55 first came out, the owner brought it straight to St Kats. he was a little concerned about locking through so I was asked to bring it in for him. I found the boat a joy to handle at low speeds and enthused about it, he then took me below to show me, doors were hanging off, bits had come unscrewed and stuff had pulled away and there were 33 major faults (but that is another story) When questioning him I elicited the fact that he had pushed the boat regardless of sea conditions all the way from Plymouth which in my view is asking for trouble. This only goes to show that even bigger boats have to take into account sea states. For my part I wouldn't want to take anything down the Thames Estuary in a N.E.6 wind over tide. Once down at sea reach it will hammer anything to extreme.


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Fire99

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This has been my first year of owning a boat and you always get a bit concerned when the floor feels like its flexing and your shiny barometer has just launched itself out of the door. So just to clarify a point on a little planing boat like this, when it gets choppy do you back off and slowly make your way through the rougher water or do you continue to attempt to plane over the top. The reason i say is that one person once said that a planing boat was only safe while it was on the plane.. I was a bit concerned over the weekend when my boat was acting more like a jet ski....
 

longjohnsilver

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Having owned a similar sized boat in the past you definitely don't want to plane in rough conditions, not only could it damage the boat but it could easily cause injury to you, which could be very unpleasant in rough conditions.
 
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I used to have a little Hardy Pilot 20' in this area. It used to get thrown around in a 3 to 4, however, it was fun but I wouldn't go out in anything more than this. It is a wide eastuary with the Colne and Blackwater converging giving strange currents, and can be particularly rough during wind against tide.
I've gone up to a 26' Sunfury and the ride is much more comfortable. However, there are plenty of places to explore.
 

Col

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If you have trim tabs/trimmable out drives,put the tabs/drives right down,this will lower the nose and help stop it taking of like a motorcross bike.
It will push through the waves more(and you will get wet!)but it is kinder to the boat.any planing boat will work at displacement speed, In fact a couple of years ago, I came back from the Channel isle's at 10knts because the sea was still stirred up from week long gales,( I normally cruise at 30+)
hope this puts your mind at ease.
 
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