How to prevent my boat from rock&roll?

peterjaw

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Good day, captains,
My boat is 8 x 3 meter, about 4 tons (weight).

I realise that when I rest for fishing the swell causes my boat to rock&roll like the
metronome on the piano. But all the other smaller boats around me just move up and
down with the swell. The swell is just 70 ~ 100 cm. and comes for every 5 ~ 6 seconds.

No matter how I adjust my boat's facing, it ends up with "side impact".

Is there any method to improve or avoid? ( I am not affordable to install a stablizer.)

Is the period of the swell related?
 
Peter why not get an electric trolling motor, like on the front of this boat

You could then face which ever way is more comfortable
 
Ah, bucket over the side it is then, sometimes I've found an anchor in the bucket helps a lot, if there's a kedge going spare.

Or have something like an old Mirror rig and stuff it up as a riding sail at the back...:)
 
If there's any wind and you are drifting A bucket tied to the bow may act like a drogue and stop you sitting beam on to the waves
 
Additional ballast in the bilges will make a big difference but if you want to plane this will adversely affect the speed.. If displacement then just keep adding ballast until the roll is acceptable. This from experience!!!
 
It's going to take a huge amount of ballast if the boat doesn't have a keel or the inertial damping of a rig; my boat is wide beam and has a deep keel with 950lbs ballast bulb on the end, 40% ballast ratio, she's very stiff under sail; but when the mast is down she's surprisingly susceptible to roll, something reported by people on big blue water boats when dismasted.
 
There are two good solutions. A flopper stopper type of device and or an anchor arrangement to hold the bow into the swell. Move the bow angle with either a kedge or a second line from the rode to the stern.
 
If you are serious and ready to spend some money, the ultimate solution is a gyroscopic stabiliser. You would be looking at quite a few grand though.
 
Additional ballast in the bilges will make a big difference but if you want to plane this will adversely affect the speed.. If displacement then just keep adding ballast until the roll is acceptable. This from experience!!!

I was told that placing the ballast centrally can actually make the roll much worse- you are turning your boat into a pendulum.
Instead, it should be placed at either side of the bilge, to increase the moment of inertia (I think that's the right term).
 
Thank you very much for all your suggestions, guys.

It seems that the basic concept is to hang something weight enough on one side to reduce the influence.

I don't have a boom and is it safe to use the center cleat? The deeper the better or I need to adjust accordingly?
 
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Appreciate for your bucket suggestion.
My boat is a motorboat with outboard.

Yes I have already been told this, so I downgraded to a bucket over the side, ideally with a spare kedge anchor or other weight in it; good luck, I hope either this and / or anchoring ( if depth suits ) and having a line from the stern to the anchor warp so as to adjust the angle she lies at, as Zing mentioned, at least helps a bit.

If yo mean a foredeck mooring cleat it's a bit far forward, midships would be best but that may not be available to you ?
 
Thank you very much, Bauba. This looks like a good idea.
What is the benefit with this trolling motor over my outboard?
If you spend hours fishing you don’t want to leave your big outboard running all the time. With electric it switches on instantly, also you can have foot controls so you can use it while still fishing (you don’t have to put your fishing rod down).
This is a very common thing for a fishing boat to have, they are not too expensive also you can put it on the front, back or corner of the boat, which ever is the most effective. The boat will move easier if the big outboard is raised up out of the water.
That is also something that you can test, when fishing see if the boat drifts differently when the outboard is in or out of the water. But it’s been my experience that all boats end up with the waves at the side, which is always the most uncomfortable.
 
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