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Old 26 December 2013, 12:33   #1
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ballast in the bow

A point for discussion

Is it possible to have too much weight in the bow of a rib when facing a head sea? If so how would you know?

I am aware of the problems of a heavy bow and a following sea

TSM
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Old 26 December 2013, 12:36   #2
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waves breaking over the bow would be a sign.
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Old 26 December 2013, 13:29   #3
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Or going down nose first like a sub lol.
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Old 26 December 2013, 19:29   #4
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Quote:
Originally Posted by two stroke mick View Post
A point for discussion

Is it possible to have too much weight in the bow of a rib when facing a head sea? If so how would you know?

I am aware of the problems of a heavy bow and a following sea

TSM
Hi Mick...happy christmas!
a bows heavy boat won’t steer well, take longer than it should to get onto the plane; and will use a ton of fuel doing so.
Think you have to trial and error a little to see whats right for your Valiant, am sure there are some other Valiant owners with direct experience who could help you on here.
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Old 27 December 2013, 02:29   #5
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Hi Must rib

I was just thinkingf aloud if it waspossible to have too heavy a bow on a rib in a head sea

thanks for your input

tsm
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Old 30 December 2013, 19:20   #6
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Nearly lost a boat in breaking head sea's, despite full trim tab. More weight would have saved the day. As for being slower to plane, thats not what I have experienced, the bow being forced down overcomes the bow wave easier, therefore it planes. A bow that rises planes worse, hence why you trim down before tyring to plane.

Current boat had a 500-600kg bow ballast tank, I have down sized it to 100kg, but weight up front can be very handy, especially if its moveable or temporary.

Tabs will solve 85% of those problems though
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Old 31 December 2013, 07:47   #7
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Surely trim tabs only work when moving...? The faster you go the more they work?

So bow tanks etc solve that problem?
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Old 31 December 2013, 08:44   #8
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Surely trim tabs only work when moving...? The faster you go the more they work?

So bow tanks etc solve that problem?
I put two bags of B&Q's sand ballast in the anchor locker of my 9m Hunton, which had no tabs; it worked magnificently. The benefit is you can play with the weight to get it about right and simples if you want less in a hurry!

Sent from my iPatch using Rib.net
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Old 01 January 2014, 18:03   #9
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Surely trim tabs only work when moving...? The faster you go the more they work?

So bow tanks etc solve that problem?
Trim tabs start working the moment you move. But not all ribs are stable at displacement speed. in my case i was in breaking seas a few meters high, every few seconds. tabs help keep the nose down, therefore you plane quicker, if however the waves are so big, you cant get enough speed to make the tabs work, or the lifting effect of the waves on the front lift the bow, negating ability to plane. ur......... well buggered. My only solution would have been weight up front to reduce how much rocking horse the boat could do.

Sand ballast is a brillaint solution, I used to keep one 20kg bag in the front of my 6m american hard boat which was rubbish in a head sea, beam sea and following sea for that matter. One day when it was too rough in a following sea i just ditched it overboard. That small amount of weight changed whole attitue of the little boat. Just like gentleman racers hunton. Awsome boat, with awsome hull, yet 6 worth of sand has obviously made his ride better...

SO to answer TSM question, weight in bow can only be too much if the weight makes the nose go lower than the stern, and then the boat could pitchpole. Otherwise I swear by it in my little experience.
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