Balancing the BOAT???????
#32
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#34
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Excellent topic,in the spring I also plan on finding the balance point on my boat front to rear. I am personally overweight and when I run my 4700 lb boat with no passengers in the rear seat it tends to bow steer violently at high speeds. It never seemed top do this before but I almost always have ran with rear seat passengers. lighter exhaust and cylinder heads have amplified my problem,I'm thinking Ineed to add about 100 lbs at very rear of boat. Example 1-blew a fuel pump fuse at almost 95 mph with rear seat passengers,transom settled down first and boat glided gently to a stop (had a hard time getting passengers to ride in boat again though).
Example 2-opposite-was running mid 90's with 1 passenger in front seat,started backing out of throttle and bowed dropped quickly causing boat to bow steer violently UNTIL azz end settled in.
My plan is to place weight equivilant to mine in driver seat area and same with pass seat area then sling boat to find cg fron to rear. Then I plan on mathematically calculating how much weight I need at rear of boat to be equivilant to about 400 lbs of rear seat passengers that seems to be what balances out my boat properly.
I/E-If 400 lbs 2 feet behind the fore/aft cg makes boat properly balanced,instead of adding 400 lbs there I would add 50 or 100 lbs further back to get the same effect without weighing boat down so much it hurts the ability to air out and reach top speed. I'm thinking a 80 lb water inflated ballast bag with a fill pump and a solenoid drain placed in the molded hollow swim platform my boat has. Great thread,keep the ideas coming,Smitty
Example 2-opposite-was running mid 90's with 1 passenger in front seat,started backing out of throttle and bowed dropped quickly causing boat to bow steer violently UNTIL azz end settled in.
My plan is to place weight equivilant to mine in driver seat area and same with pass seat area then sling boat to find cg fron to rear. Then I plan on mathematically calculating how much weight I need at rear of boat to be equivilant to about 400 lbs of rear seat passengers that seems to be what balances out my boat properly.
I/E-If 400 lbs 2 feet behind the fore/aft cg makes boat properly balanced,instead of adding 400 lbs there I would add 50 or 100 lbs further back to get the same effect without weighing boat down so much it hurts the ability to air out and reach top speed. I'm thinking a 80 lb water inflated ballast bag with a fill pump and a solenoid drain placed in the molded hollow swim platform my boat has. Great thread,keep the ideas coming,Smitty
#35
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Smitty,Perhaps there are other options,such as mufflers,hatch pads,etc....we are tinkering with a little different muffler design, though it is premature to go into detail.
Ben,Is it possible your boat could benefit from a bit more aft CG?
Thanks for the compliment....However,everyone would surely appreciate pictures of your ballast tank and plumbing.
Ben,Is it possible your boat could benefit from a bit more aft CG?
Thanks for the compliment....However,everyone would surely appreciate pictures of your ballast tank and plumbing.
#37
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Has anyone tried to hang a counter weight off the back of the transom...over the drive or something like that. It would stand to reason that the further back the weight is located the less weight that you would have to add to your boat. Like a lever. Just asking? I know that I have heard of people adding lead in the swim platform when they have those tubular add on swim platforms.
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I think the most eficient way to balast is ,,,first use what u have,,,,,ancor ,batterie's,rops,cooler,trimmpumps,and all other stuff. If you can't acomplish the CG right with that, then either 2 fueltanks and pump fuel back or forth/side to side ,,,,now your not add. adintional weight to the boat ,,,at last if still not working u need a removable balast like a watertank where u can pump water in and out when and where needet.
I hate using dead weight like lead or sandbags because it will never be right when u need it since watercondition change to often .
Thats just me ,,,but a perfect CG is not just make the boat fly level its also about NOT beating the $hit out of you,,,,therefor it actually should be right behind the backrest of the seat since the force should be where u sit /stand or u beat your bones up real quick.
And like sayd earlier ,,the best way to check is with a floorjack and block of would.
Lift it up and if u can move the boat with almost no force by hand thats where your CG is when jack is placed under it.
If not there ,,,now move weights in the boat to get it there.
Remember place floorjack under backpart of seat !!!
I hate using dead weight like lead or sandbags because it will never be right when u need it since watercondition change to often .
Thats just me ,,,but a perfect CG is not just make the boat fly level its also about NOT beating the $hit out of you,,,,therefor it actually should be right behind the backrest of the seat since the force should be where u sit /stand or u beat your bones up real quick.
And like sayd earlier ,,the best way to check is with a floorjack and block of would.
Lift it up and if u can move the boat with almost no force by hand thats where your CG is when jack is placed under it.
If not there ,,,now move weights in the boat to get it there.
Remember place floorjack under backpart of seat !!!
Last edited by DareDevil; 01-31-2009 at 09:21 AM.
#39
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Has anyone tried to hang a counter weight off the back of the transom...over the drive or something like that. It would stand to reason that the further back the weight is located the less weight that you would have to add to your boat. Like a lever. Just asking? I know that I have heard of people adding lead in the swim platform when they have those tubular add on swim platforms.
On a side note I took my boat to Mackinaw island 2 years ago out on the big water and we took 2 people with us and all kinds of luggage,lawn chairs,full tank of gas,a small grill,3 coolers etc. the boat was really loaded down to where it felt sorta sluggish and heavy,I didn't take it over 75 mph for fear of blowing a drive 15 miles from port out on lake Huron but we ran into 3-4 footers and the boat felt the best it ever did,it crushed thru the waves like a real offshore boat instead of bouncing in every direction like it usually does,I was thinking that must be what it feels like to drive these boats that people talk about being built like tanks and heavy like a 28 foot cig or something,Smitty
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