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Old 04-09-2012, 01:03 PM   #1
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Has anyone added Ballast to a 34 Mainship?

Just as the title asks. I have a Manship 34 III with the 200 Perkins. Anyone with one of these (Any of the early 34s) ever add ballast? I've been reading about how adding weigh in the keel can sometimes make the snap roll worse, but I really think it would help keep my boat more stable by reducing the initial roll amount. My boat feels "light" when going at really low speeds. I think some added mass right in the bow would help to reduce some of the pitching, but I'd really like to address the roll's severity and speed. I would love a set of paravanes but have not seen any on a 34 MS so I was considering adding weight. What do others use and where do you source it? Concrete was a popular material on the commercial shrimp boats I grew up with.
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Old 04-09-2012, 04:37 PM   #2
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You could ballast the Gunn'ls or the Chine's to reduce the "snap" in the roll but I wouldn't advise it. If you run at slow speeds stabilizers would work well. With the narrow bow of your boat adding weight fed would be bad and adding weight aft would increase transom drag. Stabilizing sails may be considered too. Not large and mounted well aft. I'll ask my local Mainship 34 owner. He was a fisherman and knows much about roll.
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Old 04-10-2012, 05:20 AM   #3
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If the boat has a mostly round bottom , the roll will start sooner and go further , but not sicken most folks.

Flat bottom or chines will help stepping aboard at the dock, but the snap roll can upset many guests.

LOADS of weight might slow the roll , but you would be down many inches from the DWL , and even displacement speeds would suffer.

Chines are usually on a "semi plaining" boat , and the stability does increase with speed.
Cheaper to run at 8-16 gph than change boats or add electronic/hydraulic stabilization.

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Old 04-10-2012, 09:08 PM   #4
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Call the manufacturer if they are still in business. They can tell you how much deeper your boat would sit in the water for each 1,000 lbs. You might not like the answer,
Another choice would be add more water tanks. Only problem is if the added ballast is not in the center of the boat, say for instance 1 tank on each side, this will make the rocking last longer. Most boats are designed to most efficient and most comfortable at their designed cruising speed. The most efficient is based on anything above put-put speed or above the theoretical hull speed.
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Old 04-10-2012, 10:20 PM   #5
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I just filled my water tanks in the stern (100 gal). Raised the bow 1.25".
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Old 04-11-2012, 05:52 AM   #6
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I just filled my water tanks in the stern (100 gal). Raised the bow 1.25".
Now if you just had a bow tank.....................
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Old 04-11-2012, 06:02 AM   #7
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For someone that will look in a book, there is a difference between "inch of immersion " and "inch of trim".

The first is how much weight to sink the entire boat an inch,
the latter is just to raise r lower one end.

On a 34 ft boat about 1000lbs would be my guess (without the numbers) for an inch of of immersion.

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Old 04-11-2012, 08:28 AM   #8
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sounds like if we keep her long enough that I may just have to engineer an A-frame and go with booms and paravanes. These would be my first choice if it weren't for the fact that most of the boating we do is on/near the Caloosahatchie river and the amount of traffic near the mouth of it where we live won't let me run with the booms out safely and they are one of the main reasons I'm looking for more stability. I need a 40-50K pound boat instead of the #16K we have now! It's only money, right. Hopefully this summer will be better once the majority of our boaters go away.
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Old 04-11-2012, 09:02 AM   #9
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sounds like if we keep her long enough that I may just have to engineer an A-frame and go with booms and paravanes. These would be my first choice if it weren't for the fact that most of the boating we do is on/near the Caloosahatchie river and the amount of traffic near the mouth of it where we live won't let me run with the booms out safely and they are one of the main reasons I'm looking for more stability. I need a 40-50K pound boat instead of the #16K we have now! It's only money, right. Hopefully this summer will be better once the majority of our boaters go away.
I think this is a better strategy....small boats are just that...only huge engineering (mostly impractical) feats are necessary to change that....unless you go with the throw money at it theory (a gyro system worth more than the boat).

As the doctor says...."does it hurt when you do that?"..."well stop doing that!"....

If your boat bounces, pitches, rolls too much (and your boat actually has a good reputation for all around attributes for coastal cruising)...you need to find out ways to enjoy your cruise (evaluate weather, traffic, loading...etc...etc)

Remember...if you go paravanes...if you can't run with the arms down..the REALLY hurt your rolling...especially if the rig is big compared to your boat (which I think it would be in your case).
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Old 04-11-2012, 09:27 PM   #10
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I know a guy who added lead ingots to his entire keel. He thought it helped,others who took trips on his boat said it did not help. I never took aride so i can,t say ond way or the other.
Having owned a mainship 1 for 14 years, i never felt the needfor additional weight.
I thought it handeled fine.
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Old 04-11-2012, 09:42 PM   #11
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You might want to check with Cherubini Yachts in Riverside NJ. John Cherubini designed the original Mainship 34. Dave Cherubini runs the operation now. they build classic runabouts and ocean going sailboats. Dave may still have the original designs, or his uncle John may still be around. In any case, Dave is a pretty good marine engineer and he might be able to give you some advise. Their phone is 856-764-5319. His yard is attached to our marina
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Old 04-12-2012, 08:45 AM   #12
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Originally Posted by twiisted71 View Post
Just as the title asks. I have a Manship 34 III with the 200 Perkins. Anyone with one of these (Any of the early 34s) ever add ballast? I've been reading about how adding weigh in the keel can sometimes make the snap roll worse, but I really think it would help keep my boat more stable by reducing the initial roll amount. My boat feels "light" when going at really low speeds. I think some added mass right in the bow would help to reduce some of the pitching, but I'd really like to address the roll's severity and speed. I would love a set of paravanes but have not seen any on a 34 MS so I was considering adding weight. What do others use and where do you source it? Concrete was a popular material on the commercial shrimp boats I grew up with.

I have a mainship 400 as you see in the picture the fact that it is semi-displacement sort of calls the shots the boat is very buoyant and bounce around.
dont think that you can convert semi displacement to full displacement those boats bounce around also .
Here is my suggestion could you add concrete building blocks to start with rather that concrete at least you can move the blocks around for trim. t you could weigh one block to do the math. if it were me i would only use lead.
I think that you may need to talk to other 34 owners first .

good luck .

for my money i would not mess with the boat.
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Old 04-12-2012, 09:02 AM   #13
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Ditto that. A 34 ft boat of 8-9 ton is going to be more bouncy than a 40 - 50 footer, but that does not mean it's not seaworthy, just that you try and avoid the type of situations where it is not going to be comfortable - or keep those experiences to a minimum, at least. A larger boat cost a lot more, takes more of everything to fuel and maintain, and often more crew, and can get into less cosy places. It's all a horses for course game really. I lust after a Fleming 55, but when I ask myself, seriously, how much use would I get out of it, worthy of that boat, and that my CHB 34 couldn't cope with just as well...the answer is...not much..not $2 million worth for sure.
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Old 04-12-2012, 11:36 AM   #14
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Out of curiosity, where is a good source for bulk lead?
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Old 04-12-2012, 11:41 AM   #15
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"but that does not mean it's not seaworthy,"

An interesting concept is define "Seaworthy".

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Old 04-12-2012, 11:52 AM   #16
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"but that does not mean it's not seaworthy,"

An interesting concept is define "Seaworthy".

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Yep kinda like beauty being in the eyes of the beholder.

To me if means that a vessel is mechanically and structurally solid enuff to make me feel comfortable in its ability in the conditions I'm going to take it out in. I will take my boats out in conditions where I am the only boat I'll see untied that day! I'm not a thrill-seeker, I've just grown up on many sizes of boats and we couldn't always pick and choose our days. I generally find and remedy (as well as can be) my boat's weaknesses soon after acquiring them. My main complaint with my boat is how it responds to wakes when being overtaken.
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Old 04-12-2012, 03:59 PM   #17
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before you go adding weight check the righting movement of the boat as it is.
This is mostly for sail boats with all that weight overhead ,Mast, boom ,sails.
It all depends on the center of gravity. and how quickly she snaps back after a bit of a roll.
This can be figgured by using a little trigonomitry and proper measurements.
I would not add weight without calculating everything on paper first.
You can get the numbers with a plum bob a yard stick and a couple of heavy friends
Have your friends of known weight stand amidships. suspend a plumbob from the overhead center of the cabin with a yard stick laying athwartships. Next have them move to the rail enough to heel the boat. mark the angle on the yard stick to give an angle of heel. I will need to get out my trig books to continue but it should tell you what the added weight will do for the righting movement of the boat. and how quickly she will snap back.

If you need it I will break out the books and give you step by step instructions as I did it with my boat.

Buy the way weight in the keel wouldn't help my boat. I stuck with the paravanes.


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Old 04-13-2012, 06:22 AM   #18
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Yep kinda like beauty being in the eyes of the beholder.
My main complaint with my boat is how it responds to wakes when being overtaken.
Having had a Maritimo 65 blast past just on Easter Monday @ about 20kn, on the (semi)plane, without slowing, and certainly closer that they are supposed to be in such a situation, I can tell you, no matter how much lead you put in your keel, it would not deal with it any better - quite possibly worse. It would respond slower to the helm, and the only recourse in that situation is to bear away - fast - so you take their wake on your stern quarter if they are coming up from behind - the worst scenario, and best handled by plenty of warning. Or, turning diagonally into the wake wave if it is coming towards you, the latter being a lot easier..
Just forget the extra ballast is my honest suggestion,and maybe fit a rear view mirror somewhere. I have found mine quite helpful in that situation, a car towing extension mirror seen here mounted on that shiney pole the upper steering etc runs thru - good to make some use of the brute...well...not seen here actually, because we seem to have lost the facility to attach images from iPhoto etc as it only appears to offer a URL option for an image outside the computer.
Ok, guys what am I missing here...this is the first time I've tried to add an image on the new site.....surely there is a way to tap into one's own collection..? Marin..?
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Old 04-13-2012, 06:35 AM   #19
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"It all depends on the center of gravity. and how quickly she snaps back after a bit of a roll.
This can be figgured by using a little trigonomitry and proper measurements."

The usual way to measure roll is to time the roll period.

Jump on the edge of the boat and then step off to make her rock in the slip.

You may have to loosen some dock lines to give the boat freedom to roll.

One roll is figgured as the time to complete a full cycle . from up thru down to up again.

Time the roll with a stop watch thru 10 full rolls, and divide by 10.

That will be the "roll period". Longer is more comfortable.

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Old 11-30-2012, 06:34 AM   #20
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My GB42 has a radar ss "bridge" in the fly that is heavy.
I tryed a PVC flexible water tank, placed in the bilge, thus below engines weight, up to 200 liters of water. It worked well, no loss of speed. If you do not like it, you always can remove it, or even use it as reserve of sweet water. cost is about $100
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