How Crazy is it to get your boat LONGER ?

[TheThunderbird]

Atoll,
can we say that bows and stern are all alike, whatever the boat ?

Yes, indeed

[boatman61]

From what I can understand you are talking about storing toys in your transom..
Know at least one Jongert that does that.. they keep his Harley FLH and her Harley Custom along with the RIB in the transom of their boat.
Hydraulic drawbridge stern lowers and one rides out onto the jetty..
Mind.. it was a built to order 1 off 19m+ boat.

[TheThunderbird]

Great! I meant less extreme toys indeed (I have an MVAgusta 1000 ashore)

Ropes, fenders, scuba gear, a wet cupboard, fishing gear, hose pipes, a cumbersome Dinghy... And a rigid dink on deck, plus tiilting Solar panels, a garden for herbs now in the cockpit....endless possibilities...

Jongert sport full size stern sections, a nauta54 resembles a Swan of the same era and size (and drawing board)

Boatman, kudos, it is your second ever non-ironic contribution of yours after months... I feel pleased ��
Fair winds to all

PS I am mech. Eng. and have contacted a structural engineer, my old time friend teaching at Uni...we'll see

PS yes a trial bike like a Montesa could be nice to park on stern... Arg arg arghh!!

[unclemack]

My boat's already hideously ugly so that part wouldn't bother me too much.

Some trepidation about how it might behave in a decent following or quartering sea though.

[boatman61]

Originally Posted by TheThunderbird

Great! I meant less extreme toys indeed (I have an MVAgusta 1000 ashore)

Ropes, fenders, scuba gear, a wet cupboard, fishing gear, hose pipes, a cumbersome Dinghy... And a rigid dink on deck, plus tiilting Solar panels, a garden for herbs now in the cockpit....endless possibilities...

Jongert sport full size stern sections, a nauta54 resembles a Swan of the same era and size (and drawing board)

Boatman, kudos, it is your second ever non-ironic contribution of yours after months... I feel pleased ��
Fair winds to all

PS I am mech. Eng. and have contacted a structural engineer, my old time friend teaching at Uni...we'll see

PS yes a trial bike like a Montesa could be nice to park on stern... Arg arg arghh!!

You keep Count...??
I Feel Honoured....

[unclemack]

Originally Posted by boatman61

You keep Count...??
I Feel Honoured....

And maybe a little bit... stalked?
Heh heh

[boatman61]

Originally Posted by unclemack

And maybe a little bit... stalked?
Heh heh

Only if it was True...!!
Forums are like deliveries, work, some marriage's...
Only the shitty stuffs remembered...

[jimbunyard]

Is this your boat? If so, certainly you could do it, though if you followed the existing lines you'd end up with an almost canoe stern. Depending on your stern wave now, it may or may not affect seaworthiness in following seas. With the existing swept stern, you could probably add 6 feet of deck without adding much (if any) at all to where the 'addition' joins the lower point of the hull, just above the waterline, as long as you were willing to have an overhanging rather than a swept stern.

Strength wise, assuming you have a fiberglass hull, then the addition could be made with glass and any of the various structural foams in situ, or built off the boat and then attached with bolts and glass, and then faired in and painted. If it had no rigging stresses involved, the main force to worry about would be the effects of waves, but since there's no real reason to alter the existing hull at all (unless you for some reason want to penetrate the existing transom), there should be no problem making the hull addition just as strong as the original hull. I would be leery of attaching mooring cleats to the addition unless it was specifically engineered for them though.

To me the main question would be how the value of the boat changed. I'm guessing, depending on finishing and accoutrements, 25-40000 USD or maybe more to make the change, and in the end, even if done to the highest standards, will it wind up devaluing the boat?







And by the way I've actually done this, though on a much smaller scale, in conjunction with recoring and repowering a 24 foot fishing boat. We changed it into a 27.5 foot fishing/diving boat, the extra 3.5 feet is proportionally about the same as the change you propose, the difference is that on this boat the addition was load bearing, as we built in a slight negative camber to help lift the (slightly underpowered) boat on plane.

[Tingum]

If it is a metal boat it may be worth considering. If it is GRP forget it. Best suggestion was to purchase larger boat. My compliments on your vocabulary and grammar.

[Dave22q]

I generally try to be positive but that's not easy on this one. The idea that adding substantial weight and displacement while changing the lines of the boat will work out well is pretty far out. Navel architects are not generally considered a luxury that is optional. On the other hand, I seriously doubt that you could find one to participate in your experiment.
In short, the answer is that the idea is very crazy! It might work but I would certainly not bet on it.

[Sailor Doug]

Simple less expensive solution. A friend of mine had a deck level stern platform add to his 54' sail boat. I believe it was 6-8 long. Deck was teak strips with stainless supports. Big enough to carry dingy with out board. Hatch in new deck to boarding ladder. This would be a lighter less expensive solution.


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[captlloyd]

Go for it, hull extensions are not rockets science. Done frequently in boatyards. 6-8ft in GRP, not that much weight. A catamaran (more difficult yet) was done on ''YouTube'' by owner. I just hate uninformed negativity.

[sailorchic34]

Hull extensions are not rocket science.... on a power boat. Adding 8 feet to the stern of the 54 foot sailboat, changes the center of motion. The mast and fin keel would be too far forward then. It would, I think, effect sailing performance, perhaps with a tad too much weather helm.

Many manufactures do add feet to the center of the boat when they take an existing design and make it longer. But they also adjust the keel and mast dimensions so the boat stays balanced. Adding 8 to 10 feet to the stern of an existing sailboat, would adversely effect hull balance.

Can it be done. Sure. Should it be done, that is the question.

I think a naval architect or the manufacturer might be a better one to contact.

[Luther]

I grew up on my Dad's replica of a Rio de la Plata whale (pilot?) boat. When he built it he added a few inches between each frame which extended her from 32' to 37'.
She was beautiful, sailed well and was a great heavy weather boat (Cook Strait!) but had significant weather helm on the wind. A longer bowsprit improved that a lot.

[TheThunderbird]

I am in Holland, busy at contacting yards working Alu plates

I am encouraged to go further, and believe Alu is best for the purpose.

I keep you posted..

Thanks to all....��