Donzi Magnum TUNNEL HULL

NYGiants

NYGiants

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I picked up this boat today, its a 1976 Donzi Magnum tunnel hull. The previous owner ripped out most of the rotten stuff, leaving me with the task of putting it back together. Im not entirely sure where to start or how to start, so all of your input will be welcome.
 

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GA_Boater

GA_Boater

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I wouldn't where to start either, NYG. She's a project for sure.

Is that the bare transom wood showing on the pic from the back? Good luck on the resto.
 
NYGiants

NYGiants

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GA_Boater said:
I wouldn't where to start either, NYG. She's a project for sure.

Is that the bare transom wood showing on the pic from the back? Good luck on the resto.
Click to expand...

Yup, thats the bare wood. It's basically a gutted hull at the moment.
 
Woodonglass

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Do you have the fiberglass piece that he cut out of the rear of the boat???:eek: Having to fabricate a new one will be a bit of a chore but can be done. Tying it back into the rest of the fiberglass structure will also be a bit of a challenge since he didn't leave any lip. It's gunna be necessary for you to gain access to the inside of the hull to make structural attachments to the inner skin with the new outer skin if you want the hull to be structurally sound.;)
 
sphelps

sphelps

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Yeh he sure didn't do you any favors cutting the back out ... Can the cap be removed ?
 
GA_Boater

GA_Boater

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If the pic shows - This ain't gonna be your normal job. I think the cap has to come off to fit the wood from the inside and put the cap back on and re-make the transom skin. I hope the price was right - That you were paid to haul the thing away.

Sorry NYG, but your have a chore to get this one right.

fetch
 
Yacht Dr.

Yacht Dr.

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Meh..not really a big deal.

Get the wood out..put some new stuff in there then glass the transom. The hardest part will be wrapping the edge all the way around to the sides/bottom..but still not all that bad if you take your time glassin.

Depending on how hard it is to get to some of these things..going at it from the outside might be the fastest and easiest way sometimes. Hell Id rather be sittin down in my rolley chair than getting my knees blown out in the bilge ;).

Get that wood out and see whatcha got. At this point there is no reason to start cuttin from the inside..you probably dont want to do that anyways now.

Good luck.
 
Woodonglass

Woodonglass

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Yacht Dr. said:
Meh..not really a big deal.

Get the wood out..put some new stuff in there then glass the transom. The hardest part will be wrapping the edge all the way around to the sides/bottom..but still not all that bad if you take your time glassin.

Depending on how hard it is to get to some of these things..going at it from the outside might be the fastest and easiest way sometimes. Hell Id rather be sittin down in my rolley chair than getting my knees blown out in the bilge ;).

Get that wood out and see whatcha got. At this point there is no reason to start cuttin from the inside..you probably dont want to do that anyways now.

Good luck.
Click to expand...

This IS the challenge and with this type of boat and depending on the HP motor that you plan to hang on her I'd be dubious as to the overall integrity of the layup. YD does this for a living and he knows his stuff but the way this has been cut out it will be difficult to be made whole again. IF the inner skin IS thisk and well attached to the hull then it might be doable. A lot more Pix will help us to help you
 
NYGiants

NYGiants

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I got the boat for free with the trailer, and it has all the paperwork (thank god) Worst case scenario that trailer is worth about 300-350. I think it's an awesome boat, and I read over on donzi forums that they only made 30 originals (and another manufacturer bought the molds and reproduced them, but lower quality). I read that people put around 150hp on these, the previous owner had an 80 on it and hit 45mph. I have a large album at this link, alot of high quality pictures http://imgur.com/a/uWS7w#0


 
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Woodonglass

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It appears that someone made an attempt to do some glassing already on the transom. There appears to be some glass wrappings around the edges already. Trying to do this and make it look good and be structurally sound, IMHO, will be challenging unless you have good glassing skills.;)
 
Woodonglass

Woodonglass

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If the top half separates from the bottom half then...Yup that's the best way, IMHO to do it. At the very least cut the splash well and the top section about 2 ft in front of the transom to allow access to the rear of the boat and rebuild the back and then glass the back top portion back in. To me, that would allow you to make a much stronger and more reliable structural boat.
 
NYGiants

NYGiants

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Woodonglass said:
If the top half separates from the bottom half then...Yup that's the best way, IMHO to do it. At the very least cut the splash well and the top section about 2 ft in front of the transom to allow access to the rear of the boat and rebuild the back and then glass the back top portion back in. To me, that would allow you to make a much stronger and more reliable structural boat.
Click to expand...
It looks like someone started to seperate the cap from the bottom shell, or at the very least theres cracks the whole way around

Why would i need to remove the splash well? I should be able to squeeze in the plywood without removing it or the shell.
 
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chconger

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sphelps said:
Is it a balsa cored hull ?
Click to expand...

I think its at least a balsa cored deck. (and by deck I mean where it says "Magnum"...not the "floor" as folks say)

What WOG saw as someone's previous attempts at repair " glass wrappings around the edges " ... I am betting are in fact the edge of a cored deck.

That would make sense in a tunnel hull as you need that deck to be rigid enough to stand on, but still light.

Would be worth sampling from under side.


Neat boat!

Chris
 
NYGiants

NYGiants

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chconger said:
I think its at least a balsa cored deck. (and by deck I mean where it says "Magnum"...not the "floor" as folks say)

What WOG saw as someone's previous attempts at repair " glass wrappings around the edges " ... I am betting are in fact the edge of a cored deck.

That would make sense in a tunnel hull as you need that deck to be rigid enough to stand on, but still light.

Would be worth sampling from under side.


Neat boat!

Chris
Click to expand...
Do i need to add stringers or just a transom?
 
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