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Old 13-01-2015, 10:46   #1
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Advice needed about skeg



Hello,

What i found out:

the skeg is built round a wooden insert. At a certain point glass mat is folded around the skeg. Then glass mats are layed up at the back side so the skeg. It has more thickness at the aft section to accommodate the thickness of the rudder.
When there is no paint or whatsoever water will easy flow between the layers.
Result: delaminations.
The wood inside the skeg is moist. And it stinks like acid.
That's why the skeg wouldn't dry out.
I hope we can replace the wood, and use stainless steel instead.
To do so, i will split up the whole skeg. (i hope i can)

Any more ideas?????
How to get rigidity again?
Can i get rid of the remaining moist in the split skeg? I mean: it's more than 3 cm. thick.

Taco.
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Old 13-01-2015, 11:04   #2
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Re: Advice needed about skeg

I found this site showing a skeg repair (powerboat, but still....)

Re-Building a Skeg - Morris Yachts

If you followed this approach, you would be cutting out large access "ports" on each side of the skeg, removing the wood, building up fibreglass on the inside to replace the wood, and adding extra fibreglass on the outside to add strength.

The other approach I can think of is to essentially cut the entire skeg vertically along the fore/aft centreline, and removing half of it. The other half stays where it is.

As the saying goes, you can measure your cloth many times, but you can only cut it once, so I'd do a lot of research before I started cutting!

Question : how about replacing the wood with just fibreglass? Stainless steel is going to corrode in that environment.
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Old 13-01-2015, 11:10   #3
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Re: Advice needed about skeg

Its the drill machine pushing the skeg everytime you drill a hole?? if you grab it at the bottom and push sideways you feel it loose from the hull? movement?
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Old 13-01-2015, 11:22   #4
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Re: Advice needed about skeg

MarkSF: thanks for the link. It's a good suggestion.
Slitting up as you said was my thought, but i am not sure about that.

Neilpride:No, the skeg is solid and rigid.

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Old 13-01-2015, 11:22   #5
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Re: Advice needed about skeg

Sad mess-sorry to see it.
In my experience,polyester resin will not stay on solid wood-too much moisture with attendant vapor pressure build-up,and then,leaks from outside.
It sticks fairly well to plywood,probably because ply has most of the moisture baked out of it,during manufacture.
Epoxy resin is much better at "sticking".
You need to replace the wood with some type of synthetic-? foam,whatever.
Or-was the wood just a "form",& not really reqd after initial construction?
Can you just leave it hollow,with a drain hole in bottom,to prevent freezing @ haulout,or any weird pressure build-up.
I don't know,but will follow this thread.I'm sure folks with more experience will contribute.
Cheers / Len
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Old 13-01-2015, 11:30   #6
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Re: Advice needed about skeg

Just viewed the Morris Yacht vid.
Can you cut an access panel out of one side,like they did?
This would preserve your skeg shape.
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Old 13-01-2015, 11:39   #7
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Re: Advice needed about skeg

Quote:
Originally Posted by Voyager269 View Post
Any more ideas?????
How to get rigidity again?
I doubt such a high aspect skeg ever added much more than a very marginal degree of "rigidity", to begin with...

You might consider cutting most of it off, and converting your rudder to a balanced spade, instead... No simple chore, would likely involving a complete rebuild of the rudder using a larger diameter shaft, etc...

My boat was originally built with a similar 'skeg', it was structurally worthless... I finally cut most of it off, and upgraded the rudder to a much stronger balanced spade, building the leading edge out to about 15% of the chord length forward of the shaft...

Turned out to be one of the best improvements to the boat I've ever made...


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Old 13-01-2015, 11:39   #8
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Re: Advice needed about skeg

Most likely the Ply form is formed during lay up the molds , then the top is glassed to keep the hull watertight there in case of skeg rupture, i hope so, could be a Split mold construction, 2 halves joined together , the ply form is put it in place, they close the halves and pour a mixture of resin in the skeg void to fill gaps and glass the top.. maybe just a idea..


I think your best bet is to PM Minaret in this fórum, it have plenty of experience with skegs and stuff like that, my sugestion coud be to open a window in the whole skeg and dig out all the bad plywood top, bottom, sides, fill it and reglass the whole skeg thicker to gain more strenght , after a good dry out of moisture ...


Just a idea, but Minaret sure come with the good one!!!
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Old 14-01-2015, 01:00   #9
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Re: Advice needed about skeg

Quote:
Originally Posted by deblen View Post
Just viewed the Morris Yacht vid.
Can you cut an access panel out of one side,like they did?
This would preserve your skeg shape.
I am not sure yet, will find out. But it shall be a difficult job.



Jon: Converting our rudder to a balanced spade is possible, but that's much more work then repair the situation we now have.

Neil: If Minaret is not turning up right here, i will contact him. Thanks.
Interesting thoughts you have about the building of the sailboat. You could be right about that. Because i found some poured resin.
Taco.
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