BlackPig
N/A
http://wavetrain.net/news-a-views/7...ilure-what-really-happened-to-polina-star-iii
glad I got a long keel as part of my hull.
glad I got a long keel as part of my hull.
ANOTHER MAJOR KEEL FAILURE: What Really Happened to Polina Star III?
- Thread starter BlackPig
- Start date
sailorman
Well-Known Member
lw395
Well-Known Member
Doesn't matter if your keel is long or short, if the laminate is weak due to shoddy layup (as that article seems to be implying) it might still fall off.
The deep-stub construction actually has a lot in common with 'old fashioned' long keel boats with external ballast.
15mm thick grp strikes me as quite thin for a keel stub on an 85ft (/whatever) megayot.
It's not like Oyster are trying to build 1000 of these cheaper than Bavaria is it?
The deep-stub construction actually has a lot in common with 'old fashioned' long keel boats with external ballast.
15mm thick grp strikes me as quite thin for a keel stub on an 85ft (/whatever) megayot.
It's not like Oyster are trying to build 1000 of these cheaper than Bavaria is it?
lw395
Well-Known Member
This is what happens when people are too clever to write thread titles which tell everyone exactly what the thread is about.....
adwuk
Well-Known Member
I think it just shows how some threads evolve over time, and especially highlights those OPs who are mature enough to accept this evolution
BlackPig
N/A
Not mine, it is the hull not stuck on.
lw395
Well-Known Member
The bit that broke off this boat seems to have been part of the hull too!
prv
Well-Known Member
+1
It's perfectly clear in the pictures that the iron (or lead?) keel is still securely bolted to the GRP.
The GRP itself broke, about 18" above the joint to the metal. An encapsulated keel built so weakly would have failed in exactly the same way.
Pete
nigelmercier
RIP
- Joined
- 20 Jun 2007
- Messages
- 16,234
- Location
- Live in Kent, boat in Canary Islands
Oh, so that's what the other thread is about, I've ignored it for the reason you state.
sailorman
Well-Known Member
You are allowed to have a peek :encouragement:
prv
Well-Known Member
lw395
Well-Known Member
I wonder about the earlier repairs reported, which seem to include tightening the keelbolts.
I speculate that the hull and keel didn't fit together properly and tightening the bolts over-stressed the GRP structure trying to force it to fit the keel???
I speculate that the hull and keel didn't fit together properly and tightening the bolts over-stressed the GRP structure trying to force it to fit the keel???
sailorman
Well-Known Member
as stated elsewhere those bolts are well inboard from the keel outer edge
Mandarin331
Well-Known Member
+1. That was the thicknes of the hull of our last boats grp by the keel, she's 30`
Seajet
...
Your last boat was underbuilt too then IMO !
My 22' with lift keel supported by trunking & purchase wire has a hull bottom 1" + thick.
Even the Carter 30 I had, which I later thought a bit fragile in some ways, had a hull around 25mm around the keel area - and a ladder like thick girder set-up in the whole bilge to support it.
My 22' with lift keel supported by trunking & purchase wire has a hull bottom 1" + thick.
Even the Carter 30 I had, which I later thought a bit fragile in some ways, had a hull around 25mm around the keel area - and a ladder like thick girder set-up in the whole bilge to support it.
NormanS
Well-Known Member
Don't you find it quite frustrating when there are two current threads on exactly the same subject? 
Seajet
...
Not really, I'm not exactly going to break my arm going from one to the other; might show how significant the subject is though.
BlackPig
N/A
How can this keel fall off. It is made as one, no bolts, not stuck either.
DJE
Well-Known Member
So has the bottom fallen out of the market for Oysters?
- I'll get my coat!
- I'll get my coat!
DownWest
Well-Known Member
He is saying it seems to be a hull failure, not attachements breaking, so could happen to an encapsulated keel.
15mm???