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Check your thu-hulls

Posted: Tue Apr 13, 2021 8:53 pm
by Ozzie
Driving back from the mooring today there was a lot of activity in Belmont Bay near the jetty with bulk rubberneckers on the shore. What looks like a local Bertrand Cruiser had sunk and was being craned to the surface by the local mooring contractor.

I would hazard a guess and say it’s likely this was a failed through hull fitting or head stop cock from what I’ve read. My only such fitting on Spritzig II was a paddle wheel speed sender to the bulkhead speedo. It came with a blank that was screwed in and sika’d on day one of mooring. Anyone have old marine head outlets ?
Scary stuff!!
Scary stuff!!

Re: Check your thu-hulls

Posted: Thu Apr 15, 2021 6:38 am
by Andrew
G'day Ozzie, Thanks for the reminder. Definitely watch and maintain those through hulls, especially if moored. More so if they are metal (bronze or galvanized steel) or very old plastic. Look for signs of corrosion or cracks in the plastic.

No through hulls in the head area on Teria. But do have two black plastic ones down aft in the cockpit lockers, paddlewheel (ex speed/distance log) and blank for something long gone (sounder?). (they cut square hand holes through the locker deck and foam to fit them, screwed/silicone aluminium access hatches over. Aftermarket so could be fair bit younger than boat, but they are at least 20-30 years old. remember paddlewheel logs were the thing in the 1980's, anyone know the history of these devices?) Do check them occasionally, never a drop so just leaving them there until they play up, worst mine could do is flood one of the floatation tanks hand access holes a bit and soak the foam. then the easiest thing for repair is replace with a new plug bedded down in silicone caulking. (perhaps one could even be used again and retrofitted as a fish-finder transducer?)

Re: Check your thu-hulls

Posted: Thu Apr 15, 2021 8:30 am
by snoopebj
Yes Andrew all the through hull fittings on the Investigator seem to be on the lower transom. Wow paddle-wheel log - that’s a piece of 80’s analog nostalgia. Would match my blue tartan upholstery perfectly. Maybe a promising new topic there ? I have sailing books from 70’s and 80’s full of analog gadgets.(and blue and orange tartan upholstery).
Anyway
I forgot to screw in that port locker drain plug last trip something to add to my check list. No harm done though as its just on water line and I always have water in that port locker due to rain leaking in (boat parked in road).
The lower rudder pintle is another weak spot for letting in water.
Also my depth sounder transducer and then there’s that main drain plug in the middle of lower transom. Never used (un necessary?)
Talking to keel boat owners though and we’re much better off. Stuffing boxes, prop shafts, sea cocks, etc etc.
I have a float switch / bilge pump connected directly to battery by-passing the switch panel which I arm when I put my boat in the water. (on check list)
Thanks Ozzie for increasing my paranoia again. 😩

Re: Check your thu-hulls

Posted: Thu Apr 15, 2021 10:25 am
by Ozzie
Sorry guys :oops: i worry too much sometimes :)

It’s funny though, my mate who had the Court 750 bought it as a fixer and as the marine head had been binned decided to remove the glassed in pipes and glass over the holes. He said they pretty much fell off in his hand :o and was glad it didn’t still have the marine head still attached. It would have been a disaster in waiting.

The speed log tube in Spritzig II Is very solid but I’m careful only to put soft stuff like clothes, PFDS and towels in that locker. If I trailered I’d not want anything heavy like a tool box bouncing on top of the tube. My locker drains are usually out to let out fuel fumes and rain on the mooring. I should keep the starboard one in when sailing but I’m a lazy basket and they are usually high enough to not be an issue other than in rough water.

The cruiser in the above pic was tied to the jetty yesterday arvo so it’s ok. Hate to think what water did to the interior and engine.

That reminds me to ask does anyone anywhere have personal or second hand knowledge of an investigator filling up and the efficiency of the air chambers ?

Re: Check your thu-hulls

Posted: Sat Apr 17, 2021 7:45 am
by snoopebj
I recall a certification test done on the Investigator many years ago where the self-righting and capsize capabilities were actually carried out. I did a check on Ray’s magazine library and John Crawford’s library but no luck.
You could do it yourself Ozzie.😲
Tell me how you got on.
If we don’t hear from you then we know the Investigator failed.😆

Re: Check your thu-hulls

Posted: Tue Apr 27, 2021 5:12 pm
by Andrew
No one's ever going to be game enough for the "sink" test..😄 just hope the designer did his sums right,

Perhaps a stripped clean hull (undergoing full refurbishment) with extra weight to represent rig, motor and supplies, could be tossed in with the bung out ! Just tie a good tow rope on first! Maybe a lift bag handy, you wouldnt want to be on "Aussie Salvage squad"! 🤯

Re: Check your thu-hulls

Posted: Tue Apr 27, 2021 11:21 pm
by snoopebj
Good luck with that test Andrew😆
I’m not good with maths stats etc but found this info that might mean something.
Capsize Screening Formula (CSF):
Designed to determine if a boat has blue water capability. The CSF compares beam with displacement since excess beam contributes to capsize and heavy displacement reduces capsize vulnerability. The boat is better suited for ocean passages (vs coastal cruising) if the result of the calculation is 2.0 or less.”
The Investigator 563 CSF is 2.51 according to specs below.
https://sailboatdata.com/sailboat/investigator-563

No idea of the meaning relevance or accuracy of these figures.
From my personal experience comparing the Investigator with sailing other keel and t/s boats offshore it is very stable predictable and confidence building.

Re: Check your thu-hulls

Posted: Wed Apr 28, 2021 2:53 pm
by Ozzie
I have checked that sailboat data Emrys. The comfort factor is noted as 10.46
83ACC3D5-5F21-444A-851F-02800AC5F682.jpeg
By adding my boogie board backrest I can increase this to 13.42 give or take 0.4 either way depending on the temperature of my beer.
5561575D-E5B2-4FFB-B12A-829263E454F3.jpeg
5561575D-E5B2-4FFB-B12A-829263E454F3.jpeg (20.96 KiB) Viewed 5393 times
...as you probably gathered, I have done nothing useful today....

Re: Check your thu-hulls

Posted: Wed Apr 28, 2021 3:19 pm
by snoopebj
😂 haha
That CF of 13.42 is taking into account the angle of the dangle is inversely proportional to the throb of the knob when the sun is directly overhead.
TSP would be proud of us. Lots of serious number crunchers there.

Re: Check your thu-hulls

Posted: Wed Apr 28, 2021 5:26 pm
by Geoff
:D

Even with twist and pike the degree of difficulty looks very minimal.