Folded float damage to main hull

including Amas (Floats), Akas (Beams) , Swing Wing system and all other hull related issues.
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Mal
Posts: 83
Joined: Thu 02 Nov 06, 16:48
Your Country: Wales

Folded float damage to main hull

Post by Mal »

The previous owner of my boat pointed out a small repair on the underside of the main hull overhang, i.e. directly under the saloon side lockers below the windows. He had been moored folded against a dock when a large fishing boat went by at speed, and the resulting wash made the float hit the underside of the hull overhang.

I bought the boat from him in 2004, and the repair held until this year, when I could see cracking in the gel coat in the area. The repair had been done with polyester filler and glass, so was going to fail eventually, so I have now cut away affected areas, and repaired using epoxy resin, filler, and glass.

With the boat out of the water, it was possible to see that it was the raised moulded circular surface of float deck that is under the end of the main front crossbeam that actually strikes the horizontal hull overhang when folded. I checked the port side, too, and found very slight indentations there in the same place, but nothing requiring repair.

To reduce the possible future damage caused by GRP float deck hitting GRP main hull, I have fixed a Treamaster pad to the underside of the main hull overhang. This should help absorb any slight 'grinding' effects of float against hull

The Treadmaster pads are sold as ready shaped, self adhesive, and in different step sized pieces.

Might be worth checking your own boats to see if there is any marks in similar place to mine;- exactly under the upright between the two saloon windows.

Image Please click on the photo to see it enlarged!
DF920 Pelican, Swansea
roby
Posts: 28
Joined: Mon 19 Apr 10, 21:29
Your Country: italy, brescia, garda lake

Post by roby »

the same thing happend to the boat i'm going to buy. so i think it will beimportant to advise not to leave the boat folded in a place too small !
Diana
Posts: 29
Joined: Tue 13 Apr 10, 12:45
Your Country: Hampshire, UK
Sailing Area: Europe

underarm cracking

Post by Diana »

We have had exactly the same problem so I imagine this is not uncommon. We had repairs done to all four areas last winter and planned to get some stainless plates made up to protect the area and spread the load. But the metalworker never got round to doing it and then the boat was launched and it was too late. I think your solution of treadmaster sounds better though so we may do that this winter. Our damage seems to have happened when we have been folded ready to motor into our marina whose entrance is very narrow. All it takes is a boat doing enough speed to create a wash which whacks the amas up against the water stays trapping them into the underarm area and the damage is done. It also bruises the grey trim piece around the ama deck to hull joint.
extravert
Posts: 15
Joined: Tue 20 Feb 07, 11:58
Your Country: UK,Chester

Post by extravert »

Me too. Punched a hole in the outer layer of the fibreglass. An expensive repair. Now I do not pull the floats all the way in to their stops when folding. Instead I pull them in 10cm short and lock them in place with the float lines.
Mal
Posts: 83
Joined: Thu 02 Nov 06, 16:48
Your Country: Wales

Damage by floats to main hull overhang.

Post by Mal »

Good idea Extravert.

You can also hang a fender down the inside of the float hull before winching in, and this cushions things to some degree. However, the damage is mostly caused, I think, by up and down motion of the float, rather than in and out. I don't know if either of our solutions helps there much?

Also, to be honest, there's so much going on when winching the floats in, and I'm so knackered, that I don't really have the inclination or energy to be mucking about on the float trying to hang/tuck a fender down the inside gap!
DF920 Pelican, Swansea
roby
Posts: 28
Joined: Mon 19 Apr 10, 21:29
Your Country: italy, brescia, garda lake

Re: Damage by floats to main hull overhang.

Post by roby »

i have the same problem. i notice that the right float does not clos well, i try and controll with the boat out of water. The left flot goes down to the main hull so the boat can stand up the floting teflon support. The right does not go so deep and hit the border of the main hull. I asked to quoring to controll my boat, because i canrepair the main hull but i don't know how to make the secon floting egual to the left side.
if some one can help me.
http://gallery.me.com/gattinoni/100044
here some picture
ciao e grazie
buckle.roger
Posts: 73
Joined: Sat 07 Jun 08, 15:43
Your Country: spain,benissa/alicante

Post by buckle.roger »

Hi Guys

The damage to the main hull were the amas hit can be avioded very easily,
Drill a new hole in the saftey bars which holds the amas out a little, mine is such that I can open the hatches when folded, then if leaving the boat for any length of time or in big winds just drop a large fender behind the forward beam to stop it folding in any further , this is no big deal.

As regards being 'knackered' after folding , there have been many threads on this but it is a one hand on the winch handle job If all your machanical pivots are Ok then you first pull slack rope though the back stays, (it is very difficult to pull rope though a 4 to 1 block the wrong way) AND you fit 8mm Dyneema for the 10mm is too big in my opinion for the various turning blocks, and is around 3000kilos breaking strain and as the jammers are only rated at 500 kilos should not be a problem, this has transformed my boat.

While I am on a roll I also noticed on the 28 the back stay is 8 to 1 , I have done this on my 920, just replace the short fixed wire that takes the current 4 to 1 block and put on big block , take a line from the ama back stay fixing piont to the new block and down to the old 4 to 1 block, hey presto 8 to 1 and I can now after unfolding WITH ONE HAND pull in the back stays to sailing tension also by hand, no winching required.


I also wold like to see a 920 with the 28 heads arangement

I hope this helps

roger
roby
Posts: 28
Joined: Mon 19 Apr 10, 21:29
Your Country: italy, brescia, garda lake

Post by roby »

ok how to prevent a damage to the main hull, but why the hamas damage the hull ?, it's a wrong project, or a wrong assembly of the float. it will be nice if the quoring can help us.
i,m still waiting for a response from the builders, as i have more information i'll share with you.
Mal
Posts: 83
Joined: Thu 02 Nov 06, 16:48
Your Country: Wales

Folded Float Damage to Main Hull

Post by Mal »

Buckle Roger;- I like your idea of drilling another hole in the tube to hold the floats further out;- better than keeping them out with tension on the outhaul/inhaul line. Following an earlier post, I've already bought uprated 8mm Dyneema, but have not fitted it yet. Hope this makes winching float in and out easier as you and earlier contributor state.

I'm probably being thick, but I don't quite follow your 8:1 backstay routing:- could you explain again, please?

Finally, yes, 920 with 28 style heads arrangement would be nice, and if folding mechansim on 28 as good as UK dealer claims, that too!
DF920 Pelican, Swansea
buckle.roger
Posts: 73
Joined: Sat 07 Jun 08, 15:43
Your Country: spain,benissa/alicante

Post by buckle.roger »

Hi

One point after drilling a new hole to hlod out the amas it is still possilbe for the foraward arm to be push in and the ama bang the hull, you still need to drop a large fender behind the forward arm after folding, very easy. I only use the fender if big winds are forcast or I am leaveing the boat for any length of time.

The 8 to 1 back stay. I saw this on a photo of the 28 , cant remember were. Leave the existing arangement as is but remove the short wire stay which the current block is attatched to the back stay, put is its place a large block fitted to the 'd' ring on the back stay, noe attatch a nice 10mm rope to your orijinal block, tacke it through the new block on the back stay and fix down on the ama were the original lower block is still attatched, It is so easy if you look at a pic, but this simpley doubles the 4 to 1 arrangment.

I hope this is a little clearer

Good sailing
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