Island Time 1,232 Posted December 4, 2016 Author Share Posted December 4, 2016 True, KM, but I agree with NZL1 - there a a hell of a lot of these boats out there sailing, both local, coastal and offshore. Most have no issues at all. People talk about "bonding" the matrix/grid to the hull. "Bonding" is "Glue". Well GRP is mostly "Glue" and ply is "Glued" together. ALL boats have bonding systems, regardless of construction material - metals are welded, timber is glued, etc etc. The Matrix/Grid/Liner is "Bonded" to the hull and it should become one structural component. Sometimes this is the section that failed, sometimes tearing it apart removes some hull as it goes. Any structure can be broken given the required forces. Bene claim that their "glue" is actually stronger than tabbing. Debatable I think. What I see as a weak point in these designs (my own boat included) is that the keel bolts don't go through the floors (frames), but are beside them instead. The structure would, IMO be significantly stronger if the bolts went right through everything. That being said, I hit a large log at 7 knots, almost completely stopped the boat dead. Impact was 400mm down the front edge of the keel. There was virtually no damage at all, just a crack in the leading edge of the keel, vertical, about 200 mm long. No movement in the floors, keel bolts, or the keel/hull joint. They ARE strong, but as I said, anything can be broken. My boat also has 14 Keel Bolts. Some have 5.... I suggest ANYONE looking at a 2nd hand boat gets it surveyed by a competent person, and buy a boat in good order! Quote Link to post Share on other sites
harrytom 642 Posted December 4, 2016 Share Posted December 4, 2016 I.T,had a look at my keel bolts the other day after bouncing on a rock(should of known better) mine are bolt through floors 1 at front floor 2 in next 2 in next aft 1 6 bolts in total all 1/2in 12mm on cav 26ft so feel there is no problem there. Regardless of construction should be able to take a fair knock or 2 without major damage.. on a side note do beney sail to windward?see a hell of a lot motoring Quote Link to post Share on other sites
Guest NZL1 Posted December 4, 2016 Share Posted December 4, 2016 All most every charter boat is French, even the rafts. The bucks baby, it's all about the bucks. The French taxpayers very heavily subsidise boats exported for charter to the point no one else can get any where close to them on cost. It's a simple choice for the bean counters and has bugger all to do with anything else. It would be interesting to see what would happen if the subsides were removed. I suspect the builders are now so reliant on them it would be carnage at the likes of Benny if they did. thats true Seal. But companies like Navegare dont just buy on price. They buy on the other big $$$ costs in thier buisness. Namely reliability and maintenance. Beneteaus are as good as any other production boat from any country. A kiss from a rose! Or Crazy?.... Quote Link to post Share on other sites
Battleship 100 Posted December 4, 2016 Share Posted December 4, 2016 The First Series sail to windward well, very good boats (apart from the keel floor issue), the Oceanis series are pigs in my opinion, pretty much motor sailors but very roomy and comfortable below. 1 Quote Link to post Share on other sites
Guest NZL1 Posted December 4, 2016 Share Posted December 4, 2016 The First Series sail to windward well, very good boats (apart from the keel floor issue), the Oceanis series are pigs in my opinion, pretty much motor sailors but very roomy and comfortable below. Yes that sums them up. But... they actually sail very good to windward once you throw away the Cruising headsail arangements and put proper race oriented headsail configurations on. Most of these cruisers are good upwind but are heavily compromised by rolling headsail setups. Put one of these cruising set ups on a race yacht and your windward performance will be compromised quit a lot. Quote Link to post Share on other sites
too_tall 15 Posted December 5, 2016 Share Posted December 5, 2016 The amount of french built production yachts I have seen in marina's around the world which are regular ocean voyagers, says that they must be pretty OK all rounders and obviously do not sink or fall to bits as regularly as the nae-sayers would have you believe. I have seen all sorts of yachts suffer major structural issues, made of all sorts of materials. I have seen a yacht which bumped into something hard at 4kn do damage which I suspect wrote it off, and have seen the exact same make and model hit something equally as immovable at what I assume was around 8kn ( we were doing 6kn and they were catching us as about walking pace ) and the worst casualty was the poor wife who was thrown over the bow and her husband could not get the boat off what he hit to rescue her from the current. We collected her, towed him off once the tide came up a little more and he made it back to the boat lift without the bilge pump coming on once. Lifted her out, put her in a cradle and I later heard from him that the only damage was to the bulb and his pride once his wife started telling all their friends... Quote Link to post Share on other sites
Frank 157 Posted June 3, 2017 Share Posted June 3, 2017 Interesting topic for me as I am considering a Bene Oceanis 405 of 90's vintage. I currently have a self built Carpenter 29 which goes to windward quite well. I have sailed a Dufour 43 or thereabouts in Noumea, it was a dog on the wind but the interior space was amazing, To be fair it had a shortish keel and for the most part I think it just needed more grunt in the rig. There are so many opinions on the internet about the grid/Liner method of construction its hard to sort the truth from the noise. I'm curious as to why someone has not evolved a cost effective technique for repairing disbonded liners. Methods that come to mind are 1. Removing the flat sections between the "Girders" or "Floors+ leaving a Top Hat section with a flange that can then be Tabbed back on to the the hull. 2. Trepanning a large circle of material between the raised sections and localised tabbing to "Stitch" the grid to the hull , could work for smallish areas. 3. Applying a vacuum and infusing epoxy resin into a disbonded area, an acetone wash could be applied possibly. 4. A mix of the above. I would be interested to hear from anyone who has experience in this area ? Quote Link to post Share on other sites
Frank 157 Posted June 4, 2017 Share Posted June 4, 2017 Not sure how much of a problem it is given the numbers of boats produced with this method. The reason that bolts dont usually go through glass floors is that the they are not solid but top hat construction. Timber floors take the compression and the floors spread the load to stringers or hull as the case may be. On a glass boat the "keelson" is solid and and can withstand huge bolt tension, the layup spreads the load to the floors etc. Grids are quite elegant design solutions provided they are bonded correctly given the huge surface area. Mmmmm, Interesting, I figured the top hat sections were almost certainly hollow, your comment that it is an elegant design solution is an interesting and I'm sure accurate perspective. The problem is I guess that we never see a posting from the Naval Architect who designed the installation, explaining the philosophy. However perhaps what is shown is that the solid floor approach may be more damage tolerant in terms of groundings etc. I did hear from an NZ broker yesterday of a production yacht that failed the pre-purchase inspection quite recently. It was due to a significant area of liner disbonding on the port side. The boat otherwise presented well. Quote Link to post Share on other sites
Dtwo 157 Posted June 7, 2017 Share Posted June 7, 2017 The main issue with grids is the bonding or gluing process. Its a one shot affair, it may work perfectly for 99 boats but on the 100th where some low wage worker under or over catalysed the resin... and it's very difficult to survey properly. I dont like them for that reason alone. My understanding (based on extensive work with Benes in the 80s, so may be out of date) is that the "bonding" is a polyurethane. While that may well be fine and approved, giving no problems for most yachts, I personally would not be comfortable with it on an older boat. I am not certain if the glues used would degrade over time, or fatigue after X collisions. I am also guessing that partial failure may occur with no sounds or visual clues. As I have tried to stress here, it is a personal opinion. Feel free to buy and sail whatever craft you want. My boat is a production boat, just not French. Don't ask me about Bavarias either, coarse language may offend. Quote Link to post Share on other sites
Myjane 40 Posted June 8, 2017 Share Posted June 8, 2017 What sort of boat is it . Quote Link to post Share on other sites
Addem 94 Posted June 17, 2017 Share Posted June 17, 2017 Reminds me of another book : Breaking Seas by Glenn Damato, a self confessed obese computer geek who decided to escape the rat race and bought a boat to sail around the world. . Very amusing about what not to do. He only made it to Mexico - the boat had a horribly leaky hull/deck joint. First time I'd heard if it. Other funny things he did: he engaged an all women crew but had installed a composting toilet which needed liquids kept separate from the solids which the girls refused to do and it ended up dumping everything all over the cabin. The girls jumped ship after he turned down a proposition from one who had the hots for him but was larger than he was. He had to return single handed, motor failed on a Lee shore and in the end He abandoned the boat and headed back to his job with his tail between his oversized legs. Quote Link to post Share on other sites
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