rogerthebodger
Well-Known Member
I know why...
I thought you said you were going to put me on ignore.
Through Hull backing pad, how big?
- Thread starter wipe_out
- Start date
I thought you said you were going to put me on ignore.
PaulRainbow
Well-Known Member
Better yet, put me on ignore then you won't feel the need to keep sticking your nose in.
rogerthebodger
Well-Known Member
Why should I not poke my nose in. I ask again is it against forum rules.
We have a constitutional right of freedom of speech with the restriction of hate speech, I think UK also has the same freedom and restriction from the EU bill of rights.
We also have the constitutional right of freedom of association so I can associate with whoever I wish and the right of non association
Too much fun, just like pvb.
pvb
Well-Known Member
You have also agreed to abide by YBW's terms and conditions, and I'd draw your attention to 4.3 and 4.4
rogerthebodger
Well-Known Member
They also apply to you but its up to the Moderators to decide it I or you have breach a of the YBW's terms and conditions.
There is also a report button on each posting to if you or anyone thinks I started any any rude or abusive messages you are free to report to the moderator
| 4.3 | Do not post rude or abusive messages - including personal attacks on other |
| 4.4 | Do not post defamatory or other insulting or inappropriate content (see clause 4.12) |
| 4.12 | Content that would not ordinarily appear within the editorial pages of the printed magazines |
So what are you doing to do report me or not your choice, or just accept it as normal forum banta and discourse and move on.
Neeves
Well-Known Member
To bring the thread back on track but picking up on the recent part of the debate
Our Lightwave is glass below the waterline and cored above. I've never added a through hull above the waterline and those we have added below the waterline commonly need a backing plate to offer a flat surface inside the hull against which the flange is tightened. Anything above the waterline that we have added has the core removed, backfilled with resin and backing plates applied (as Roger describes). The plates might be multiple glass layers or stainless steel (and for our bowsprit - both). We added tracks and a single winch (we cross sheet) on the cabin roof for a 150% genoa and in the build a backing plate (or reinforcement) was, conveniently included in the moulding consisting of 10mm ply and a 5mm aluminium plate for both the track and winch.
But cored above and all glass below the waterline is not uncommon and is quite accepted. Our cabin sole is roughly the waterline (without our mini keels we would draw roughly 300mm - I'm guessing the keels are about 700mm - as we draw 1m).
Jonathan
Our Lightwave is glass below the waterline and cored above. I've never added a through hull above the waterline and those we have added below the waterline commonly need a backing plate to offer a flat surface inside the hull against which the flange is tightened. Anything above the waterline that we have added has the core removed, backfilled with resin and backing plates applied (as Roger describes). The plates might be multiple glass layers or stainless steel (and for our bowsprit - both). We added tracks and a single winch (we cross sheet) on the cabin roof for a 150% genoa and in the build a backing plate (or reinforcement) was, conveniently included in the moulding consisting of 10mm ply and a 5mm aluminium plate for both the track and winch.
But cored above and all glass below the waterline is not uncommon and is quite accepted. Our cabin sole is roughly the waterline (without our mini keels we would draw roughly 300mm - I'm guessing the keels are about 700mm - as we draw 1m).
Jonathan
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Neeves
Well-Known Member
I think the concept the coring should not be used below the waterline and quoting learned volumes stating same is - well dated.
Technology has moved on, dramatically.
I'm not sure how members think one off yachts are built - they have no mould, for a one off, and building a mould would be extortionate. The reason a Jenny or Benny uses a mould is because they are building multiple copies and its quicker and cheaper to use a resin gun than building with foam and laying on glass sheets.
Most are built, upside down, from foam, faired, glassed, faired again and then turned right way up. In the initial stages the bulkhead are installed first and then the hull built up using foam planks - not much different to old fashioned boatbuilding techniques. The interior is then fitted out and deck attached. If you think back - this is not much different to the build of a Mirror dinghy and I vaguely recall a similar technique was used to build a small cruising yacht - sponsored by PBO (not sure of this???).
Most of the work was in the fairing but you can rent fairing mchines now to do the hard yakka.
There is another technique, where the yacht (castamaran) is moulded in pieces which you then glue together - but I don't know how much foam is used, look for a Fusion 40. You do need a big shed - however you do it.
There is a whole industry devoted to such production technique and the foam is, or can be, delivered in sheets that are already routed out held by locations where the router was stopped - its like a giant balsa wood model. You can buy foam already coated with fibreglass or carbon and already coated with which veneer interior you have chosen. You can use different foams in different locations for strong points (or not). They used to use the same technique 'earlier' with balse and the shed in which our Lightwave was built had housed a 50' cat that was built from a combination of ply, balsa and foam. Balsa and ply have been 'moved out' and virtually all 'one offs' are now all foam.
Its a big business in Australia, check our Schionning designs and a company called ATL, who work with Wests, sell all the foam, glass and resin and will deliver pre cut (routed) sheets 8'x4' to your specific design. You can build at home or have the vessel built by a professional boat builder. Schionning and Grainger are both internationally well known multihull designers both design based on the methodology I try to describe. In the UK John Corby will, or would have, use(d) the exact same technique
Dogmatism has no place here - technology is constantly moving. The learned tomes being quoted have not lost their value - but you might need to cherry pick especially for carbon and the newer resins.
Jonathan
Technology has moved on, dramatically.
I'm not sure how members think one off yachts are built - they have no mould, for a one off, and building a mould would be extortionate. The reason a Jenny or Benny uses a mould is because they are building multiple copies and its quicker and cheaper to use a resin gun than building with foam and laying on glass sheets.
Most are built, upside down, from foam, faired, glassed, faired again and then turned right way up. In the initial stages the bulkhead are installed first and then the hull built up using foam planks - not much different to old fashioned boatbuilding techniques. The interior is then fitted out and deck attached. If you think back - this is not much different to the build of a Mirror dinghy and I vaguely recall a similar technique was used to build a small cruising yacht - sponsored by PBO (not sure of this???).
Most of the work was in the fairing but you can rent fairing mchines now to do the hard yakka.
There is another technique, where the yacht (castamaran) is moulded in pieces which you then glue together - but I don't know how much foam is used, look for a Fusion 40. You do need a big shed - however you do it.
There is a whole industry devoted to such production technique and the foam is, or can be, delivered in sheets that are already routed out held by locations where the router was stopped - its like a giant balsa wood model. You can buy foam already coated with fibreglass or carbon and already coated with which veneer interior you have chosen. You can use different foams in different locations for strong points (or not). They used to use the same technique 'earlier' with balse and the shed in which our Lightwave was built had housed a 50' cat that was built from a combination of ply, balsa and foam. Balsa and ply have been 'moved out' and virtually all 'one offs' are now all foam.
Its a big business in Australia, check our Schionning designs and a company called ATL, who work with Wests, sell all the foam, glass and resin and will deliver pre cut (routed) sheets 8'x4' to your specific design. You can build at home or have the vessel built by a professional boat builder. Schionning and Grainger are both internationally well known multihull designers both design based on the methodology I try to describe. In the UK John Corby will, or would have, use(d) the exact same technique
Dogmatism has no place here - technology is constantly moving. The learned tomes being quoted have not lost their value - but you might need to cherry pick especially for carbon and the newer resins.
Jonathan
rogerthebodger
Well-Known Member
I agree with Jonathan
Technology moves on at quite a pace both in material and in production techniques.
Having been interested in build a big boat for many years but either not having the money, time or space was not able to so ended up in buying a boat that needed TLC and fixing it up.
I studied most of the DIY methods over the years I found that a couple of designers specialised in the DIY build designs and published books with reference to the various methods.
Bruce Roberts have produced designs that could be built in various materials and techniques available to the DIY er. All have some form frame technique with the GRP material using a temporary build frame and some form of material to hold the shape like foam or C glass before then resin stage.
The foam method has foam stitched all over temporary frame including below the waterline then glassed over. Once removed from the temporary frame then foam is removed from the area below the floor level keel and skeg. The inside is then glasse over. Removing this foam is a time consuming and unpleasant job
In a production situation where a mold is used the outer layer of GRP and gelcoat is put in the mold and the foam inserted after but only down as far as necessary, any more is just adding cost . Also adding to foam to the GRP required makes it more difficult to get a good adhesion to the GRP than adding GRP to foam as in the DIY approach.
I have seem several mold produced foam core boats where the outer layer of GRP brake away for the foam due to the bow loading this core GRP adhesion is very important for the strength of the hull.
It only those who have either built their boat hull of studied self building a boat hull that really understand the detailed techniques.
Technology moves on at quite a pace both in material and in production techniques.
Having been interested in build a big boat for many years but either not having the money, time or space was not able to so ended up in buying a boat that needed TLC and fixing it up.
I studied most of the DIY methods over the years I found that a couple of designers specialised in the DIY build designs and published books with reference to the various methods.
Bruce Roberts have produced designs that could be built in various materials and techniques available to the DIY er. All have some form frame technique with the GRP material using a temporary build frame and some form of material to hold the shape like foam or C glass before then resin stage.
The foam method has foam stitched all over temporary frame including below the waterline then glassed over. Once removed from the temporary frame then foam is removed from the area below the floor level keel and skeg. The inside is then glasse over. Removing this foam is a time consuming and unpleasant job
In a production situation where a mold is used the outer layer of GRP and gelcoat is put in the mold and the foam inserted after but only down as far as necessary, any more is just adding cost . Also adding to foam to the GRP required makes it more difficult to get a good adhesion to the GRP than adding GRP to foam as in the DIY approach.
I have seem several mold produced foam core boats where the outer layer of GRP brake away for the foam due to the bow loading this core GRP adhesion is very important for the strength of the hull.
It only those who have either built their boat hull of studied self building a boat hull that really understand the detailed techniques.