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Thread: Rebuilding a Carvel Hull - Please Help!

  1. #36
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    Keeping her as a trailer sailer/ dry sailer to be used a few times a month for day trips or the occasional week long cruising adventure is the only possible option.

    I went down the sheathing rabbit hole on a number of threads here and elsewhere as well as the WEST system repair guide and the Gougean Brothers book and have decided it’s probably not the best option? If I’m going to spend thousands of dollars and lots of time I would really like something that is guaranteed to last a while. I’m still open to the idea though so please correct me if I’m wrong. Seeing as she will be an open boat that has been splined and will not spend much time in the water at all and not for long periods of time does this make her a better candidate for sheathing?
    Carvel hull, on and off a trailer, swelling and drying out many times a year....... Eventually (fairly quickly I'd guess) she won't take up (swell to the point of being watertight) any more. If you're day sailing, you'd be lucky if she took up before you got back to the ramp. Lots of pumping for a day on the water.....

    I'd say sheathing is the only way to go. With the splining already done, if its in good nick, a good chunk of the work is done for you. Sheathing also saves you jobs elsewhere, as others have described.
    It's all fun and games until Darth Vader comes.

  2. #37
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Here's a bit of rough progress with the paint removal. I ended up using a combination of heat gun / scraper and sanding disc on a 3 inch grinder (all I have access to at the moment).
    On the outside the heat gun works pretty well in removing the bulk, then the grinder with the sanding pad, finishes the job very quickly. Unfortunately, the 40 grit disc did get clogged up pretty quickly and stopped working as well. On the inside, the top areas have been coated with tar and the bilge area with red lead paint before being painted over. The paint on top of the tar peels straight off with the heat gun. The red lead paint is more stubborn. I haven't had the grinder inside yet.

    The planks seem, for the most part, pretty good. The splines in the topside planking, are pretty good also. There are a few below the waterline that are loose. And as you can see in the photos a few areas where the planking has split apart by a few mm.

    Out of the 70 ribs I, counted at least 33 that need fixing or replacing. And I think all the fasteners are finished.

    The gunwales have had severe termite damage, they are made from three pieces of timber and I think the entire inner most piece would need replacing.

    The centreboard case seems to be pretty solid, or could be easily repaired to be solid.

    The transom has a few cracks, one of which being pretty wide, but is otherwise solid.

    One of the floors also has termite damage and would need replacing, the others are good.

    The 'bilge stringers' (?) are solid.

    The keel, where the bronze rudder mount is attached might need some attention. But I think the backbone is otherwise pretty good.


    18.jpg19.jpg20.jpg22.jpg
    17.jpg
    Last edited by Ruey; 10-17-2020 at 07:46 PM.

  3. #38
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Some more images.

    21.jpg23.jpg24.jpg28.jpg26.jpg

  4. #39
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    So I still don't know whether or not to move forward, and if so what direction to take.

    To me, (with absolutely no experience or idea) it seems so counterintuitive to spend the time/ money repairing her traditionally as a carvel boat and then use modern construction techniques over the top (epoxy /cloth seeming to be pretty incompatible or cold moulding, more so, but still not completely compatible).

    I've estimated the cost of refastening her with screws to be about $1000 AUD for silicone bronze or about half that for brass.

    I've come across a few examples where the frames and fasteners are left un-repaired, then the boat sheathed in either epoxy / cloth or cold moulded.

    https://www.denmanmarine.com.au/teal-i23/

    https://www.offcenterharbor.com/2013...xy-eric-blake/

    https://www.offcenterharbor.com/vide...life-charlena/

    Would this be an option?

    1.) Brace her as well as possible then turn her over ( I think she would be strong enough for this due to the extra metal straps and temporary bracing).

    2.) Strip all paint, fair planking, repair splines or fill gaps with thickened epoxy.

    3.) Sheath using epoxy/ biaxial cloth or cold moulded double diagonal veneer + plywood sheathing over transom.

    4.) Turn her back over and remove frames, paint and tar.

    5.) Fill seams with thickened epoxy.

    6.) Coat entire inside with epoxy (and cloth)?

    7.) Glue in laminated frames or plywood bulkheads? + Epoxy fillet any joins.

    8.) Repair / replace gunwales at some point.

    8.) Enjoy!

    This way there is no inaccessible fasteners, the carvel planks don't get wet, the boat is trailable and happy to be kept dry for months at a time and the extra weight is offset by the removal of the deck.

    Could there be the potential to make buoyancy tanks out of plywood, and even water or sand ballast boxes instead of using lead id the inside of the hull was sealed?

    Or am I completely mad with this whole idea?

    I understand that encapsulating wood with epoxy can lead to water getting trapped in leading to rot, but would not that be the case for every plywood/ strip planked boat that is encapsulated too? Lots of people seem to be building them.

    Thanks

  5. #40
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    I tend to think you’re heading in the right direction Ruey, albeit with a few changes and maybe in a different order. Others may come in with better or at least different thoughts but I don’t think you should have any concerns about sheathing her, it will just be the preparation that is key.

    I would continue stripping out all of the paint and replace the frames before doing anything else - though don’t rip them all out at once. Do each alternate frame or maybe even every third frame before going back and doing the same for the remaining frames.

    The idea of gluing in new laminated frames seems sound enough - basically treating it as a new build with an old skin. The difficulty is holding them in place while the epoxy goes off and that’s where the screws come in. Because you’re sheathing her anyway and she’ll be on a trailer you could use 316 stainless screws or ......... you could have a go at copper riveting.

    But I suggest replace the frames and then repair your hull where necessary before doing anything else such as epoxying the inside of the hull. IE rather than gutting the hull entirely of frames and possibly losing your shape.


    What ballast do you need? Did the boat have ballast additional to the centreboard - ie assuming the centreboard was either a steel plate or a weighted timber centreboard? If it doesn’t why would you want to add more ballast and essentially change the design of the boat?

    Sealed ply buoyancy tanks are fine and you can include spin-outs to use them for storage and/or to check them.

    Ballast is different though if you do need it additional to the centreboard and you’ll need more sand or water to make up the weight than lead so if you need extra ballast I’d be looking for lead, if not perhaps concrete. Water ballast in modern boats has complex pumping arrangements and a lot of baffles to reduce free-surface effect so I wouldn’t be trying to go down that path.

    lead is 11.4 g/cc, water is 1.0 g/cc (1g/cc = 1 gram per cubic centimetre) - concrete is about 2.4 g/cc
    Last edited by Larks; 10-17-2020 at 09:00 PM.
    Larks

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  6. #41
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Yo need to decide what you want. If only the outside is sheated then either the sheating is structural or you replace the existing frames. If the inside is also sheated the frames are redundant and you only need a few bulkheads or ringframes. Structural fberglass sheating is expensive, cold molding is cheaper.

  7. #42
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Do NOT use brass fixings. They will corrode to dust in no time at all.

  8. #43
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Larks View Post
    I tend to think you’re heading in the right direction Ruey, albeit with a few changes and maybe in a different order. Others may come in with better or at least different thoughts but I don’t think you should have any concerns about sheathing her, it will just be the preparation that is key.

    I would continue stripping out all of the paint and replace the frames before doing anything else - though don’t rip them all out at once. Do each alternate frame or maybe even every third frame before going back and doing the same for the remaining frames.

    The idea of gluing in new laminated frames seems sound enough - basically treating it as a new build with an old skin. The difficulty is holding them in place while the epoxy goes off and that’s where the screws come in. Because you’re sheathing her anyway and she’ll be on a trailer you could use 316 stainless screws or ......... you could have a go at copper riveting.

    But I suggest replace the frames and then repair your hull where necessary before doing anything else such as epoxying the inside of the hull. IE rather than gutting the hull entirely of frames and possibly losing your shape.


    What ballast do you need? Did the boat have ballast additional to the centreboard - ie assuming the centreboard was either a steel plate or a weighted timber centreboard? If it doesn’t why would you want to add more ballast and essentially change the design of the boat?

    Sealed ply buoyancy tanks are fine and you can include spin-outs to use them for storage and/or to check them.

    Ballast is different though if you do need it additional to the centreboard and you’ll need more sand or water to make up the weight than lead so if you need extra ballast I’d be looking for lead, if not perhaps concrete. Water ballast in modern boats has complex pumping arrangements and a lot of baffles to reduce free-surface effect so I wouldn’t be trying to go down that path.

    lead is 11.4 g/cc, water is 1.0 g/cc (1g/cc = 1 gram per cubic centimetre) - concrete is about 2.4 g/cc
    Thanks Larks,

    Ok noted about the frames, I would love to have a go a copper riveting but I think I will be working on her by myself for the most part.

    I can't find any information about how much ballast the design calls for normally, but I did read in the handbook for the design, that the minimum ballast allowed for racing was 250 kg in addition to the 6mm steel centreboard. Ok, I will not bother with the water ballast idea, lead or concrete it is!

    Cheers

  9. #44
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by lupussonic View Post
    Do NOT use brass fixings. They will corrode to dust in no time at all.
    Thanks!

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    Default Re: Rebuilding a Carvel Hull - Please Help!

    I would say you are mad taking it on yes. It is whether you and those around you can live with the madness!

  11. #46
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Rumars View Post
    Yo need to decide what you want. If only the outside is sheated then either the sheating is structural or you replace the existing frames. If the inside is also sheated the frames are redundant and you only need a few bulkheads or ringframes. Structural fberglass sheating is expensive, cold molding is cheaper.
    Thanks Rumars,

    I think I need the sheathing to be structural, however I have been advised that I need to replace the existing frames as well. Or at least replace them before I can start the structural sheathing process so the hull keeps it's shape.

    I think I would prefer to cold mold the hull, but I'm a bit worried about the difficulty/ time needed to do so, but I'm yet to make up my mind.

    How much fibreglass would I need to sheath the hull with to make it structural, and what type of cloth would you recommend?

    Thanks
    Last edited by Ruey; 10-18-2020 at 04:55 AM.

  12. #47
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    Thanks Rumars,

    I think I need the sheathing to be structural, however I have been advised that I need to replace the existing frames as well. Or at least replace them before I can start the structural sheathing process so the hull keeps it's shape.

    I think I would prefer to cold mold the hull, but I'm a bit worried about the difficulty/ time needed to do so, but I'm yet to make up my mind.

    How much fibreglass would I need to sheath the hull with to make it structural, and what type of cloth would you recommend?

    Thanks
    I think you’d be complicating things by trying to change too much Ruey - keep it as simple as you can otherwise you start going down a rabit hole of trying to do something that there is no design for - ie trying to work out how far you need to go with glassing to make it structural. Personally I don’t think you want to take on that headache.......and the weight and cost of product that may be involved.

    Rebuild what you have the way it was - ie frame for frame, fix your planks and splines etc and then glass it externally and epoxy coat it internally and paint it so that it can be kept out of the water on a trailer.
    Larks

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  13. #48
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Cold molding sounds like adding a complication for no gain, over just sheathing.

    Any idea what the wood is?
    Looks like cedar splines, but I'd not be surprised if the planking is huon.

    The black lines along the splines says resourcinol to me. If they're solid leave them in, where they are not, kerf along the loose edge and epoxy in a new spline. I think do that before you remove any frames. Lock the hull shape, then remove the frames entirely, for good. Fill the fastner holes with thick epoxy, fair the whole thing and sheath inside and out.

    Any parts you take off, keep, you might need to use them for a template - even termite eaten bits.

    The boat won't live in the water so stainless steel screws will be fine, where needed, I think. But if you're sheathing you'll need very few screws.

    The stern post looks mostly sound, cut out the gnarly bit with those fastener heads and glue in a graving piece. Are those fasteners going through to the stern knee? Looks like they are headed toward the end grain of the keel.... so maybe they held on a fitting once upon a time?
    Last edited by gypsie; 10-18-2020 at 08:11 PM.
    It's all fun and games until Darth Vader comes.

  14. #49
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    Thanks Rumars,

    I think I need the sheathing to be structural, however I have been advised that I need to replace the existing frames as well. Or at least replace them before I can start the structural sheathing process so the hull keeps it's shape.

    I think I would prefer to cold mold the hull, but I'm a bit worried about the difficulty/ time needed to do so, but I'm yet to make up my mind.

    How much fibreglass would I need to sheath the hull with to make it structural, and what type of cloth would you recommend?

    Thanks
    Structural sheating does not need the frames, you are replacing all the transverse strenght and stiffness of the frames with material on the outside. While strenght is not a problem, but stiffness comes from thickness and you need a fairly thick sheating. That's why cold molding is cheaper, you can use fairly thick veneers 4-6mm that build thickness fast. The same thickness with fiberglass consumes a lot of epoxy and glass, it was usually done with polyester. You probably need 10-12mm of sheating for it to be structural. 1mm of glass is approx 1000g/sqm of fiberglass plus the same amount of resin. It is cheaper to convert to a cored construction by sheathing the inside also, that way you only need approx 1mm of fiberglass each side. A biax fabric is what I would use.

    Non structural sheating is two layers of thin (1,5-2,5mm) veneer or/plus 2-300gr/sqm of fiberglass, a woven fabric usually, and is there only for waterproofing, worms, and a little bit of abrasion protection. This requires sound frames to take the sailing loads, otherwise it will rip at the seams. Replacing framing you have two options, steam bent and laminated. Steam bent frames are quick to do, maybe 3 full working days for a team of two people to replace and refasten the whole boat. But you need green wood for steaming, pay for the copper nails and a second person at least for the riveting. Laminating can be done multiple ways, the quickest is to laminate in place glueing and stapling the first veneer to the planking. Cleanup can be a little scary, you need to grind the frame sides in place. Fasteners to the planking are optional.

    Prep time for all methods is equal, the hull needs to be sanded clean inside out, all rotten wood replaced, all splines and gaps glued solid. Temporary bracing is just some strips of ply and transverse wood, this is an already splined boat, it will not loose shape easily.
    What you end up doing is mostly a matter of preference, how you want to work and what result pleases you more esthetically. Local materials availability can also play a role, cold molding structurally is easier when having access to commercial sawn veneers.

  15. #50
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    10 to 12 mm for sheathing?? Maybe on a big yacht, were the original is finished.
    This little number could be done with a couple of layers of bi-axilal cloth in an an afternoon. I did a 15ft hull with a couple of friends in that time. It was double diagonal, rivited with cloth between the layers and dried out for 30 yrs. Beyond the sklll set of the owner to do anything else, like replace loads of cupped thin planks.

    What caught my attention in the early posts, was OZ and on a trailer. Not great for a carvel hull. So, unless you want to spend a lot of time keeping a classic(?) in original condition, it might be better to get her suitable for your intended use, and get out on the water.

  16. #51
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Well, if she was a light double diagonal I would have agreed. But she is carveel and heavy, and we are talking about removing all frames.

  17. #52
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Yesterday I was lucky enough to have my friend's father, who is a shipwright, have a look over her and recommend how I proceed. He has built wooden boats his whole life, mainly fishing trawlers, but he now also restores wooden boats like mine. He showed me his own carvel built boat that has been restored and epoxy/ cloth coated which has been living on a trailer for the last 15 years with no problems. He has another similar carvel boat restored in the same way that also has had no problems. Inspirational stuff!

    He basically suggested what has already been said by larks and others already on this thread.

    Process roughly as follows (not particularly in order):

    Replace timbers running down to keel with solid floors as Nick suggested earlier.

    Steam in new ribs - I've sourced a local mill that can supply green spotted gum and the shipwright leant me his welded steel post to boil / steam them in. He said don't bother with a steam box.

    Replace the innermost gunwale section, again using green spotted gum- he said it probably won't even need steaming, but if it does, it will fit inside the steel post.

    Refasten using 316 SS screws. Probably 8 gauge.

    Use thickened epoxy to seal the gaps in the planking or where the splines have fallen out. Maybe replace splines, I'll decide when I’m closer.

    Also use thickened epoxy to repair the stern post/ keel.

    Add some additional ‘half floors’ secured to the centreboard case and planks to add additional strength for trailering.

    In addition, I also want to add another stringer about in line with the top of the centreboard case to fasten thwarts to. I haven’t thought this over much but I’ll do more research when I get closer.

    Sheathe the outside of the hull with epoxy and 2 oz (I think 600 GSM metric) chopped strand mat. Trowel thickened epoxy into the surface to fill the bumps.

    Coat the inside of the hull with epoxy (including under where the ribs will fasten to the planks, done as they are replaced).

    I’ll post photos as I go for future reference.


    Thanks all!


  18. #53
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by gypsie View Post
    Cold molding sounds like adding a complication for no gain, over just sheathing.

    Any idea what the wood is?
    Looks like cedar splines, but I'd not be surprised if the planking is huon.

    The black lines along the splines says resourcinol to me. If they're solid leave them in, where they are not, kerf along the loose edge and epoxy in a new spline. I think do that before you remove any frames. Lock the hull shape, then remove the frames entirely, for good. Fill the fastner holes with thick epoxy, fair the whole thing and sheath inside and out.

    Any parts you take off, keep, you might need to use them for a template - even termite eaten bits.

    The boat won't live in the water so stainless steel screws will be fine, where needed, I think. But if you're sheathing you'll need very few screws.

    The stern post looks mostly sound, cut out the gnarly bit with those fastener heads and glue in a graving piece. Are those fasteners going through to the stern knee? Looks like they are headed toward the end grain of the keel.... so maybe they held on a fitting once upon a time?

    Yep, the splines are cedar and the planking is huon.

    What do you think about just filling the gaps in the planking with thickened epoxy, and also fixing the stern post / keel where its a bit loose with the same?

    Yep, the fasteners go through to the knee, not sure about a fitting, I think they were flush with the edge of the timber but it has possibly decayed that much over the years?

    Just found your thread on sheathing the 1962 carvel, I haven't had a chance to go through it properly, but it looks like it will be extremely helpful/ inspiring.

    Noted about keeping removed parts and SS screws.

    Cheers

  19. #54
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Rumars View Post
    Structural sheating does not need the frames, you are replacing all the transverse strenght and stiffness of the frames with material on the outside. While strenght is not a problem, but stiffness comes from thickness and you need a fairly thick sheating. That's why cold molding is cheaper, you can use fairly thick veneers 4-6mm that build thickness fast. The same thickness with fiberglass consumes a lot of epoxy and glass, it was usually done with polyester. You probably need 10-12mm of sheating for it to be structural. 1mm of glass is approx 1000g/sqm of fiberglass plus the same amount of resin. It is cheaper to convert to a cored construction by sheathing the inside also, that way you only need approx 1mm of fiberglass each side. A biax fabric is what I would use.

    Non structural sheating is two layers of thin (1,5-2,5mm) veneer or/plus 2-300gr/sqm of fiberglass, a woven fabric usually, and is there only for waterproofing, worms, and a little bit of abrasion protection. This requires sound frames to take the sailing loads, otherwise it will rip at the seams. Replacing framing you have two options, steam bent and laminated. Steam bent frames are quick to do, maybe 3 full working days for a team of two people to replace and refasten the whole boat. But you need green wood for steaming, pay for the copper nails and a second person at least for the riveting. Laminating can be done multiple ways, the quickest is to laminate in place glueing and stapling the first veneer to the planking. Cleanup can be a little scary, you need to grind the frame sides in place. Fasteners to the planking are optional.

    Prep time for all methods is equal, the hull needs to be sanded clean inside out, all rotten wood replaced, all splines and gaps glued solid. Temporary bracing is just some strips of ply and transverse wood, this is an already splined boat, it will not loose shape easily.
    What you end up doing is mostly a matter of preference, how you want to work and what result pleases you more esthetically. Local materials availability can also play a role, cold molding structurally is easier when having access to commercial sawn veneers.
    I'm heading down the path of replacing the framing, I'm pretty keen to learn more about that stuff and give it a go.

    Thanks for the advice!

  20. #55
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    Yesterday I was lucky enough to have my friend's father, who is a shipwright, have a look over her and recommend how I proceed. He has built wooden boats his whole life, mainly fishing trawlers, but he now also restores wooden boats like mine. He showed me his own carvel built boat that has been restored and epoxy/ cloth coated which has been living on a trailer for the last 15 years with no problems. He has another similar carvel boat restored in the same way that also has had no problems. Inspirational stuff!

    He basically suggested what has already been said by larks and others already on this thread.

    Process roughly as follows (not particularly in order):

    Replace timbers running down to keel with solid floors as Nick suggested earlier.

    Steam in new ribs - I've sourced a local mill that can supply green spotted gum and the shipwright leant me his welded steel post to boil / steam them in. He said don't bother with a steam box.

    Replace the innermost gunwale section, again using green spotted gum- he said it probably won't even need steaming, but if it does, it will fit inside the steel post.

    Refasten using 316 SS screws. Probably 8 gauge.

    Use thickened epoxy to seal the gaps in the planking or where the splines have fallen out. Maybe replace splines, I'll decide when I’m closer.

    Also use thickened epoxy to repair the stern post/ keel.

    Add some additional ‘half floors’ secured to the centreboard case and planks to add additional strength for trailering.

    In addition, I also want to add another stringer about in line with the top of the centreboard case to fasten thwarts to. I haven’t thought this over much but I’ll do more research when I get closer.

    Sheathe the outside of the hull with epoxy and 2 oz (I think 600 GSM metric) chopped strand mat. Trowel thickened epoxy into the surface to fill the bumps.

    Coat the inside of the hull with epoxy (including under where the ribs will fasten to the planks, done as they are replaced).

    I’ll post photos as I go for future reference.


    Thanks all!

    That sounds like a really good plan Ruey and you’re very fortunate to have a mates dad with that kind of experience. I’d suggest stick with that now and don’t be distracted by any more alternatives or you’ll end up winding yourself up in knots.
    Larks

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    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  21. #56
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Ruey, I’d add that I suggest replace or add splines wherever you can: wet both the splines and the seams out with unthickened epoxy and then glue them in with thickened epoxy rather than filling the seams completely with thickened epoxy. Likewise with your stern post and keel - splice in a dutchman rather than just filling holes or any other missing timber with thickened epoxy.

    'Talking from experience as I’m currently doing some splining and hull repairs myself, you would be amazed at how much epoxy it would take to completely fill your seams and the splines and Dutchemn are a much cheaper and ultimately easier option to fill those voids, plus they’ll help to push the epoxy all the way through the seams. You’ll find it difficult to keep a heavy gob of thickened epoxy in place without some sort of mould as it will just want to sag and run.
    Larks

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  22. #57
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    What do you think about just filling the gaps in the planking with thickened epoxy, and also fixing the stern post / keel where its a bit loose with the same?
    Quote Originally Posted by Larks View Post
    Ruey, I’d add that I suggest replace or add splines wherever you can: wet both the splines and the seams out with unthickened epoxy and then glue them in with thickened epoxy rather than filling the seams completely with thickened epoxy. Likewise with your stern post and keel - splice in a dutchman rather than just filling holes or any other missing timber with thickened epoxy.

    'Talking from experience as I’m currently doing some splining and hull repairs myself, you would be amazed at how much epoxy it would take to completely fill your seams and the splines and Dutchmen are a much cheaper and ultimately easier option to fill those voids, plus they’ll help to push the epoxy all the way through the seams. You’ll find it difficult to keep a heavy gob of thickened epoxy in place without some sort of mould as it will just want to sag and run.
    Larks got there first.
    Getting epoxy to penetrate into thin grooves is tricky, and takes a lot of material. Plus a lot of waste.

    The stern post bolts, timber may have decayed, but I'd think it'd be a bigger mess if it had.
    There's also the chance the bolts have worked their way out over time, do they have a nut on the inside? Or are they drifted in? Either way - pull them, carve in a dutchman, glued in place with epoxy. And replace/reuse the fasteners . Don't rely on a sheath of glass alone for that spot.
    It's all fun and games until Darth Vader comes.

  23. #58
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Using a lot of epoxy is not wasting it.
    Using the minimum is when it is wasteed.
    How those old batten seams holding up ?

  24. #59
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Fair point about the batten seams
    But are you confident that in similar circumstances epoxied seams wouldn't look similarly disheveled?

    My comment on waste was simply that mixing the epoxy and slopping into the crevices creates waste. You don't get 100% in there. So, as well as the filling requiring lots of material ($$$'s), inevitably, there is also waste.
    Splining, or edge glued battens, sheathed over, is an economical way of getting the same result. Ask any strip built boat owner.....
    It's all fun and games until Darth Vader comes.

  25. #60
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    "The Putty knife is mightier than the caulking iron" is a saying I never put on a tee shirt or a hat.But I always said I would.
    If yer "slopping " epoxy around so that much of it is not going where it belongs , or gets there and then sags out...that's a problem with how one uses epoxy, not the epoxy itself.

  26. #61
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Bruce, will epoxy stay in a seam that is above your head (i.e. in a horizontal plane, so no timber below it), if you thicken it enough? I'm wondering how hard it would be to get it to stay in the bottom of a hull, as opposed to the sides.

    In this case he can invert the hull, so I agree that just pushing epoxy in there (may have to tape the inside of the seams to reduce waste) would work.
    http://fairmaid.blogspot.com.au/

    "It's dawning on me that I should have worked out the tumbler details more in advance, rather than rely on bluster and over confidence. But that's just silly." Jim Ledger.

  27. #62
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Not hard at all Aquinian, just use more powder.

  28. #63
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Paul Johnson, my epoxy mentor, constantly urged me to be aware of the hydraulic pressure of the epoxy and puttyknife. Keep pumping.
    He was a bit nutty about it actually, only allowing one inch knives .He believed wider knives would lead to shortcutting , not reaching everywhere.
    Different thickeners are better than others as well, most of us know there is a huge difference between 403 and 407 , fer instance.
    (please stop using floor sweepings on yer boats).
    And the epoxy does not have to go in at one shot, most know this as well.
    If you think splines are needed,go ahead, but don't say they are better or cheaper of faster...they are just more accepted because they look cleaner.imo.
    The job that was done on this boat exhibits minimum use of epoxy,resin staration everywhere.

  29. #64
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by gypsie View Post
    Fair point about the batten seams
    But are you confident that in similar circumstances epoxied seams wouldn't look similarly disheveled?

    My comment on waste was simply that mixing the epoxy and slopping into the crevices creates waste. You don't get 100% in there. So, as well as the filling requiring lots of material ($$$'s), inevitably, there is also waste.
    Splining, or edge glued battens, sheathed over, is an economical way of getting the same result. Ask any strip built boat owner.....
    No bolt on the inside, just bronze rod I guess.

    Ok will do, cheers!

  30. #65
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Ok about the splines/ glued seams I might try both ways and see which way works better for me.

    I found some Oregon (Douglas fir) timber, 100 x 75 x 6000mm, at a second hand building store and bought two lengths to make a mast / spars out of later. I also have an old oregon surf boat oar that is about 75 x 6000mm that I was thinking of using.

    The two lengths that I did buy, unfortunately, have holes for bolts drilled through them every two meters or so. I can’t actually remember as I haven't picked them up yet but I think the holes are about 10-15 mm wide and are recessed with a hole saw. Will this make them not such a good choice for masts / spars or can I just fill the holes? There might actually be some lengths without holes now that I think about it and I might be able to swap them. The shop was closing when I was there and stupidly bought those two lengths with holes in a hurry.

    Also the innermost section of the gunwale (inwale?) that needs replacing on both sides is also Oregon (Douglas fir). Maybe if the lengths that I bought aren't suitable for spars, and I can’t swap them, I could just use them here and in other parts of the boat? The reason I’m asking is because I thought that a hardwood may have been better suited for this application.

    I’ve pulled out the first pair of ribs (remembering to only take out every second pair at a time) and removed the fastenings from the planks. I will proceed to take the planks back to bare timber then epoxy where the rib will fasten over. I will obviously also remove the metal straps now, as I plan to epoxy coat the inside?

    I was luckily given a full set of pre-cut and bevelled spotted gum ribs that were going to be used for a repair that never got done. They are almost the same size and should work. Just waiting for a new belt for the band saw to arrive then I can begin making the floors and steaming / bending in the new ribs!

    Last edited by Ruey; 10-26-2020 at 09:03 PM.

  31. #66
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Also,

    What about epoxy coating the inside? The paint comes off really easily, but the tar underneath is very hard to completely remove. It might be a huge job to prep it for epoxy.

    If I don't coat the inside, will I have to be very careful to not let water come into the hull, even for shot periods of time?

    Thanks

  32. #67
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    Also,

    What about epoxy coating the inside? The paint comes off really easily, but the tar underneath is very hard to completely remove. It might be a huge job to prep it for epoxy.

    If I don't coat the inside, will I have to be very careful to not let water come into the hull, even for shot periods of time?

    Thanks
    You won’t be able to stop it getting wet inside and whatever you paint it with will give you protection for general use - you'll just need to make sure you get a good adhesion for whatever paint you use and that rain water doesn’t sit in it when she’s not in use.

    You could look into sealing the inside with Everdure before painting or epoxying the inside of the hull. Clean it down with thinners and apply the Everdure straight away.

    It’s a penetrating epoxy and I confess that, although I have used it, I’m no expert on how effective it is and there seems to be some debate in that regard. I’ve been talking to the AkzoNobel guys over the last couple of days about paint systems for my Huon Pine H28 topsides and, as I’ll be taking it back to bare wood, that’s what they have recommended (Everdure under the paint system) so I intend to go with their recommendation.

    Because Huon pine is an oily timber, even when aged, I’ve always wiped it down with thinners anyway before gluing or painting it to remove enough of the oil to allow a good bond before oil moves back to the surface and the AkzoNobel guys suggest that the additional step of coating with Everdure will improve that adhesion even more. There is an additional cost involved of course.

    Having said all that -once you get the surface prepped well enough to paint then you’ll have it at in a condition that will still allow you to epoxy coat it anyway.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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    "Keep away from people who try to belittle your ambitions. Small people always do that, but the really great make you feel that you, too, can become great!"

  33. #68
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Ruey View Post
    The two lengths that I did buy, unfortunately, have holes for bolts drilled through them every two meters or so. I can’t actually remember as I haven't picked them up yet but I think the holes are about 10-15 mm wide and are recessed with a hole saw. Will this make them not such a good choice for masts / spars or can I just fill the holes? There might actually be some lengths without holes now that I think about it and I might be able to swap them. The shop was closing when I was there and stupidly bought those two lengths with holes in a hurry.

    Also the innermost section of the gunwale (inwale?) that needs replacing on both sides is also Oregon (Douglas fir). Maybe if the lengths that I bought aren't suitable for spars, and I can’t swap them, I could just use them here and in other parts of the boat? The reason I’m asking is because I thought that a hardwood may have been better suited for this application.



    Hard to judge on the oregon based on what you’re saying as to how well you can rip it down for spars and it also depends on how you intend to make the spars - are you thinking of making them as birdsmouth spars?

    Some small holes can cut out and dutchman repaired with like timber but filling the holes with epoxy or something won’t work. It sounds more like you may get a number of short lengths either side of the holes but you could scarf pieces together for the length that you need, just make sure that the joins are well staggered in the finished spar.

    If the inwales are Oregon and you’re replacing a short piece of it you’d be better to stick with the same timber. If you’re replacing the whole thing you could happily replace it like for like but if quantity is an issue and you have access to something more durable that will take the shape there’s no reason why you can’t use something else. Some Oz hardwoods don’t steam bend too well so you’ll need to experiment to see what you can do with what you have or consider ripping lengths down to a thinner more malleable size and laminating them in place.

    You’ll find plenty of use for the orgegon either way, you’ll be able to use offcuts for any additional framing such as seat and locker frames, deck beams etc.
    Last edited by Larks; 10-27-2020 at 12:16 AM.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  34. #69
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    I would just paint the inside with good quality single pack marine paint, especially if you are dealing with tar.

  35. #70
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    Default Re: Rebuilding a Carvel Hull - Please Help!

    Quote Originally Posted by Larks View Post
    You won’t be able to stop it getting wet inside and whatever you paint it with will give you protection for general use - you'll just need to make sure you get a good adhesion for whatever paint you use and that rain water doesn’t sit in it when she’s not in use.

    You could look into sealing the inside with Everdure before painting or epoxying the inside of the hull. Clean it down with thinners and apply the Everdure straight away.

    It’s a penetrating epoxy and I confess that, although I have used it, I’m no expert on how effective it is and there seems to be some debate in that regard. I’ve been talking to the AkzoNobel guys over the last couple of days about paint systems for my Huon Pine H28 topsides and, as I’ll be taking it back to bare wood, that’s what they have recommended (Everdure under the paint system) so I intend to go with their recommendation.

    Because Huon pine is an oily timber, even when aged, I’ve always wiped it down with thinners anyway before gluing or painting it to remove enough of the oil to allow a good bond before oil moves back to the surface and the AkzoNobel guys suggest that the additional step of coating with Everdure will improve that adhesion even more. There is an additional cost involved of course.

    Having said all that -once you get the surface prepped well enough to paint then you’ll have it at in a condition that will still allow you to epoxy coat it anyway.
    I guess you're right, I'll need to take it back to bare wood either way. Everdure does sound good, I'll assess the additional cost when I get closer.

    Thanks for the tip! I'll defiantly use thinners on the Huon.

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