Page 4 of 27 FirstFirst ... 34514 ... LastLast
Results 106 to 140 of 937

Thread: Re-building my Ketch Tonga (1960)

  1. #106
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Do you happen to know of a website where I could mailorder it in Europe? Don't know what I'm doing wrong, but I've been more than an hour on internet now and the only sites that come up in my computer are in the US which not only means they charge a fortune for shipping, customs in Portugal will need ages to decide if they want or not want to have it in the country, I will have to pay an extra fee to get it out of customs and pay the import-tax and VAT of course.

  2. #107
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    46,985

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Dody View Post
    Do you happen to know of a website where I could mailorder it in Europe? Don't know what I'm doing wrong, but I've been more than an hour on internet now and the only sites that come up in my computer are in the US which not only means they charge a fortune for shipping, customs in Portugal will need ages to decide if they want or not want to have it in the country, I will have to pay an extra fee to get it out of customs and pay the import-tax and VAT of course.
    http://www.ebay.co.uk/itm/Borax-Sodi...-/321145555408

    https://mistralni.co.uk/products/bor...te-decahydrate

    https://www.greenshop.co.uk/search/r...2nm6esik0kp103
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  3. #108
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Thank you heaps!!! I just wanted to go through the order-process when this turned up:

    Please Note: This product has been reclassified by the ECHA as Reprotoxic Category 2 and as such is not available to the general public. Borax can only be purchased by Professionals and by trade and business users or for scientific research.

    I can't give any proof of being a professional - and we all know I'm not - so, I guess I'll stick with what I've got for the moment and see if I can find it locally in a shop somewhere around here.

  4. #109
    Join Date
    Jul 2011
    Location
    Lindstrom, MN
    Posts
    2,865

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Dody View Post
    Thanks for all the information. I've now been reading both, the Xylophene and the Tim-Bor saftety-sheets and have the feeling that there is not that much of a difference between them. Tim-Bor powder can turn into explosives when it comes into contact with certain chemicals or gasses.
    Borax is not flammable or explosive. Borax is used to fireproof materials, including wood.

    The chemicals that create hydrogen gas when mixed with borax are metal hydrides and alkali metals like sodium. They can burst into flame on contact with water or any thing that contains water. There is enough water in almost anything, including Xylophene to react violently with some metal hydrides.
    Management is the art of counting beans. Leadership is the art of making every being count. --Joe Finch

  5. #110
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    46,985

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Dody View Post
    Thank you heaps!!! I just wanted to go through the order-process when this turned up:

    Please Note: This product has been reclassified by the ECHA as Reprotoxic Category 2 and as such is not available to the general public. Borax can only be purchased by Professionals and by trade and business users or for scientific research.

    I can't give any proof of being a professional - and we all know I'm not - so, I guess I'll stick with what I've got for the moment and see if I can find it locally in a shop somewhere around here.
    Is your tame shipwright not a professional? Can you not buy it through his business?
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  6. #111
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Got that sorted with Professional only to find out they deliver to UK Mainland and Ireland only ... same elsewhere. More internet recherche, and, how stupid can one be? I came across this:

    http://www.restaurarconservar.com/Borax-Decahydrate

    there comes no description with it, it's under "cleaning" (which might just be a way around legislation), and the company is located in Portugal. Just to make sure, would

    Borax Decahydrate

    be the same stuff?

    Edit: on Ebay I found "Borax Sodium Tetraborate Decahydrate 99.9% Pure Lab Grade" 230 gr for 11.23 Euro, comes from Bulgaria
    Last edited by Dody; 07-26-2017 at 02:49 PM.

  7. #112
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    46,985

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Yes I think so.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  8. #113
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Yes it is the right thing. Highly toxic in the EU since 2010, before that it was considered safe to eat. Has a lot of uses, cleaning included. Mighty useful against cockroaches, ants, fungi, etc.

  9. #114
    Join Date
    Jul 2011
    Location
    Lindstrom, MN
    Posts
    2,865

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Dody View Post
    Got that sorted with Professional only to find out they deliver to UK Mainland and Ireland only ... same elsewhere. More internet recherche, and, how stupid can one be? I came across this:

    http://www.restaurarconservar.com/Borax-Decahydrate

    there comes no description with it, it's under "cleaning" (which might just be a way around legislation), and the company is located in Portugal. Just to make sure, would

    Borax Decahydrate

    be the same stuff?

    Edit: on Ebay I found "Borax Sodium Tetraborate Decahydrate 99.9% Pure Lab Grade" 230 gr for 11.23 Euro, comes from Bulgaria
    Yes for practical purposes and no if you are technically accurate. There are several borates that are used for fungicides and insecticides, and borax is one of them. Tim-Bor has another borate. The flame retardants that I mentioned earlier have some zinc chloride in them. Borax for wood preservation has been used for a long time. (from 1877)

    As for the hazards of Xylophene, I wasn't arguing against it, but felt that I should warn anyone reading this that it is flammable. As long as you are aware of the fire hazard and take the appropriate precautions. I searched the CAS number and found this: https://www.cdc.gov/niosh/ipcsneng/neng1380.html The explosion hazard seems to be at temperatures above 40°C, so it is more like diesel than petrol. I think... google google google Diesel fuel flash points 52°C (126°F). OK, somewhere in between, like jet fuel or kerosene.

    Wikipedia: (Borates) A number of closely related minerals or chemical compounds that differ in their crystal water content are referred to as borax, but the word is usually used to refer to the decahydrate. Commercially sold borax is partially dehydrated.
    Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered borax is white, consisting of soft colorless crystals that dissolve easily in water. A number of closely related minerals or chemical compounds that differ in their crystal water content are referred to as borax, but the word is usually used to refer to the decahydrate. Commercially sold borax is partially dehydrated.
    Borax is a component of many detergents, cosmetics, and enamel glazes. It is used to make buffer solutions in biochemistry, as a fire retardant, as an anti-fungal compound, in the manufacture of fiberglass, as a flux in metallurgy, neutron-capture shields for radioactive sources, a texturing agent in cooking, as a precursor for other boron compounds, and along with its inverse, boric acid, is useful as an insecticide.
    Management is the art of counting beans. Leadership is the art of making every being count. --Joe Finch

  10. #115
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    This is brilliant Dave, thanks! And by the way, my Xylophene found a different storage-place.

  11. #116
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Yesterday I kind of finished the "Boatbuilding Manual, Fifth Edition" by Robert M. Steward, revised by Carl Cramer.

    Just in case there should be others around trying to re-build their boats with the same very vague understanding which I have, of how they are actually assembled in the first place, it might be helpful if I tell what the outcome of reading this one was for me:

    What I very much liked about this book was the information about the different planking-systems, it has given me quite an interesting general overview. I could have skipped the lofting-section as I clearly don't need it, but it helped me to understand this subject a bit better. It also helped me quite a bit with the vocabulary and the names of certain pieces. For someone who's never worked with long or larger pieces of wood there is some helpful advice but, by reading this book, I was already more than 3 years into my project and had developed my own and different techniques, which do work pretty good for me. Saying this there were some new ideas which I will try to integrate in my way of working. Let's see how it goes!

    What I, from my point of interest in re-building my boat, found a little irritating: whenever the subject got really interesting for me to find out how this might have been done/assembled on my boat, so that I am able to work out a plan how to proceed, the reader gets the advice to look at his plans or get in contact with his designer. It might be a completely different thing for those who have got the plans and the designer is still alive and can be contacted. In my case there is no such thing. I'm not talking about dimensions, I'm talking about different ways of assembly. Also, from the experience with my boat during the past 20 years, I was surprised that there was only a few words mentioned that edges of plywood or the end-grain should be painted, but he didn't mention the significance it really has for the long-term survival of the boat one puts all his available energy in to build. Also, there was no mentioning of avoiding a tight fit - for example - between the deckbeams and the planking to allow air-circulation and prevent rot (depending of the way of building of course!). Now please, don't get me wrong! For someone using this book to build from the plans that just arrived, I'm sure it is a huge help, and this book is written exactly for these people.

    The sections of the book about "Plumbing", "Electrics", "Spars" etc. are for general information only, and he is right to do so. There are some really good books around, Nigel Calder "Boatowner's Electrical and Mechanical Manual" for example, "The Riggers Apprentice", "Sailmaker's Apprentice" "Understanding Sails and Rigging" just to give some examples. There is some more but I've got to look up the titles in my workshop - just in case someone has an interest, please let me know!

    I'll be with Howard I. Chapelle "Boatbuilding" for a while now and hope to get closer to some of the answers for all the questionmarks I've still got in my head! This is, for a few hours in the evenings I mean ...
    Last edited by Dody; 07-27-2017 at 06:30 PM.

  12. #117
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    It's quite difficult for me to explain what I mean with looking for answers. Maybe I best start like this:

    I took Tonga out on the hard in summer 2010 (the actual re-build was started end of 2013). One of the major problems I also wanted to address in the process was the lower support for the rudderstock next to the keel and, I had asked them to put me on extra-high wooden blocks to be able to inspect my keel properly. What I found was some rust under the keel and water dripping out.






    I asked the local welder for the fishing-boats, and he came up with the solution of welding a steel-plate under the keel. Knowing now what I didn't know then, I am still very angry with me about it, and it will be a big big stuggle later when I'm gonna drop the keel, but more about this when things are - hopefully - accessible from the side or the top.

    ZéManel, the welder, added an 8 mm mild steel plate under the keel, 3 beads of welding each along the side. Over the whole length of the keel. 8 mm is 250 KG extra at the lowest point of the keel, something I welcomed very much as with the longer masts she inicially heels a tiny bit more till she finds her stable position and this weight would get her back to how it was before.



    End of part I

  13. #118
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga


    I didn't address any of what was needed in this area for a while, but instead went on with the replacement of my deck and other things.

    Winter 2016 came and I managed to have a lot more space in my workshop. This was the right moment to get my engine out and stored in the workshop before something else finds it's way in this nice space. I wanted the engine out for 2 reasons: my engine beds need replacing and I want her to be completely overhauled. This especially, as I don't know how many hours are on the clock. Mercedes told me ages ago she needs a complete overhaul every 12.000 hours. On the clock I had 7.890 hours, but I fixed the electrical connection some time ago and don't know for how long it was not working. Also, when sailing in the Azores I dug out an old chart I wanted to use and on one of the courselines coming from the North there was a mark "engine-hour-counter to zero". This could have been from another engine, or it could have been that he didn't replace the counter when this engine was installed.

    The thing is, the space between propeller and rudder was too small to get the propeller off, and I can't pull the shaft with the rudder in place - both had to come out in my installation to get the engine out. I, and friends of mine, tried everything to get the shoe off, the one where the ruddershaft is connected to the keel, but nothing worked. As all this has to be re-built anyway the grinder came out and we cut it off



    But this was not the end of the story. After trying to dismantle what was on top, using heat and whatnot, the ruddershaft still wouldn't come out. The old system looked like this (haven't got a better photo):



    You can't see this in the photo of course, but the "ruddertube" stops below the waterline, something I don't want to keep like this. Instead of wasting more time on something that is no use later anyway, the grinder came out again and the rudder was cut off just below the stern.

    Here is the top-assembly of the rudderstock after it was finally out:



    and for those who are still not too scared to have another look, this is the u-profile where the ruddertube - or what was left of it - was originally welded to (the pipe in the front was plugged, probably the version of an earlier rudderstock), the little piece was the ruddertube:



    End of part II, part III to follow
    Last edited by Dody; 11-06-2017 at 11:57 AM.

  14. #119
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Of course, my engine came out in the end



    There is no point in re-inventing the wheel but ... in theory I knew what I wanted, but how to get there? I must admit I was struggling quite a bit. I wanted my new rudderstock to have 50 mm diameter (the old one was 45 mm). If I didn't want to get into trouble later, the rudderstock should have a clearance of 3 mm on each side inside the ruddertube - provided it's held in place with bearings. The new ruddertube I wanted to end 15 cm above the waterline, with a stuffing-box on top and a bronze-bearing at the bottom. The outside-diameter of the new ruddertube wouldn't permit using the same size u-profile. I managed to get hold of 1.50 m u-profile in 140 mm width which would fit nicely. With the help of an old scaffolding-pole, a builder's lead and a digital angle-meter, together with a stick I inserted into the cutlass-bearing to get my desired distance to the propeller I was able to get the correct angle and position I wanted the ruddertube (and the rudderstock) to have (it also has to go through the deck so I can attach a tiller for the windsteering). With the correct angle and some plywood to simulate the thickness of the hull when the ruddertube is in - to get her length right - slowly the blockage in my head disappeard.

    I guess you will all laugh about me, but as I never worked with things like this I wanted to do it step by step. So, first the ruddertube and an oval hole in the u-profile for it to fit in. I made a drawing which is not to scale, but lucky enough Lourenço in Alcobaça had no problem at all to understand it:



    It all took a while, finally it was ready and exactly as I wanted, you can't believe how happy I was about this working so well! I also had asked him to make a spare bearing and a puller for me. Here it is:






    Leandro, my ex neighbour from the fishermen's workshops here, welded the new u-profile in. Now I had to find out, where the flanges will have to go. I was hoping I could do the rudderstock in 2 pieces. The old scaffolding-pole came out again, I inserted the ruddertube into the hole and held it in place with my little crane from the top and wooden blocks where the scaffolding-pole could rest on the bottom.
    There was heaps of measuring going on, but no chance. It's got to be in 3 pieces, otherwhise I will always need a crane or dig a big hole when I've got to replace the bearing - or if I have to pull the shaft and don't manage to find a good solution when building my new rudder.




    End of part III, to be continued
    Last edited by Dody; 11-06-2017 at 12:24 PM.

  15. #120
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Again the simulated hull thickness etc. came into play











    Of course I was scared I would overlook something. I went to the beach and the river to have a good thinking-session, and it was fun big time to make some sketches with low tide and actually found something I had overlooked!



    End of part IV, to be continued
    Last edited by Dody; 11-06-2017 at 12:28 PM.

  16. #121
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    What I had overlooked was some way of blocking the whole rudderstock on top from jumping out of it's fitting below.

    First priority now was to make sure the lower forward end (the shortish one so to speak) of the ruddertube will still stick out of the hull when I've reached the planned hull-thickness. When I had it all aligned as good as possible for the moment, I could mark out where it has to be welded to the u-profile.

    To be able to take the 2 lower flanges apart, I need a clearance of 15 mm - meaning the distance from the top of the flange to the ruddertube. Also, the rudderstock has to sit in a fitting on the bottom over which it has to be lifted, the size of this needs to be added to the clearance. Hm, how high am I gonna make it?

    I walked across the yard and had a good look at the rudder-systems of the fishing-boats which were out of the water for maintenance. No matter what the size of the boat, the majority had a 5 cm long tube taking the rudderstock below. What is right for them can't be too wrong for me I decided, so 5 cm it's gonna be!

    This gave me the approximate length of the lower rudderstock-piece. As I have neither the fitting nor worked out how this all will be later, I left that part a bit longer.

    The next rudderstock-piece, the one that goes inside the boat, is limited by the distance from bottom-end of the ruddertube to the ground, preferably a tiny bit shorter (so I'm able to get it out without a crane or digging a huge hole). Inside I wanted it to end somewhere with enough clearance on top for the little tiller-arm of the hydraulic steering to be able to turn properly and also a good place to install the hydraulic ram for my steering. In theory this wouldn't be that much of a problem as my little deckhouse aft will be replaced anyway, and I can build it which ever way I want, but I would actually like to keep it very similar to it's original in appearance. This gave me the best length for the second part of the rudderstock.

    Whatever was left would be the top-part, going through another bearing and a seal and coming out on top of the aftdeck. At the moment I think/hope it will just be enough. I had asked Lourenço to get me a piece of 316L in 50 mm, 3 m long and perfectly straight and true to size. It took him through a lot of trouble, but in the end he found a supplier who would give a guarantee for it.

    There was still something I was breaking my head about: the rudderstock-pieces coming from the top and the bottom have to be tightened together in a reliable way. At the same time I've got to be able to take them apart and through the bearings without stuff sticking out.

    One day, I was just carrying my propeller to the workshop, my eyes fell on the cone of it. Hang on, why not, this could be the solution! I immediately dropped everything, drove over to Lourenço and asked him if this would work and if it is possible for him to make something like it? Sure he can, and we got really excited!

    He's got heaps of work, so one needs to be patient. It was important for me to have the ruddertube welded in place so we could get on with the planking, and I wanted to use the proper rudderstock to be able to align the whole system perfectly. One day the flanges were all ready, still missing was the little tiller-arm and the "castello"-nuts. I borrowed it all, aligned it perfectly together with Leandro, and he welded it in place. I was really scared that we might cause distortion in the ruddertube with the welding, but Leandro was super-careful and everything went great without distortion.

    Will send some pics in a bit, my internet keeps dropping at the moment and I had to write this twice already!
    Last edited by Dody; 07-29-2017 at 03:17 PM.

  17. #122
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga









    Lourenço:



    and Leandro:

    Last edited by Dody; 11-06-2017 at 12:37 PM.

  18. #123
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Peerie Maa View Post
    Pull a couple of the galvo nails to see if they have started to corrode, then seek advice on what you find. If the plank is dry and the galvo looks OK, you shold be OK with monel.
    The thick fat nails recommended by the books are I assume for conventional caulked carvel, where the nails do the work that in your boat is shared by the glued plywood skin, so a lighter nail may well work.
    Hi Nick, with going through all my pictures I actually found out I made pictures of some of the nails we pulled from the stern-area. These nails come from above the waterline, there might be a completely different result with the ones below the waterline which I will only find out once I get there:

    Last edited by Dody; 07-29-2017 at 03:02 PM.

  19. #124
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    46,985

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Dody View Post
    Hi Nick, with going through all my pictures I actually found out I made pictures of some of the nails we pulled from the stern-area. These nails come from above the waterline, there might be a completely different result with the ones below the waterline which I will only find out once I get there:

    It looks as though you have caught those just on the turn.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  20. #125
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    You might be wondering where I am with my project at the moment? These pictures are from today:







    I've been playing today with something I wanted to do for a long time: assemble these 2 supports. Got 8 now, 4 in metal with a wooden block on top I'm using for keeping the wood I'm working with at the moment next to the boat and treating it, and 4 of this type for working with tools/machines. They look a bit fancy, but shops here change their stock from time to time and in this occasion I only had a choice between very cheap ones falling apart when you look at them, and these. They are actually not too bad because I can adjust the height and they are quite stable. Little Max joined in to help me, and of course we've now got some of the glue on our tail and the left hindleg. He inspected them thoroughly and thinks they are ok

    Last edited by Dody; 07-30-2017 at 04:58 PM.

  21. #126
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    The plan is, first to get these deckbeams and side-deckbeams aligned (none of my deckbeams were fair to each other so far) and get the knees sorted, because now it's easy to work on them. The top layer of the beamshelf has about 2 cm of rot somewhere in front of the chainplate, and it has cutouts where the steel-brackets (see pictures before) went through it. It's less trouble to replace it, than pulling all these nails I can't get to properly (sure, I could cut off the toerail which has to go anyways, but I wanted to do this at a different stage and it doesn't help with the gaps who are there).

    When all this is done, I would like to sort out the stringers properly up to the stern, install knees between the transom and the planks on both sides, lay the side-deck with plywood and plank the stern.

    There is something I'll write about this chainplate in a bit. It is my "semi-permanent" emergency chainplate I installed when the original broke, it worked pretty well but I'm looking for a different solution - but more about that later.

    Now. Planking the stern has to be completed before I lay the last part of the deck as I don't want to have any gaps or cause any trouble there, in my opinion the surface of the deck has to overlap however the stern is made. Not sure yet how I'm gonna do the planking properly. I guess it would be best to start from the bottom? Will send a photo tomorrow, maybe you can help me with advice?

    Well, that's my plans right now. What is your ideas, criticism, advice, suggestions? Am I overlooking something? Would be happy to hear your opinions!
    Last edited by Dody; 07-30-2017 at 06:35 PM.

  22. #127
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    The toerail needs to go before you plank the deck or the topsides. The ply on the deck needs to butt on the topside ply, then fiberglass over the joint, and then the toerail gets glued on. There may also be rot under the toerail.

  23. #128
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Butting ... sorry Rumars, my fault, should have explained that a bit better! The ply you see in the pictures has to go, as does the little cabinhouse which will be re-built some time later. I only left the ply in place temporarily to have something to stand on instead of balancing on the deckbeams risking to fall overboard.

  24. #129
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Yes I understand that. And you re now making structural repairs so the toerail is not a priority, plus it holds up your tent. But the toerail covers the hull-deck joint and that is the most likley place to find problems. If you want to adjust the deckbeams and replank the deck it has to go before you can do that. I would remove everything and hire 2 strong guys to longboard the top of the deckbeams after doing the structural bits and prior to planking the deck. And I would want the deck plywood covering the endgrain of the hull plywood, like a lid covering the edge of a pot. Then glass over the joint and only glue the toerail to the deck, no screws or any other fasteners into the plywood.

  25. #130
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Ah, I see what you mean and you are certainly right. This was something I inicially thought before I cut the deck open when I started with the job ages ago. What I found out then was (at that moment to my relief I admit), that the plywood of the deck stopped somewhere, maybe 2 cm inside the toerail. So, what I did was replacing it in exactly the same manner. I know now that it is very wrong. But honestly, I don't see myself ripping 12 m of completely new deck off and start all over again.

  26. #131
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    That is bad but not a disaster. You do not have to take the new deck off to resolve it. First you remove the toerail and anything under that down to the deckbeams. Then you are left with a gap from the edge of the new ply deck to the hull side. Clean up the edge with a router or plane (I suppose there is Sikaflex squeezout) so that you have a clean edge. Then a few centimeters inboard from this edge you router a rebate down to the first layer of deck ply, then another one further inboard down to the second layer (I think you said the deck is 3 layers, and you may have to do it in the reverse order because of the staples). Now you have created a stepped butt joint and you can plank the gap with fitting piecies of ply. First layer to first layer, second to second, and third to third. Because of the rebates the joints are not on the same plane and each layer reinforces the others. Glue with epoxy like you did the deck. Generous overlaps are in order. Alternatively you could do a scarf joint instead of the stepped butt joint.

    I think you need a plan for the work order because right now you are making it harder then it needs to be. Removing the toerail gives you easy access to the beamshelf, top stringer and frame ends. You can easily clean up everything, replace rotten parts and install the knees. Then plank the deck with an overhang, plank the sides and then cut the overhang with a router.

  27. #132
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    It looks like this:







    still possible to see a little bit of it, the fibreglass was going over the top of the wood (maybe 5 cm higher than the deck). The toerail consists of 3 parts, 1 each on the side upright, another piece going across.

  28. #133
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    And now I'm in trouble. I've just discovered a split frame.

    One side looks like this:



    the other like this:



    would it be possible to epoxy-filler-glue this or does it have to come out?

  29. #134
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Everything down to the painted bits needs to go, and prefferably never come back again. Ever.

    I really am serious with this. You rip out that batten on the inside with the old decknails out, and the one on the outside where you cut the fiberglass and everything that sits on top of it.
    For rebuilding you plank the outside up to the level of the beamshelf with a batten nailed into the beamshelf and into the stringer under it (looks like you replaced or sanded that one). One fastener from the outside into the beamshelf, the next from the top into the stringer. Then to cover it and build up the height to the level of the deckbeams, you cut a covering board out of ply and glue and nail or screw it down on top. Needs to be fastened into the beamshelf and the stringer so mark the previous fasteners positions ont outside. Use sika like you did on the deck. The ply deck you extend over this covering board and over the outside plywood planking that will go over the stringers.
    How did you plank the deck forward where it is already done? To where the deckbeams end or up under the toerail where that line of nails is in the second photo? Depending on how you did it we will see what the best way is to make the joint there.

    For the toerail (when that time comes) you glue wood blocks on the edge of the fiberglassed deck and then glue and screw a batten on top of them. It will look like a handrail. If you want a rubbing strake you glue it on the outside of the planking.

  30. #135
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    That frame is not so bad. I would extend the knee down the frame to the gusset. And when you refasten you could put some long screws into the frame to tighten her. Replacing is not that bad either, you take out the fasteners in the gussets, underdeck beams and diagonal support then pry the frame from the stringers.

  31. #136
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    What do you reckon could have caused it? The very first frame in the front has splits (is still on my list), and this one.

    Concerning my toerail I'm still brooding, there must be another solution.

  32. #137
    Join Date
    Nov 2014
    Location
    Seattle, WA
    Posts
    3,988

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    I've been lurking for a while. Dody - great project. I'm impressed! Regarding the toe rail... Rumars is right. And I don't think the work needed to deal with the deck section you have already done is that much effort. Certainly not in comparison to the rest of the project. I did something almost identical on a 50' Huckins a few years ago. You can probably just half-lap a section of plywood between the deck edge and the existing deck once you have extended the hull planking level with the deck beams. Do it now and it's done. Leave it and that area will definitely come back to haunt you later. All the water that hits the deck ends up at that joint and it *will* eventually get in and ruin the work you are doing now.
    - Chris

    Life is short. Go boating now!

  33. #138
    Join Date
    Dec 2016
    Location
    EU
    Posts
    578

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    No way to say exactly why the frame cracked without detailed autopsy. May be grain runout, fasteners corroding and expanding, a big load applied on the stanchion that was bolted to it, water coming in, collision, or any combination of the above. As I said replacing that frame section is not complicated.

    Regarding the toerail you do not have a choice. If you like it that much and want to preserve it you can cut it off at deck level and reglue it on the deck aferwards. But the pictures show rott and it will not be only at this end. If you want the same toerail you probably need to disassemble it in its component parts and replace everything rotten. But I would rather see a nice slim toerail with a lot of limber holes to shed water from the deck.
    I would cut it of where you did not put the new deck on. Then you can install the new deck sections the propper way. You can deal with the rest at a later time. But I bet that this construction is the major culprit for your old deck (and furniture) rotting away. It is basicly impossible to keep the joint between plywood edge and toerail watertight. Once water gets in it can not get out and the plywood rots from the inside. Then water travels down into the boat and you know what that does.

    How do you plan cold mold the plywood on the topsides with that thing in the way? You see that even in the old construction the fiberglass is going over the edge of the plywood and a batten protects the ply edge. Did you plan to glass over the existing toerail to the deck?

    I will be really harsh. If you do not get that thing of all the work you do now is wasted. In a few years all the problems will be back.

  34. #139
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    46,985

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Quote Originally Posted by Rumars View Post
    No way to say exactly why the frame cracked without detailed autopsy. May be grain runout, fasteners corroding and expanding, a big load applied on the stanchion that was bolted to it, water coming in, collision, or any combination of the above. As I said replacing that frame section is not complicated.
    Dody,
    Is the wood still hard where the component was bolted to it. If it is hard I think that they are just drying cracks. Some fastenings driven across the crack should fix it. However the cross member at its top has a rot pocket which is a bigger issue.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  35. #140
    Join Date
    Jun 2017
    Location
    Nazaré, Portugal
    Posts
    809

    Default Re: Wood - Plywood - Epoxy bond, re-building my ketch Tonga

    Hi Chris, thanks! I've been reading your "On the Subject of free Wooden Boats" and your really heartbreaking Perihelion-story. It takes a lot of courage to do what you did, but it seems the right decision. I've started reading about your Petrel now, also Jim's "the harbourmaster called me today" and am enjoying both very much. The only problem: I sometimes would like to ask questions or say something, but that doesn't work because what I'm reading was posted a long time ago - got to be patient with boatbuilding and reading about boatbuilding, and one day I will have reached the moment where it's okay to be there. Still, it's good fun and a wonderful thing to know that there are others around who are doing similar things with their boats, people who are alive and have feelings, some hickups and drawbacks here and there as it happens with me too, but with persistence and tenacity we will get there in the end, I am sure about it

    Although, I must admit, sometimes I get a little scare. There is a boat here on the other side of the yard. It took him 40 years to build her, the last 12 years fulltime, from around 8 in the morning till 4 o'clock at night, his marriage got destroyed and the relation to his son broke up. He had never sailed a boat before, and got a bit carried away with lots of things. About 3 years ago she finally went in the water for 9 days, then he got a scare and she had to be hauled out again for improvements. 6 months later she went back in the water. Together with friends he sailed her to Peniche (25 Miles down the coast). 3 months later I got a phonecall if I could come over to help him sail her back to Nazare. I did, 1 Mile out we were close to sinking and ending up on the rocks, the lifeboat came and towed us in, lucky I had my own VHF and stuff with me. She's now back on the yard here, and Pedro just walked away. There is still hope for change coz he came here last week with his new girlfriend and I tried to encourage them to sail up to Galicia, spend the summer at anchor in the Rias for a change, and just enjoy from the boat. Fingers crossed!!!

    With the toerail, it's not "only" a toerail but something that serves for a multitude of purposes on Tonga. Stanchions with proper 8 mm stainless-wire tightly streched are attached to it, it's part of the chainplates (there are quite some thinking-processes going on about that in my head and I haven't found the solution I'll be happy with yet), my aft and midships docking-cleats are attached to it, the adjustable pulleys for the sheets of my 3 foresails are attached to it (there is tons of force they have to take from time to time), the fairlead for the genoa- and jib-sheet sits on top of it to lead it to both winches, all this so my deck is free from all this stuff where you always bang your feet on and so on. Well, I took most of it off for the moment as it would be in my way with working.
    The plan was, definitely not to create the typical gap where rot can happily develop, I had my share of that. I was thinking more about a system with laminated wood getting to around 5 cm above the deck, bolted to the beamshelf and across from the planks/stringers, an Epoxy-fillet from the inside between deck and laminated wood, the 3 layers of diagonal plywood-strips laminated to it from the outside, and the whole thing encapsulated around on the outside by fibreglass with Epoxy. Hm, how to explain? Imagine fibreglass with Epoxy going around the outside of everything - deck, toerail, hull. To make it more pleasing to the eye and to have something proper to attach things to, I would like to add wood - similar to how it was done before - as kind of a u-profile-cap, screwed to the inner part with sealed screws and plugged (with Epoxy-resin, not as like before with glue that gives up some time later!!!) so water stays out. Yes, the water will run along the inside of the toerail, but with a proper fillet and fibreglass, the screws plugged with Epoxy-resin, the inner wood beveled on the underside, it should be possible to get that pretty foolproof as long as the varnish on the wood is kept in good nick and the screws stay where they are meant to be. And even if this wooden cap should develop rot somewhere, it wouldn't hurt as everything under it is encapsulated with fibreglass and Epoxy.

    Dunno, need some more time to think about it ...
    Last edited by Dody; 08-01-2017 at 05:14 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •