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Thread: How to restore this rot?

  1. #1
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    Default How to restore this rot?

    Greetings, all. New to this forum but not new to boating, been enjoying my 15' fibreglass outboard for the past couple of years. Always loved wood boats and am stoked to have landed this little but cute 7 footer. However it's not quite ready to hit the lake just yet, which is why I'm here seeking your advice.

    Picked up this custom-made beauty last week at a garage sale. Had been neglected as it sat outside where rain water and dirt sat on the floor where it meets the transom. Boat must've been left standing as in the first pic. Wood elsewhere is solid, despite the badly sun faded varnish.

    The underside appears to be fine, the thick marine paint coats are holding up nicely despite a few scratches. There are no holes despite the badly rotted areas seen in the pics, but that area is soft. If I was to push it, my hand would go through with medium effort, there must be a single layer of plywood still holding things intact. Due to this it is my hope that a fix can be achieved other than replacing the entire floor. Can this be done?

    I dread the thought of having to replace the floor, for two reasons: it'd be beyond my skill level, despite being handy with a table saw - and also due to lack of time. With 3 small kids, time is super tight. I know little about this sort of damage but was wondering if there's some way this structural damage can be reinforced other than replacing the entire floor. One thought - and I'm only speculating here - would be to apply some sort of wood filler to that entire area, or something of the sort. Then cover the area with a piece of plywood, possibly extending from the transom to a couple of feet towards the bow. Then of course seal things as best as possible. Is this feasible? Or am I relegated to replacing the entire floor? Or is there a better alternative?

    Please review these pics and let me know if there are additional pics you'd like to see. Appreciate any help you can give.

    https://tinyurl.com/yb52cdjy
    https://tinyurl.com/ya9kc6as
    https://tinyurl.com/ycchysg9
    https://tinyurl.com/y7ye5u24
    https://tinyurl.com/y82gszym
    https://tinyurl.com/ya9tlzzm

  2. #2
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    Default Re: How to restore this rot?

    i, and welcome to the forum.




    Prod the batten across the bottom of the transom and the end of the chine logs with an electricians screw driver to test if they are rotten.
    If they are OK you must take off the keel batten from the outside. Then cut out all of the rotten ply, with a cut straight across the bottom. Then either scarf in a new bit, or fit a new bit with an internal butt block and tape on the outside. Then re-tape the chines and transom bottom and refinish. Use epoxy glue and stainless or brass screws to secure the ply until the glue sets and epoxy resin for the tape.
    It really is quite difficult to build an ugly wooden boat.

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  3. #3
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    Default Re: How to restore this rot?

    What Nick said. Magic fix rot, plastic wood and snake oil won't do it. But it's a flat bit of wood, couldn't be much easier to repair.

  4. #4
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    Default Re: How to restore this rot?

    It's a relief to know the entire floor doesn't have to be replaced. Then again the thought of a circular saw slicing open the bottom is equally as terrifying.

    Checked all the surrounding supporting wood, no rot and seem fit.
    This afternoon I removed all the loose stuff, only leaving the single layer of the plywood. Seems that the damage is only in the first 6 to 7" but it does run from port side to starboard. Which is what I want to know: when you say to cut it, how far are we talking? This complicates things a great deal as I'd now need to apply whatever material (tape?) seen in the edges of the last pic in the links listed above. If this is the tape you're referring to, what is it called and how is it applied? What kind of materials would I need in order to complete the work? I also noticed that along the edges of the keel batten there is some sort of very hard glue or sealant, which is hard solid and kinda yellowish in colour. Is this the epoxy glue you mentioned in your reply? Suppose it would have to first be removed in order to take off the keel batten and then reapplied afterwards. This wouldn't be the same stuff as say, PL200? I ask cause I have several of these here and they come in a handy tube ideal for my caulking gun.

    These may seem like very basic questions but as mentioned earlier, I haven'd done this before and what may seem as clear as water to you, is all stuff I need to wrap my head around. All of a sudden working in my fiberglass boat seems a lot less daunting. Heh, after reading your reply I even looked for someone to do the job locally but found no one I'd feel comfortable with, as they all seem to specialize in too much stuff and none of it being wood.

  5. #5
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    Default Re: How to restore this rot?

    The yellow hard stuff is likely epoxy. The tape mentioned is fibreglass tape. You set the tape in epoxy to reinforce a joint. A butt join is two layers of wood, a backing piece if you will, spanning the join.

  6. #6
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    Default Re: How to restore this rot?

    Burn it
    Easier and quicker to build a new one (LOL)
    Last edited by Mark Bowdidge; 07-22-2017 at 05:39 AM.

  7. #7
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    Default Re: How to restore this rot?

    Yes, the hard stuff is probably epoxy glue, made by mixing epoxy resin with an appropriate filler. You are going to need to search up some instructions for using epoxy.
    To remove the keel batten take out all of the screws from the inside, and you may then have to cut through the glue line with a suitable saw.
    This is a butt block for a plywood bottom
    It really is quite difficult to build an ugly wooden boat.

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    Default Re: How to restore this rot?

    I would replace the entire bottom as rot spores have a nasty habit of traveling long distances in plywood cores. That bottom panel will not be all that hard to replace. It looks to have no rocker to it which means that no bending of the plywood bottom sheet will be needed. Once the old one is removed, the new one can be set in G/flex Epoxy on the chines and screwd down with short flat head bronze # 8 or #10 screws. I might add that twin stringers on the out side will protect the boat when sitting on the hard. They should be made of White Oak, Wych Elm or Locust. For even more protection glass the bottom prior to attachng the stringers. The bottom panel can be trimmed with a piloted straight router bit which will get you close enough to the chine to finish it with a plane and or random orbit sander.
    Jay
    Last edited by Jay Greer; 07-22-2017 at 11:52 AM.

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    Default Re: How to restore this rot?

    Appreciate all the expert advice. But there's one critical thing that I should mention that perhaps wasn't made clear: this is an untested boat, one that I don't even know will be a good fit for us (well, for me and possibly my little girl, as there's no way I'd put all 5 of us in it)

    With that in mind I am not ready to proceed to fixing it the right way, this is too big a job for someone that haven't done anything of the sort before. It is just too much time/effort/money to fix something that I may end up passing on to someone. At this point I just want to get the thing to float and hopefully try it out a few times. Hell, don't even mind bringing a small bucket along for the ride if some water sips in. Should it then prove to be something we'd like to keep in the family, I'd then be prepared to spend the effort fixing it the right way.

    With that in mind, would this temporary fix work: adding a few layers of fibreglass tape to the damaged area?
    Since it was mentioned that FB tape is used along the edges, it makes me wonder if I couldn't just add a foot or so of it along the stern area where the damage is. I mean, the shape is already there, so laying FB wouldn't be that hard a job. It may upset the purists that this 100% wooden beauty would be bastardized by having FB added to it, thus turning it into a hybrid frankenstein monster but if will give me an easy and quick way to at least try it out, then what's the harm? I simply have no time to devote to a proper floor replacement this year, but if I know the boat is a keeper, then next year I'd be better prepared to secure all the material and make the time to do it the right way.

    Does this sound like a reasonable way to go, at this time?

  10. #10
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    Default Re: How to restore this rot?

    In your situation I would make it float with as little effort as possible. Fibre glass and epoxy where needed or simply duct tape or some other quick fix. Test it and see if you like the boat (but don't trust it). If you like it, chop it up, burn it and build a new similar boat from scratch. My guess is that it will take less time to build a new boat than to fix the old one properly and it's more rewarding. As a pure amateur boat builder with limited equipment I expect that it would take me 50 - 100 hours to build a boat like that.

    The real danger is that you get hooked on boat building. My first project was similar in size to your's. Two boats and one kayak later I'm still planning the next (wooden) boat to build.

    Erik

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    Default Re: How to restore this rot?

    Quote Originally Posted by ERGR View Post
    In your situation I would make it float with as little effort as possible. Fibre glass and epoxy where needed or simply duct tape or some other quick fix. Test it and see if you like the boat (but don't trust it).
    You get it, this is exactly what my intention is, to first try it out to see if it's something that will suit us. Then go from there. As indicated above, there is no magic fix like using plastic wood (which was a thought I had but thanks to the replies here, now realize to be a useless idea). Heck, I could just slap a few layers of tuck tape to the area (the very sticky red stuff that never dries up) to keep the very tiny cracks from letting water in. But since Nick mentioned glass tape in his reply, it occurred to me that laying a few layers of FB to the area to be an easy and cheap way to go (material would cost me a mere $22). Sure, it will add drag at the part of the boat where you least want it, but at least it would let try it out. Seems safer than using tuck tape, plus, a lot less red-neckish.

    And as indicated earlier, I can always devote the time to fix it properly in the future, if this ends up being a good boat. As for building one, heh, no thanks. I'm afraid I could end up addicted to it, like that guy in Austria building those amazing 16' canoes. Who wants that kind of disease?

  12. #12
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    Default Re: How to restore this rot?

    Welcome!

    I don't do fiberglass anymore, but have see other folk speak highly of this book, and the cost is right (free!)
    The-Gougeon-Brothers-on-Boat-Construction (LINK)


    Good luck, and have fun!

    .
    .

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    ~~~ Henry David Thoreau

  13. #13
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    Default Re: How to restore this rot?

    Quote Originally Posted by Joolz View Post
    Appreciate all the expert advice. But there's one critical thing that I should mention that perhaps wasn't made clear: this is an untested boat, one that I don't even know will be a good fit for us (well, for me and possibly my little girl, as there's no way I'd put all 5 of us in it)

    With that in mind I am not ready to proceed to fixing it the right way, this is too big a job for someone that haven't done anything of the sort before. It is just too much time/effort/money to fix something that I may end up passing on to someone. At this point I just want to get the thing to float and hopefully try it out a few times. Hell, don't even mind bringing a small bucket along for the ride if some water sips in. Should it then prove to be something we'd like to keep in the family, I'd then be prepared to spend the effort fixing it the right way.

    With that in mind, would this temporary fix work: adding a few layers of fibreglass tape to the damaged area?
    Since it was mentioned that FB tape is used along the edges, it makes me wonder if I couldn't just add a foot or so of it along the stern area where the damage is. I mean, the shape is already there, so laying FB wouldn't be that hard a job. It may upset the purists that this 100% wooden beauty would be bastardized by having FB added to it, thus turning it into a hybrid frankenstein monster but if will give me an easy and quick way to at least try it out, then what's the harm? I simply have no time to devote to a proper floor replacement this year, but if I know the boat is a keeper, then next year I'd be better prepared to secure all the material and make the time to do it the right way.

    Does this sound like a reasonable way to go, at this time?
    It is not a beautiful boat, even when new it was just a cheap flatiron skiff.
    You could do a quick bodge with duck tape, but that will not add enough strength to make her safe.
    Do not take your kids out in it, because if that bottom fails it will come off the full width of the transom and you will be swimming.
    If you want to do a temporary fix with FRP, you will need to lay up about 1/4 inch thickness from at least 6 inch forward of the rot back to 6 inch up the transom and up the sides having first stripped off all of the paint and varnish to guarantee good adhesion to the wood.


    Of course, by the time that you have done that you could have cut off the bad bit, cleaned up the gluing surfaces and glued on a new bit.
    Last edited by Peerie Maa; 07-22-2017 at 04:42 PM.
    It really is quite difficult to build an ugly wooden boat.

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    Default Re: How to restore this rot?

    ^^^ what Nick said, plus I'll add that no one here is being a "purist". I'm not even sure what that would mean for that boat. It's a perfectly utilitarian little skiff that needs a relatively minor repair. Fixed up and with a coat of paint it would be a nice boat to row around your local lake with one passenger.

    In this case the right way to repair it is the way that will be safe for you to use it, especially if you want to take your daughter out in it. There is no goop or glue that will restore the strength to that joint. You could lay up FG to patch up the joint as Nick suggests but I think that's actually more work than just doing it right to begin with.

    My recommendation, for what it's worth, is to stop worrying too much about how much work you might put into this boat before deciding whether you like it. It's a weekend of work to fix the bottom "right". Maybe two at most plus another couple of days for paint. Then you would have a boat you could enjoy without worrying if the bottom would fall out. And once it's done you could easily sell it for $500 or so if you decide you don't want it any more. That's what I would do, but I like working on old boats. YMMV as they say.
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    Default Re: How to restore this rot?

    As others have said, the boat is hardly a classic. For a cheap fix I'd probably get some exterior ply and some goo in a tube. Just stick the ply on the outside going forward whatever, maybe 6-10 inches. You could even go aft past the transom a bit and pretend it's a bigger planing surface. You can use gorilla glue, a polyurethane sealant/adhesive, whatever. Bodge it up, have some fun, burn it at the end of summer. Maybe build a decent boat one day if you get some fun out of it.

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    Default Re: How to restore this rot?

    Quote Originally Posted by Phil Y View Post
    As others have said, the boat is hardly a classic. For a cheap fix I'd probably get some exterior ply and some goo in a tube. Just stick the ply on the outside going forward whatever, maybe 6-10 inches. You could even go aft past the transom a bit and pretend it's a bigger planing surface. You can use gorilla glue, a polyurethane sealant/adhesive, whatever. Bodge it up, have some fun, burn it at the end of summer. Maybe build a decent boat one day if you get some fun out of it.
    I don't think that would work well. The rot will have created a gap under the transom, so there is nothing there at that aft edge to pass the pressure load from the bottom patch up into the transom.
    It really is quite difficult to build an ugly wooden boat.

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    Default Re: How to restore this rot?

    Quote Originally Posted by Joolz View Post
    You get it, this is exactly what my intention is, to first try it out to see if it's something that will suit us. Then go from there. As indicated above, there is no magic fix like using plastic wood (which was a thought I had but thanks to the replies here, now realize to be a useless idea). Heck, I could just slap a few layers of tuck tape to the area (the very sticky red stuff that never dries up) to keep the very tiny cracks from letting water in. But since Nick mentioned glass tape in his reply, it occurred to me that laying a few layers of FB to the area to be an easy and cheap way to go (material would cost me a mere $22). Sure, it will add drag at the part of the boat where you least want it, but at least it would let try it out. Seems safer than using tuck tape, plus, a lot less red-neckish.

    And as indicated earlier, I can always devote the time to fix it properly in the future, if this ends up being a good boat. As for building one, heh, no thanks. I'm afraid I could end up addicted to it, like that guy in Austria building those amazing 16' canoes. Who wants that kind of disease?
    As you say it's only to try it out ... as long as you promise not to start with your little girl in the boat as well for the first try, I've got a very quick and unconventional method which doesn't make a big mess to clean up later in case you like the boat:

    Get yourself a thick plastic sheet, some of the stuff you can buy by the meter at a hardware store. With thick I mean thicker than plastic shopping bags. The sheet has to be big enough to cover the complete outside of the boat, over the top edges all around and a bit left to come inside to nail or screw it with some thin stuff to the ply on the inside so it does stay in place. If you manage to get clear plastic, people won't notice from the distance. Chuck it in the water and try it out. As long as the bottom aft hasn't desintegrated completely it will work.

    I've seen the same thing done by a guy who fell in love with a 24 m fishing boat which was badly leaking. He only wanted to take her from the North of France to the south of Spain for "repairs". Once in Spain, he used the fishing-boat as a male plug, welded a steel-boat with the same shape around her and cut all the wood out from the inside.
    Last edited by Dody; 07-23-2017 at 05:59 AM.

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    Default Re: How to restore this rot?

    Well folks, after getting over the nightmarish scenario of slicing open the bottom of the little boat with a circular saw, and taking another look at the boat, I realize now that this is what makes the most sense. As Nick said, it'd more work to FB the thing and still not having a proper fix. And as cstevens said, once the proper repairs are done, I can always sell it and recover my costs, if it came to that. So it just makes sense to do it the right way.
    Still concerned with removing the keel batten without breaking it, that epoxy is there good.

    Nick, please help me understand the steps:
    - I should remove the keel batten first.
    - remove the FB tape along the side edges and the transom's bottom
    - unscrew any screw holding the portion of the floor that's to be cut out.
    - use a circular saw and make a straight cut, about a foot in length (or further, depending on how far I can see rot)

    Once the above is done I suppose the next phase would be:
    - cut a matching piece of plywood to fit - please describe what kind should be used, or would any hardware store ones do, as long as it is the same thickness?
    - add a butt block as in the pic you posted above and instructions already given.
    - once that's hardened, fibreglass the joint on the outside of the boat. if this is correct, should I use mat? how many layers would you recommend? How far should the pieces of mat extend beyond the joint?
    - fibreglass the edges along the sides of the boat as well as under the transom. How many layers would you use?
    - apply a good coat of wood primer to all bare wood (and I suppose on the FB too?). Paint several coats of marine paint (or if this works, could I just spray automotive semi gloss white paint? Have several cans of these in the house)
    - once all the painting is done, reinstall keel batten
    - apply epoxy to edges of batten and all the interior joints

    Is this correct or am I missing any steps?
    And thanks for not giving up on me when I thought I could just short-cut my way through. Took me a couple of days to get over the fact that this is a bigger job than I had anticipated. I suspect this thing will be a keeper, so might as well do it right the first time. Really appreciate the expert advice.

  19. #19
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    Default Re: How to restore this rot?

    You can do wonders with duct tape!
    Jay

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    Default Re: How to restore this rot?

    Quote Originally Posted by Dody View Post
    As you say it's only to try it out ... as long as you promise not to start with your little girl in the boat as well for the first try
    Hi, I saw your post on your project. After seeing the ginormous task you have in your hands, it helped me understand that my project is a joke compared to what you have in your hands. It actually gave me the encouragement to just go ahead and get it done properly, as Nick so kindly took the time to describe. It very quickly made me realize I have no reason to whine.

    I like your idea, and it would probably have worked for a very short trial. And not to worry, there's no chance I'd have her onboard that thing until it has been tested and proven to be safe. And even then, only while wearing a PFD. We have a rule in the house, no one is allowed in the boat without a PFD. And she's fond of hers. Then again she's quite used to it by now, the first time she wore one in our boat, she was just 1.5 months old.

    Thanks for the idea and boa sorte com seu barco.

  21. #21
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    Default Re: How to restore this rot?

    Bravo Joolz! Making that first cut is the hardest part. It's all downhill from here
    - Chris

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    Default Re: How to restore this rot?

    Quote Originally Posted by Joolz View Post
    Hi, I saw your post on your project. After seeing the ginormous task you have in your hands, it helped me understand that my project is a joke compared to what you have in your hands. It actually gave me the encouragement to just go ahead and get it done properly, as Nick so kindly took the time to describe. It very quickly made me realize I have no reason to whine.

    I like your idea, and it would probably have worked for a very short trial. And not to worry, there's no chance I'd have her onboard that thing until it has been tested and proven to be safe. And even then, only while wearing a PFD. We have a rule in the house, no one is allowed in the boat without a PFD. And she's fond of hers. Then again she's quite used to it by now, the first time she wore one in our boat, she was just 1.5 months old.

    Thanks for the idea and boa sorte com seu barco.
    Lovely to hear this, very happy you decided on a proper repair and ... Obrigada !!!!

  23. #23
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    Default Re: How to restore this rot?

    If the bilge stringer battens are not rotten, this is not a big project! I could do the full bottom replacement in a day. Don't make a federal case out of this, it aint all that hard to do!

    If the bilge stringer battens are rotten, make it into a flower planter or a sand box for your daughter!

    Jay
    Last edited by Jay Greer; 07-23-2017 at 12:18 PM.

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    Default Re: How to restore this rot?

    Quote Originally Posted by Joolz View Post
    Well folks, after getting over the nightmarish scenario of slicing open the bottom of the little boat with a circular saw, and taking another look at the boat, I realize now that this is what makes the most sense. As Nick said, it'd more work to FB the thing and still not having a proper fix. And as cstevens said, once the proper repairs are done, I can always sell it and recover my costs, if it came to that. So it just makes sense to do it the right way.
    Still concerned with removing the keel batten without breaking it, that epoxy is there good.

    Nick, please help me understand the steps:
    - I should remove the keel batten first.
    - remove the FB tape along the side edges and the transom's bottom
    - unscrew any screw holding the portion of the floor that's to be cut out.
    - use a circular saw and make a straight cut, about a foot in length (or further, depending on how far I can see rot)

    Once the above is done I suppose the next phase would be:
    - cut a matching piece of plywood to fit - please describe what kind should be used, or would any hardware store ones do, as long as it is the same thickness?
    - add a butt block as in the pic you posted above and instructions already given.
    - once that's hardened, fibreglass the joint on the outside of the boat. if this is correct, should I use mat? how many layers would you recommend? How far should the pieces of mat extend beyond the joint?
    - fibreglass the edges along the sides of the boat as well as under the transom. How many layers would you use?
    - apply a good coat of wood primer to all bare wood (and I suppose on the FB too?). Paint several coats of marine paint (or if this works, could I just spray automotive semi gloss white paint? Have several cans of these in the house)
    - once all the painting is done, reinstall keel batten
    - apply epoxy to edges of batten and all the interior joints

    Is this correct or am I missing any steps?
    And thanks for not giving up on me when I thought I could just short-cut my way through. Took me a couple of days to get over the fact that this is a bigger job than I had anticipated. I suspect this thing will be a keeper, so might as well do it right the first time. Really appreciate the expert advice.
    This is what I would do.
    Use a screw driver or bradawl to establish the extent of the rot on the inside, then go a couple of inches further.
    Use that info to mark your cut line on the outside.

    Grind off the FG tape from the bit to be removed and from the battens surrounding the bottom about 3 inches forward of the cut. Scrape or sand off the bottom paint from 4 inch past the cut. Remove all screws that this uncovers.
    Working inside remove all of the screws securing the keel batten. sand off the varnish for 4 inches past the cut line to give clean wood to glue the butt block to.
    Back to the outside, using a thin saw, a Fein Multi Tool or similar would be best free off the keel batten.
    Cut off the bad bit of bottom. Clean up the joint faces.
    Using the best quality ply you can find, marine grade for preference, but exterior grade if there are no voids in the cores, cut your new bottom over size and the butt block (6 inches wide would be about right).
    Mark and drill pilot holes for your screws. Use two rows of staggered screws into both sides of the butt block. Glue it all back together using a waterproof glue and screw it down with countersunk stainless or non ferrous screws. As you are going to be glassing the edges I would use epoxy as you will need it anyway.
    Trim the edges of the new bottom panel, removing the glue squeeze out. Round the edges and corners so that the GRP tape lays on better.
    Tape the joints, using the same amount of tape that you ground off. Fill the weave of the tape and clean off any amine blush, refer to the Gougeon book in sharpiefan's post for the how to's.
    Refix the keel batten. If you were careful with the saw taking it off, it should go straight back on.
    Prime and paint. Your paint standards and technology differs from those in the UK so I will not offer advice about what to use. Make sure that whatever you use is compatible with the existing bottom paint by testing it on the scrap piece that you cut off.
    It really is quite difficult to build an ugly wooden boat.

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  25. #25
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    Default Re: How to restore this rot?

    Quote Originally Posted by Joolz View Post
    Well folks, after getting over the nightmarish scenario of slicing open the bottom of the little boat with a circular saw, and taking another look at the boat, I realize now that this is what makes the most sense. As Nick said, it'd more work to FB the thing and still not having a proper fix. And as cstevens said, once the proper repairs are done, I can always sell it and recover my costs, if it came to that. So it just makes sense to do it the right way.
    Still concerned with removing the keel batten without breaking it, that epoxy is there good.

    Nick, please help me understand the steps:
    - I should remove the keel batten first.
    - remove the FB tape along the side edges and the transom's bottom
    - unscrew any screw holding the portion of the floor that's to be cut out.
    - use a circular saw and make a straight cut, about a foot in length (or further, depending on how far I can see rot)

    Once the above is done I suppose the next phase would be:
    - cut a matching piece of plywood to fit - please describe what kind should be used, or would any hardware store ones do, as long as it is the same thickness?
    - add a butt block as in the pic you posted above and instructions already given.
    - once that's hardened, fibreglass the joint on the outside of the boat. if this is correct, should I use mat? how many layers would you recommend? How far should the pieces of mat extend beyond the joint?
    - fibreglass the edges along the sides of the boat as well as under the transom. How many layers would you use?
    - apply a good coat of wood primer to all bare wood (and I suppose on the FB too?). Paint several coats of marine paint (or if this works, could I just spray automotive semi gloss white paint? Have several cans of these in the house)
    - once all the painting is done, reinstall keel batten
    - apply epoxy to edges of batten and all the interior joints

    Is this correct or am I missing any steps?
    And thanks for not giving up on me when I thought I could just short-cut my way through. Took me a couple of days to get over the fact that this is a bigger job than I had anticipated. I suspect this thing will be a keeper, so might as well do it right the first time. Really appreciate the expert advice.
    To do the butt, I'd make the block, then attach half to the extant bottom, leaving half of the block exposed. Then, I would attach the replacement bottom piece of ply, fastening it all around the perimeter. You can fasten into the chines and transom framing, and into the butt block This will make it much easier to get the butt block firmly attached and centered and etc. make sure you use glue on the dyes of the ply, where they butt.

    Use what is in the boat. If it's marine ply, get some. If it's external,grade, get some of that.

    On the outside of the butt, I'd use one layer of 6oz, same as along the chines and transom joint. No need to go crazy, as it's not structural.

    Also, if you place some plastic sheet (I use cut out strips of plastic for covering tapes) over the epoxy and glass, and smooth that down, you can minimize the amount of finish work you need to do.

    Another trick is to roll out some glass tape on a piece of plastic sheet, saturate it with epoxy, and apply the whole shebang over the spot to be covered, then smooth down over the plastic. Pull the plastic after cure and you have a nice, smooth spot. I've used it with much success. The plactic sheet is cool, because you can see what's going on with the glass/resin/wood bond/matrix deal.

    Peace,
    Robert

    P.S. That my duck punt butt, by way of quailfying my opinion.

  26. #26
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    Default Re: How to restore this rot?

    Quote Originally Posted by Peerie Maa View Post
    I don't think that would work well. The rot will have created a gap under the transom, so there is nothing there at that aft edge to pass the pressure load from the bottom patch up into the transom.
    Just get an extra tube of goo.

  27. #27
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    Jul 2017
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    Default Re: How to restore this rot?

    Not sure if the above comment was intended as a joke or if there's some merit to using this goo (whatever that is) but it was what Nick said that prompted me to do the fix his way. The possibility of vertical forces not transferring to the transom should be a cause for worry. Well, maybe not so much at slow rowing speeds but I do have an electric trolling motor that I'd like to add to this thing. Seeing how nicely it pushes the 2,000lbs boat forward, I should be able to get some decent speeds out of a 7' skiff. Which would mean a good amount of upright force at the back of the boat. So yeah, having no gaps in between the transom and the back of the boat makes complete sense.

    The good news is, I have pretty much all the tools needed for the job. Have a very decent grinder with a big stone I use for welding, so this ought to take care of the existing FB nicely. Table saw at the ready, circular saw and just about all other small tools one can think of. As far as material goes I just need to buy the plywood (or I may even have some in the house, need to check) and the epoxy. Have a new FB kit and plenty of cloth and mat. Although based on the instructions by Nick, sounds like the polyester resin in the kit won't even be used (if this is the case I'll return the kit to the store for a refund).

    Time is a bit tight but I do intend to get started sometime this week. Will of course, keep this thread updated as I am sure I will need guidance along the way. Which is a great feeling as I do feel I'm in good hands here. Thanks folks, for all the help so far.

  28. #28
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    Default Re: How to restore this rot?

    ^^ Stay the course Joolz. You are on the right track and there is plenty of expertise here to help if you need it. My first boat as a boy was a flatiron skiff very much like that one, although a little larger, and planked rather than plywood. That was nearly 40 years ago now but I wish I still had it. You will have a great boat when you are done - one that your daughter will be able to enjoy for years as she grows up. Lots of adventure can be had in a boat like that.
    - Chris

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    Life is short. Go boating now!

  29. #29
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    Jul 2017
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    Default Re: How to restore this rot?

    Quote Originally Posted by cstevens View Post
    ^^ Stay the course Joolz.
    Indeed I am. But during a moment of weakness, the notion of a magic goop really seemed appealing.
    As seen in the pic, there's no turning back now. And I'm really glad I chose to listen to you experts, as otherwise I'd have missed a few spots where dumpness was trapped in. After removing the FB tape and screws holding the thin pieces of wood on the sides and at the transom, I found these to be wet inside. Arrows indicate the discolouration in the wood where moisture was sitting. There doesn't seem to have rot damage, but would sanding these and possibly spraying bleach be enough? Sure hope I don't have to replace these pieces.

    Run out of daylight but tomorrow I plan to cut the bottom along the pencil mark. When I first came here the thought of bringing a circular saw to the bottom of the boat turned my stomach but now I'm looking forward to it. As you folks so kindly explained, it truly isn't a big deal. Just annoying - and I'm referring to the FB dust that made the evening rather itchy till a shower took care of that.

    As a bonus I was able to only remove a portion of the keel batten. Believe that as long as I'm careful that I shouldn't have to remove it entirely. The middle bench would have to be removed to access some of the screws and I'd rather not do that. Not to mention it's pretty tough removing the glue from where the batten sits against the plywood. Used a few blades to cut through, with minimal damage to the plywood.

    The guy that built this used glue pretty much everywhere, so even removing the portion of the plywood may prove a bit tricky, without causing collateral damage. Will take my time and do the best I can.


  30. #30
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    Default Re: How to restore this rot?

    I'd buff the paint off and remark your line before you cut, as you will be taping over the join. You do know to let the wet wood dry right out before you put any resin or glue near it.
    It really is quite difficult to build an ugly wooden boat.

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  31. #31
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    Default Re: How to restore this rot?

    I am really impressed with the generosity of respondents to this guy's query and the patience you all have had with his trepidation at deconstruction. That is the best of what this forum is about.

    Bruce

  32. #32
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    Default Re: How to restore this rot?

    Quote Originally Posted by Peerie Maa View Post
    I'd buff the paint off and remark your line before you cut, as you will be taping over the join. You do know to let the wet wood dry right out before you put any resin or glue near it.
    Fraid just buffing the paint won't be enough, it looks like the builder put on a thick coat(s) of varnish prior to applying the paint. Looks like I'll have to grind it to bare wood. With that said, please clarify the following: is it necessary to use epoxy to lay down the fibreglass in this case? I have a FB kit with the resin ready to go. But if using epoxy is preferable, what kind? All I see in local hardware stores are the JB Welds and the like (basically a minimal amount, often no more than 25ml). If I must use epoxy, since it would adhere better to the sides (where the old FB tape was removed and is not down to bare wood) then would this product be a good candidate? It is the only one I can find that comes in a larger amount. https://www.lowes.ca/glues-epoxy/usp...rm=epoxy-resin

  33. #33
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    Default Re: How to restore this rot?

    Joolz, you definitely want to use a good epoxy system designed for what you are doing. Some reputable manufacturers are MAS, West System and System 3. People have their preferences but I've used all of those with good results. If you can't find any of these locally you can order them from various suppliers like Jamestown Distributors:

    https://www.jamestowndistributors.co...ne=1&page=GRID

    I've been using MAS FLAG medium viscosity resin and medium hardener on my current project. Works great for me and it's non-blushing, which simplifies things a bit. Details here:

    http://masepoxies.com/non-blushing-epoxy/

    It's also worth doing some reading on epoxy application. I'm not even remotely an expert so I won't make any specific recommendations but there is lots of info here on the forum and on the websites of the various manufacturers. And I'm sure other people with more knowledge than I will comment, and may have different epoxy recommendations.

    Also I will note that epoxy is VERY specific about how it is mixed and applied. You have to follow the directions exactly. Accurate measurement is critical so you will need graduated mixing cups at least. And getting a set of metering pumps is absolutely worth the money if you are going to do more than a little bit of epoxy work.
    - Chris

    https://fvpetrel.wordpress.com

    Life is short. Go boating now!

  34. #34
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    Jun 2017
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    Default Re: How to restore this rot?

    The product you gave the link for is for sticking stuff together and apparently it's meant to be used similar as what a glue does. It's not the right thing.

    If you want to bond wood with fibreglass (or fibreglass tape as in your case) together to achieve a strong and watertight result, you need Epoxy Resin and the matching hardener for it. Polyester is no good as it doesn't achieve a strong bond with the wood.
    Both Epoxy Resin and the hardener are liquids, you mix them together (1:3 or 1:5, depending on the manufacturer - info on the package and you need to be very particular to get the mixture correct!!), saturate the wood where you are bonding with it (usually the wood soaks it up a bit, it's something you really want to get a stronger bond), then you saturate the fibreglass (or fibreglass tape in your case) with the resin-mix and apply the saturated fibreglass wherever you want to bond which is your chains, try to catch the seam in the centre of the tape. Somewhere in this thread it was already mentioned: you could saturate the fibreglass on a longish piece of plastic and then stick it on with the plastic on the outside (would be the same type plastic by the way I mentioned in the beginning to try out your boat), which really works great and makes only a little mess. Another way of doing it would be to stick the fibreglass carefully on the wet Epoxy on the wood and apply more Epoxy from the outside till the fibres look clear to the eye, but you will have drips and runners all over the place and more work with sanding etc. later.

    The Epoxy I like most is West System (www.westsystem.com), but there are many other brands on the market. Try to google Epoxy Resin and see what comes up. If it isn't sold in shops nearby where you are, you can mailorder it. Normally Shipchandler have it in stock, but I don't know how this is in your area.

    Good luck!!!

    Edit: by the way, you want woven or sewn fibreglass or fibreglass-tape, not "chopped strand mat" which is cut fibres pressed together to a certain thickness.
    Last edited by Dody; 07-31-2017 at 03:10 PM.

  35. #35
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    Default Re: How to restore this rot?

    In addition to the above, epoxy laminating resin will stick to polyester. In fact Lloyds recommends it for repairing GRP layups. However it is stronger than polyester, so it is better to remove any trace of polyester (except where you are blending into the sound tape, obviously).
    It really is quite difficult to build an ugly wooden boat.

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