Island Time 1,240 Posted May 22, 2014 Share Posted May 22, 2014 Ok, a question for the paint and glassing experts. I have Island Time out of the water at the moment, for a long overdue antifouling job, and general maint. The keel is the main project this time. Very thick, old antifouling to take off. Mostly done now. The keel's bottom 3rd is all lead, not encased. The top 3rd is fibreglass, and the middle 3rd seems to be faired with a grey, slightly porous filler. Both the lead and the filler have some pinholes in them. I have always had paint adhesion issues on the bottom 2/3rds (the lead and the filler. There are beads of water coming out of the filler in a few places, and a bit from the filler-lead joint. So far I have sanded off all the paint on the bottom 2/3rds of the keel, up to the beginning of where the fiberglass starts. (there is some area of lead on the bottom of the keel (winged bulb) that I cannot get to, as the boat is sitting on it... As the paint has (and is still) well adhered from there up, I have not removed it further up. My intention is to F/glass over the filler, down to, and perhaps overlapping the lead by 50mm. My 1st question is this should I etch prime the lead before applying the fibreglass, or will the epoxy stick to the lead ok? It's rough sanded with 40 grit. The lead section will be etch-primed, epoxy painted (interprotect or similar) before antifouling again. The Fibre glass part, including the new glass over the filler, will be primed and interprotected as well, before antifouling. That is the plan. Any other suggestions, or a better system??? Another day of sanding today, going down there now.... The only time when I wish the boat was a dingy! Thanks Matt Link to post Share on other sites
Guest Posted May 23, 2014 Share Posted May 23, 2014 Read between the lines The keel is the main project this time. Very thick, old antifouling to take off. Mostly done now. The keel's bottom 3rd is all lead, not encased. The top 3rd is fibreglass, and the middle 3rd seems to be faired with a grey, slightly porous filler. Both the lead and the filler have some pinholes in them. I have always had paint adhesion issues on the bottom 2/3rds (the lead and the filler. There are beads of water coming out of the filler in a few places, and a bit from the filler-lead joint. - The original set up may have been done with a polyester based filler ( resin or gel-coat extended ). If it was un-waxed you will have the adhesion issues similar to what you have described. When sanding it does it smell sweet like an ester ? If your not sure pop round next week and ill show your nose so to speak. So far I have sanded off all the paint on the bottom 2/3rds of the keel, up to the beginning of where the fiberglass starts. (there is some area of lead on the bottom of the keel (winged bulb) that I cannot get to, as the boat is sitting on it... As the paint has (and is still) well adhered from there up, I have not removed it further up. My intention is to F/glass over the filler, down to, and perhaps overlapping the lead by 50mm. - lap 50mm minimum, more like 75mm. I would try and use around 900gms of glass as well. My 1st question is this should I etch prime the lead before applying the fibreglass, or will the epoxy stick to the lead ok? It's rough sanded with 40 grit. - The epoxy will stick to the lead fine if it is fresh sanded and still looks glossy - if it dulls off it has started to oxide. Most readily available epoxy primers are what I would call build primers and technically would be weaker than the epoxy/glass bond. -- Note add a little glue powder to the resin brew when glassing it will help it stay up and be less pin holy through the glass weave. The lead section will be etch-primed, epoxy painted (interprotect or similar) before antifouling again. - all good, again make sure the lead is fresh sanded. I've herd old school stories of people sanding painting and then wire brushing when the paint is still wet. A tad extreme in my experience. The Fibre glass part, including the new glass over the filler, will be primed and interprotected as well, before antifouling. - all good That is the plan. Any other suggestions, or a better system??? Another day of sanding today, going down there now.... The only time when I wish the boat was a dingy! Thanks Matt Link to post Share on other sites
Guest Posted May 24, 2014 Share Posted May 24, 2014 As per FNG and... If polyester filler then ensure it is washed to remove salts, also then dry to below 15% moisture content. I usually wrap the area with black plastic, sealed with tape and a drip hole at the lowest corner and the periodically remove to air. .... until MC obtained. You can wrap and introduce a blower to dry is time is of the essence. Use epoxy resin and ensure thorough clean down/de dust before application. Cross hatch Sand with 60/80 grit to open up filler, expose clean filler. This will provide. Good key with glass/resin. Lead, as FNG says, has to be keyed (cross hatch with 60 grit. and clean, then I would use a epoxy primer like Altex no 1 grey, then a epoxy undercoat straight over the top ( this can be sanded with 240 320 for desired smoothness... aye Sow1d ). Primers wet out the substrate and key better than primer u/coats But you can use just about any epoxy. But not Durepox. The is is a isocyanate/urethane modified epoxy. Epiglass used to have a red epoxy, 118 I think?, designed for lead. It was good stuff. Also - is the keel constructed this way ( glassed top 1/3 - then no glass) for a reason?... designed break point?, torsional stress engineering?... or something?. I too would glass it but maybe the builders/designer have a reason for this setup? Link to post Share on other sites
Island Time 1,240 Posted May 24, 2014 Author Share Posted May 24, 2014 Thanks for the replies. So my basic ideas are OK, that's good. The keel was made this way, not sure why. The glass should have been down to the lead IMO, but wasn't. Happy too go 75 mm onto lead. 900 GMs fng? Remember I'm not a boat builder! thats like 3 layers of 10 ounce cloth? Would you recommend woven or chopped strand mat? Glue powder a good hint, the. Mixture ratio? As it's a vertical surface, I was thinking of this method, using epoxy resin. Paint it on, wait until tacky, stick on the cloth, wet out. Wait until firm but not set ( can mark/dent with fingernail) repeat 2 more x, so three layers of cloth applied. Then another coat, epoxy with lots of microballoons to help ease the fairing.. Total build needs 3-4 mm. Is that a good idea, or another method? I think the filler is just for fairing - looks like ferro, but soft - easy to sand. It is definitely pourus, you can see pinholes in it. Not ment to get wet I reckon. Thanks for your help guys, I appreciate it! Matt Link to post Share on other sites
Guest Posted May 24, 2014 Share Posted May 24, 2014 900 GMs fng? Remember I'm not a boat builder! thats like 3 layers of 10 ounce cloth? Would you recommend woven or chopped strand mat? - 3 layers of 10oz cloth will be fine. -csm is not ideal with epoxy, and should be powder bonded ( ha work that one out ) Glue powder a good hint, the. Mixture ratio? - still needs to be brush able, just enough to colour the resin As it's a vertical surface, I was thinking of this method, using epoxy resin. Paint it on, wait until tacky, stick on the cloth, wet out. Wait until firm but not set ( can mark/dent with fingernail) repeat 2 more x, so three layers of cloth applied. Then another coat, epoxy with lots of microballoons to help ease the fairing.. Total build needs 3-4 mm. - Do all the glassing at once, you may be waiting a bloody long time for the epoxy to go tacky. - the time the glass takes to tack off enough for 'you' to successfully apply the microballoons will be too long for the lead oxidation. - I would recommend that you peelply the glass job. Then remove that for the fuller stage the next day. this will allow you to re sand the exposed lead for adhesion. Is that a good idea, or another method? -There is no 'proper' quick fix at your level, especially in winter. Link to post Share on other sites
Island Time 1,240 Posted May 24, 2014 Author Share Posted May 24, 2014 OK, thx. The peel ply is a good idea. I was just thinking about, since the job is vertical, the tendency of the resin to sag, esp if thick, which it will be with 3 layers of cloth to wet out. I guess the peel ply will help that. Never used it before, new things are good. To do all the glass at once, so there is a chemical bond is the idea. Sorry if I gave the wrong impression. By the time I do the fairing coat, with the microballoons, I expect that it will be on top of the previous glass, not the lead, but I'll be sure the lead is shiney before anything is coated over it. Winter here is pretty much the same temps as December in Wellington! I built a few Kevlar kayaks down there in winter! Thanks again! Link to post Share on other sites
Battleship 100 Posted May 24, 2014 Share Posted May 24, 2014 When glassing a large section on a vertical surface you can just give it an extra large overlap at the top and tape it in place to stop it ending up on the ground, then once set trim it off with scissors and tidy the edge with a disc sander or similar. On the keel for the SR I just wrapped the cloth around the front used tape on the top and used a couple of battens covered in packing tape clamped on the trailing edge to hold in in place which worked well. Link to post Share on other sites
Island Time 1,240 Posted May 25, 2014 Author Share Posted May 25, 2014 Some pics from today. Keel sanding is finished, rudder done, working on hull while keel dries, and a few blisters to fix on the rudder... And a closeup - sorry, just from a cellphone. Most of those water lines are from rain. The one in the middle is not a crack. Zoom in for a better look. Link to post Share on other sites
Guest Posted May 25, 2014 Share Posted May 25, 2014 you probably don't want to here this, but if it was my boat I would grind out that middle layer of filler to see what's going on underneath. Even if it's just to replace that filler with an epoxy based system. Link to post Share on other sites
Island Time 1,240 Posted May 25, 2014 Author Share Posted May 25, 2014 I must admit to having the same thoughts myself! The problem is, that filler seems to be what fills the top part of the keel as well, behind the glass. I'm guessing there must be some sort of steel frame in there as well, to transfer the loads. There are 10 keel bolts, one big one at the front, one at the back, and two rows of 4. Its never moved, there are no cracks. The builders say the bolts are j bolts, cast into the lead. Cranking on a very big strongarm and socket, no more movement can be be got on the keel bolt nuts - they are not seized, just as tight as I can get them. If I had broken a bolt, or even moved one substantially, I'd have to look further, but they seem fine. To remove all the filler would be very difficult, and require the removal of all the glass at the top, and complete re-profiling of the keel. I think I'll let it dry for a bit (week or two), and see how it progresses. If I had to rebuild the keel, I'd go to a more modern design. Financially I'm not in a position to do that at this point. This keel received a huge impact - slowing the boat from 7 knots to 1, and breaking 2 engine mounts, yet it shows no sign of structural damage. Impact was right at the top of the keel leading edge (a log, we think). I'll see how it looks after queens birthday.... Link to post Share on other sites
Guest Posted May 25, 2014 Share Posted May 25, 2014 Q: is the filler hard or soft?... can you dig a screw driver into it? Looks hard to me. If it is polyester and softish ( poor quality / poorly catalyzed) then this could cause glass adeshion issues. How .long has water been oozing out? Or how much has oozed out? Water indicates there may be areas that are holding water. There are specialized products that can be applied onto the surface that absorb into the smallest of cracks/ voids then expand and fill/secure the gap. In The building industry we use Xypex. Watch this video to see how itworks. This is for concrete but I think there is a fibreglass one too? Xypex is brilliant. http://www.xypex.com/products Link to post Share on other sites
Island Time 1,240 Posted May 26, 2014 Author Share Posted May 26, 2014 Thanks for your Interest sailorx, Its quite hard, - you'd have to hammer a screwdriver in, but you could scratch it - its softer that epoxy. There are some fibres in it. The boat has been out of the water for a week tomorrow. To begin with, there were several places water was slowly dripping out. That has stopped, now just a couple of damp spots, so I think its drying OK. It must be pretty crush resistant, as where we hit the log, it cracked the glass cover (6-7mm thick there), but did no apparent damage to the filler. This was, of course, then a point of entry for the water... I'll have a look at xypex, thx. Link to post Share on other sites
Guest Posted May 26, 2014 Share Posted May 26, 2014 Thanks for your Interest sailorx, Its quite hard, - you'd have to hammer a screwdriver in, but you could scratch it - its softer that epoxy. There are some fibres in it. The boat has been out of the water for a week tomorrow. To begin with, there were several places water was slowly dripping out. That has stopped, now just a couple of damp spots, so I think its drying OK. It must be pretty crush resistant, as where we hit the log, it cracked the glass cover (6-7mm thick there), but did no apparent damage to the filler. This was, of course, then a point of entry for the water... I'll have a look at xypex, thx. Could be vinylester?. As long as it is sound, dry and filled then glassed (epoxy resin) then it should be all OK. If its survived all that with no glass it cannot be weaker with glass. (Presumimg bolts are all OK) But as FNG says... could be worth a look beneath the filler. Industrial XRay?, just to be sure. Good article... http://www.sailnet.com/forums/gear-main ... cerns.html Link to post Share on other sites
Island Time 1,240 Posted May 26, 2014 Author Share Posted May 26, 2014 Yep, seen that info before. It is a good article If the bolts could be tightened more, I'd be concerned. They can't - nothing is moving, no cracks, rust marks etc etc. The Cat 1 inspector I used in Wellington was a structural engineer. His comment about my keel was to torque the bolts as much as I could, and see if I could break one. If I did, the keel would have to come off. His comment was " there are a lot of well placed bolts, even one broken one would not be an issue, but would be an indication there was a problem and the rest would have to be inspected" I've sort of stuck to that, and nothings moving! I trust that that means all is well.... Link to post Share on other sites
Island Time 1,240 Posted June 19, 2014 Author Share Posted June 19, 2014 OK, finished!! and Fixed the glass issue, added glass down over lead, repainted (under waterline only), re anti fouled, new anodes, changed back to the Kiwi Prop, new front engine mounts, relaunched today! Link to post Share on other sites
Guest Posted June 19, 2014 Share Posted June 19, 2014 Is that anode on the lead? Do they work when placed on that or is there straps running down to it? Nice to be back floating I bet. Link to post Share on other sites
Island Time 1,240 Posted June 19, 2014 Author Share Posted June 19, 2014 Yep, anode on the lead. Works fine, but the keel is attached to the grounding system... Link to post Share on other sites
sow1ld 2 Posted June 19, 2014 Share Posted June 19, 2014 Looks pretty time to go for a long cruise just to be sure it all works Link to post Share on other sites
Guest Posted June 19, 2014 Share Posted June 19, 2014 Lookimg swish! How's the perfomamce / stiffness with the wings? I hear they perform really well. Link to post Share on other sites
Island Time 1,240 Posted June 19, 2014 Author Share Posted June 19, 2014 Well X, I'm probably not the right person to ask - I'm biased! Performance is about the same as a 1220, although the boat is a little smaller. Draft, displacement and sail area a bit less as well. I've been really happy with her, and for the size and $ I've not seen another cruiser I'd rather have.... Link to post Share on other sites
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