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Tom s/v GAIA
Whoa!!!! ------ confrontational much???
let's power down the attitudes a bit, we are all just trying to help the guy. Tom s/v GAIA
let's power down the attitudes a bit, we are all just trying to help the guy. Tom s/v GAIA
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John Dawson
Not particularly
but when someone says its what people in the trade do, I don't think thats always a positive thing. My boat is thirty years old. If a PO did a repair twenty years ago with a duration calculated to be cost-efficient for him, it doesn't serve my interests. If yards save a lot of money over a year using 'adequate' materials, thats their economics. But how much more is it going to cost one owner (me) to use optimal materials on one job on one boat? My viewpoint may seem impractical to a yard, so be it. I think I understand your rationale for using poly in nonstructural repairs, that its bond is 'good enough' for the purpose and its cheaper. I read the forum to better understand what my choices are, and you've helped me be a more informed consumer of marine services, at least.
but when someone says its what people in the trade do, I don't think thats always a positive thing. My boat is thirty years old. If a PO did a repair twenty years ago with a duration calculated to be cost-efficient for him, it doesn't serve my interests. If yards save a lot of money over a year using 'adequate' materials, thats their economics. But how much more is it going to cost one owner (me) to use optimal materials on one job on one boat? My viewpoint may seem impractical to a yard, so be it. I think I understand your rationale for using poly in nonstructural repairs, that its bond is 'good enough' for the purpose and its cheaper. I read the forum to better understand what my choices are, and you've helped me be a more informed consumer of marine services, at least.
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Tom S
Ahem -- Dennis. Just did a repair on my keel
It was mostly cosmetic and just a chunk out of the gelcoat/fiberglass covering my lead keel. But I just used some West Systems. I also epoxied some stringers and mounting platforms on my keel for a fairly heavy AC/heat unit last fall. Believe me that "sucker" ain't going **anywhere** for a good long time. I also talked to and mingled around my marina and the workers and watched what they are doing and working with and they use West Systems. As I said before maybe its my Marina (Brewers), but then again it is a first class operation and they usually only do things one way. They get some multi-million dollar yacths in here so they don't cheap out. Their customers expect them not to. Oh yeah, BTW I am also building a 8 foot wooden pram (EastPort pram) using MAS systems epoxy. (I'm about half way done and should be splashing by Memorial day -- if I can find the time) http://www.clcboats.com/boats/eastportpram.php/cart_id=54457d1a23d7a9462d9a0f0f303073e5/ I am not saying I do this for a living, but when I do something on my boat, I only do it one way... I don't cheap out. I find it really funny you are advising someone that epoxy is too expensive, when the relative difference in the costs for materials for a keel repair between Epoxy and Polyester is maybe $20-$40. Sorry, for that extra price I thinks its worth. I understand maybe you used a poor choice of words -- no worry. If you notice I didn't reply earlier and really don't have a horse in this race.And I even said " Not that a polyester repair can't be made to last" But you made some pretty bold statements and I felt it warranted to talk about my experience. (as others did) Trust me you do not "affend" me and your "sence" is not totally accurate about us just "reading". If you want to discount my experience and others that even have more experience than I do like Chris et.al. then ok. Thats the beauty of this forum, information from both side allows reading to make a balance and fully informed decision to the pro's and con's.
It was mostly cosmetic and just a chunk out of the gelcoat/fiberglass covering my lead keel. But I just used some West Systems. I also epoxied some stringers and mounting platforms on my keel for a fairly heavy AC/heat unit last fall. Believe me that "sucker" ain't going **anywhere** for a good long time. I also talked to and mingled around my marina and the workers and watched what they are doing and working with and they use West Systems. As I said before maybe its my Marina (Brewers), but then again it is a first class operation and they usually only do things one way. They get some multi-million dollar yacths in here so they don't cheap out. Their customers expect them not to. Oh yeah, BTW I am also building a 8 foot wooden pram (EastPort pram) using MAS systems epoxy. (I'm about half way done and should be splashing by Memorial day -- if I can find the time) http://www.clcboats.com/boats/eastportpram.php/cart_id=54457d1a23d7a9462d9a0f0f303073e5/ I am not saying I do this for a living, but when I do something on my boat, I only do it one way... I don't cheap out. I find it really funny you are advising someone that epoxy is too expensive, when the relative difference in the costs for materials for a keel repair between Epoxy and Polyester is maybe $20-$40. Sorry, for that extra price I thinks its worth. I understand maybe you used a poor choice of words -- no worry. If you notice I didn't reply earlier and really don't have a horse in this race.And I even said " Not that a polyester repair can't be made to last" But you made some pretty bold statements and I felt it warranted to talk about my experience. (as others did) Trust me you do not "affend" me and your "sence" is not totally accurate about us just "reading". If you want to discount my experience and others that even have more experience than I do like Chris et.al. then ok. Thats the beauty of this forum, information from both side allows reading to make a balance and fully informed decision to the pro's and con's.
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Windship
poly over epoxy
John, Tom and others, Way cool. Look, the only point I ever intended to make is that there are countless polyester repairs around the world.If done correctly their all still going strong and will be for a long time to come. Why are you guys so down on using polyester?? Are you seeing alot of failures.Is someone telling you horror stories. If so, lets talk about if you want to. I do. If you feel better about using epoxy? Have at it.But there are someplaces on a boat where even pro epoxy Professional people won't use it. It's just not necessary (like on a the keel over the ballast). Yards and I use polyester because it works great and will last the life of the boat. I see no fault in that. Thanks guys, Dennis
John, Tom and others, Way cool. Look, the only point I ever intended to make is that there are countless polyester repairs around the world.If done correctly their all still going strong and will be for a long time to come. Why are you guys so down on using polyester?? Are you seeing alot of failures.Is someone telling you horror stories. If so, lets talk about if you want to. I do. If you feel better about using epoxy? Have at it.But there are someplaces on a boat where even pro epoxy Professional people won't use it. It's just not necessary (like on a the keel over the ballast). Yards and I use polyester because it works great and will last the life of the boat. I see no fault in that. Thanks guys, Dennis
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Windship
Tom of stanford,
We have a brewers near here and it's got pretty bad rep. What you said about "cheapig out", are you saying that polyester repair's are cheating the customer? And nooooo I'm not saying, by any means, to shy away from an epoxy repair because of money. Your creating things in your head that aren't there. I said it's more expensive. It's alot more. I'd like to see you looking at a 4 or 5000 dollar repair and finding out that to do it with epoxy would cost double that because of material cost. Dennis
We have a brewers near here and it's got pretty bad rep. What you said about "cheapig out", are you saying that polyester repair's are cheating the customer? And nooooo I'm not saying, by any means, to shy away from an epoxy repair because of money. Your creating things in your head that aren't there. I said it's more expensive. It's alot more. I'd like to see you looking at a 4 or 5000 dollar repair and finding out that to do it with epoxy would cost double that because of material cost. Dennis
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Chris Burti
I'm all for discussion if it helps share info.
Seems like there might be a major semantic issue here. I'll try to clarify the language a bit and stick to proven facts instead of genaralizations and apocryphal observations. First, I was responding to a repair question from a self described novice DIY-er involving a job involving a few square feet. In that context; Polyester is an excellent laminating resin...obviously. What it is not...is a particularly good adhesive when it comes to bonding to fully cured polyester resin of the same formulation...even somewhat less so when applied to a different formulation. In order to achieve a bond on the order of 70% of the the strength of the original, you must feather the repair out something on the order of 12 to 1 in order to maximize the surface area of the bond. Generaly, more surface area = stronger bond. In thinner laminates, a high ratio contributes to a weakening of the original laminate so it becomes counterproductive. The contact thickness between the reinforcing fiber and the existing laminate is very thin. Polyester resin does not cure paricularly well in thin film. Gel-coat is a modified polyester formula that cures best in an anaerobic environment, one of the reasons for using it against the mold in the laminating process. Polyester will make a molecular bond to the green gel-coat. The area to be bonded in a repair must then be chemically cleaned in the most meticulous manner because the bond is mechanical and not molecular. The working temperatures for proper full strength curing of polyester, is a much narrower range than epoxy. Epoxy used in a repair will provide more than 80% of the strength of the original laminate under far less meticulous proceedure over a wider range of operating temperatures. If you are patching a hole in an area that is not torsionally or tensionally stressed, you could use 5200 to stick on a patch and it would likely stay there a lifetime (I may be guilty of a little hyperbole here, but, not much). If your repair is subject to these kinds of stresses, are you willing to settle for 70% in a critical area when you can get more than 80% for a few more bucks. If you are not a naval architect or engineer, do you trust your own stress analysis? I certainly am not going to recommend such to a novice. If you are talking about a $4k-5k repair, it sounds like you are talking about covering the whole keel. That would essentially be a new lamination and poly should be fine. Best regards,
Seems like there might be a major semantic issue here. I'll try to clarify the language a bit and stick to proven facts instead of genaralizations and apocryphal observations. First, I was responding to a repair question from a self described novice DIY-er involving a job involving a few square feet. In that context; Polyester is an excellent laminating resin...obviously. What it is not...is a particularly good adhesive when it comes to bonding to fully cured polyester resin of the same formulation...even somewhat less so when applied to a different formulation. In order to achieve a bond on the order of 70% of the the strength of the original, you must feather the repair out something on the order of 12 to 1 in order to maximize the surface area of the bond. Generaly, more surface area = stronger bond. In thinner laminates, a high ratio contributes to a weakening of the original laminate so it becomes counterproductive. The contact thickness between the reinforcing fiber and the existing laminate is very thin. Polyester resin does not cure paricularly well in thin film. Gel-coat is a modified polyester formula that cures best in an anaerobic environment, one of the reasons for using it against the mold in the laminating process. Polyester will make a molecular bond to the green gel-coat. The area to be bonded in a repair must then be chemically cleaned in the most meticulous manner because the bond is mechanical and not molecular. The working temperatures for proper full strength curing of polyester, is a much narrower range than epoxy. Epoxy used in a repair will provide more than 80% of the strength of the original laminate under far less meticulous proceedure over a wider range of operating temperatures. If you are patching a hole in an area that is not torsionally or tensionally stressed, you could use 5200 to stick on a patch and it would likely stay there a lifetime (I may be guilty of a little hyperbole here, but, not much). If your repair is subject to these kinds of stresses, are you willing to settle for 70% in a critical area when you can get more than 80% for a few more bucks. If you are not a naval architect or engineer, do you trust your own stress analysis? I certainly am not going to recommend such to a novice. If you are talking about a $4k-5k repair, it sounds like you are talking about covering the whole keel. That would essentially be a new lamination and poly should be fine. Best regards,
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Jim2
Windship - Dennis
Dennis - You are absolutely correct on all accounts. A polyester boat can, and should, be repaired with polyester. A properly designed and executed polyester repair can be even stronger than the original layup. The last minute saturation of the surface with styrene is an essential step. Dennis you do sound like you know and have experience with polyester boat repair. Thanks for sharing your knowledge. - Jim Hague
Dennis - You are absolutely correct on all accounts. A polyester boat can, and should, be repaired with polyester. A properly designed and executed polyester repair can be even stronger than the original layup. The last minute saturation of the surface with styrene is an essential step. Dennis you do sound like you know and have experience with polyester boat repair. Thanks for sharing your knowledge. - Jim Hague
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Windship
HELP
having read all this so far, an overiding theme seems to have emerged, the question of structural vs non-structural is of particular interest to me. The repair I'm facing is just aft of the keel(apparently the boat was run aground and the keel crunched back up into the hull)I've hung the keel so there is a small amount of pressure on the cradle and this shows a crack approx 4" by about 3/8".The crack is about 1" aft of the vertical to horizontal transition of the fiberglassed in keel (no joint as the lead is hung in the glass shell). The1978 oday 30hull looks to me to be approx 5/8" of roving woven. My buddy who owns the shop (and my go to guy in a huge way) is telling me to use mat with polester. Interestingly enough he handed me the Gougeon Brothers #22 report to read apparently not having read it himself, so if you follow all that I'm in a bit of a quandry here. Do I question my good friend,who is helping me out immeasurably, or risk a sub par ( to what ever degree) repair. I'm curious if the pro polester guys might think this an appropriate type repair for epoxy? My buddy who also does lots of repairs is of the mindset that if it was polyester to begin with than fix with same but there seems to be a lot of opinion that epoxy creates a stronger moleculer bond to aged poly HELP
having read all this so far, an overiding theme seems to have emerged, the question of structural vs non-structural is of particular interest to me. The repair I'm facing is just aft of the keel(apparently the boat was run aground and the keel crunched back up into the hull)I've hung the keel so there is a small amount of pressure on the cradle and this shows a crack approx 4" by about 3/8".The crack is about 1" aft of the vertical to horizontal transition of the fiberglassed in keel (no joint as the lead is hung in the glass shell). The1978 oday 30hull looks to me to be approx 5/8" of roving woven. My buddy who owns the shop (and my go to guy in a huge way) is telling me to use mat with polester. Interestingly enough he handed me the Gougeon Brothers #22 report to read apparently not having read it himself, so if you follow all that I'm in a bit of a quandry here. Do I question my good friend,who is helping me out immeasurably, or risk a sub par ( to what ever degree) repair. I'm curious if the pro polester guys might think this an appropriate type repair for epoxy? My buddy who also does lots of repairs is of the mindset that if it was polyester to begin with than fix with same but there seems to be a lot of opinion that epoxy creates a stronger moleculer bond to aged poly HELP
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Chris Burti
Not sure Teleman.
I'm not a repair professional, although my background includes some necessary technical expertise in the adhesive characteristics of polyester, epoxy and acrylics. I have done a goodly number of my own repairs over the decades. Some have included poly/poly, but my time is more valuable to me now and so is the assurance of work done to the best of my ability. On any job I'm likely to be willing to tackle, the savings of cost of epoxy vs. poly, just isn't worth it. I have seen (and helped correct) countless failures of DIY'er's repairs. In all fairness, I've seen far, far fewer failures from the work of pros. What you describe sounds to me like an encapsulated keel, but the damage you describe sounds more like what one would expect to see on the more common appended keel. It has been almost fifteen years since I sold out my interest in our 1983 O'Day 30. If my dubious memeory is correct (highly uncertain), I believe you may have an appended keel. If so, the polyester fairing is not structural. You should be able to properly torque the keelbolts if they and the supporting structure are undamaged and allow your pro to fair the joint with polyester. If your keel is encapsulated I would have expected the damage to be more extensive than what you describe. I would grind back the gelgoat in the direction of the crack extended in order to examine the laminate for hidden damage. I would specify epoxy in in any repair order on an encapsulated keel so damaged. Peace of mind has a price. In this case it isn't a large one.
I'm not a repair professional, although my background includes some necessary technical expertise in the adhesive characteristics of polyester, epoxy and acrylics. I have done a goodly number of my own repairs over the decades. Some have included poly/poly, but my time is more valuable to me now and so is the assurance of work done to the best of my ability. On any job I'm likely to be willing to tackle, the savings of cost of epoxy vs. poly, just isn't worth it. I have seen (and helped correct) countless failures of DIY'er's repairs. In all fairness, I've seen far, far fewer failures from the work of pros. What you describe sounds to me like an encapsulated keel, but the damage you describe sounds more like what one would expect to see on the more common appended keel. It has been almost fifteen years since I sold out my interest in our 1983 O'Day 30. If my dubious memeory is correct (highly uncertain), I believe you may have an appended keel. If so, the polyester fairing is not structural. You should be able to properly torque the keelbolts if they and the supporting structure are undamaged and allow your pro to fair the joint with polyester. If your keel is encapsulated I would have expected the damage to be more extensive than what you describe. I would grind back the gelgoat in the direction of the crack extended in order to examine the laminate for hidden damage. I would specify epoxy in in any repair order on an encapsulated keel so damaged. Peace of mind has a price. In this case it isn't a large one.
Thanks Chris
Thanks for the reply, and just to clarify it is definetly an encapsulated keel. This is my first displacement boat and I'm way farther into this than I ever expected, but so be it. It's interesting how they built her, after forming the hull with the hollow for the keel it looks as if they lowered the lead into place and while it was still suspended they filled the remaining void between the lead and the keel mold with sand then cut the rebar "handles" leaving the lead embedded in sand inside the hull. They then poured about 2" of what looks like epoxy over the top of all that to form the sump. Unfortunately as the boat sat about four years water got in and froze, thus expanding enough to break the bond between the sump and hull which allowed water to migrate into the sand. So I've cut out the cabin floor, chiseled out the sump exposed the top of the lead, sucked the water up out of the sand, and am now waiting for the weather to break to perform the repair( did I say "the" repair? this is in addition to a new fuel tank and suround, removing the wheel to grind out and replace the cockpit floor-ugh the nastiest job-for which I'm using poly and mat, replacing cabin shelving which by the way came off nicely with a 5in1 painters tool that cut the tabbing close to the hull in the void between the plywood and the hull not seperating the glass tabing from the glass hull as sugested earlier, as well as everything is off the deck and cabin top) but the hull repair is paramount which brings me back to my original query, epoxy and mat? epoxy and roving woven? poly and mat? etc. This is an important decision I need to make soon and I'm not experienced enough and still looking for more help> sorry for the long windedness but as you might imagine a project of this scope can be overwhelming for a novice such as myself Thanks Frank
Thanks for the reply, and just to clarify it is definetly an encapsulated keel. This is my first displacement boat and I'm way farther into this than I ever expected, but so be it. It's interesting how they built her, after forming the hull with the hollow for the keel it looks as if they lowered the lead into place and while it was still suspended they filled the remaining void between the lead and the keel mold with sand then cut the rebar "handles" leaving the lead embedded in sand inside the hull. They then poured about 2" of what looks like epoxy over the top of all that to form the sump. Unfortunately as the boat sat about four years water got in and froze, thus expanding enough to break the bond between the sump and hull which allowed water to migrate into the sand. So I've cut out the cabin floor, chiseled out the sump exposed the top of the lead, sucked the water up out of the sand, and am now waiting for the weather to break to perform the repair( did I say "the" repair? this is in addition to a new fuel tank and suround, removing the wheel to grind out and replace the cockpit floor-ugh the nastiest job-for which I'm using poly and mat, replacing cabin shelving which by the way came off nicely with a 5in1 painters tool that cut the tabbing close to the hull in the void between the plywood and the hull not seperating the glass tabing from the glass hull as sugested earlier, as well as everything is off the deck and cabin top) but the hull repair is paramount which brings me back to my original query, epoxy and mat? epoxy and roving woven? poly and mat? etc. This is an important decision I need to make soon and I'm not experienced enough and still looking for more help> sorry for the long windedness but as you might imagine a project of this scope can be overwhelming for a novice such as myself Thanks Frank
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Chris Burti
Several comments, Frank
First, we loved our O'Day 30. She wasn't great in light air, but an asymetrical chute or a big genny helped a bunch. We commonly get a lot of wind around here (except July and August) and she was well mannered up to about 35 knots. I think you will find your efforts rewarded. A picture would really help in terms of being able to provide more specific recommendations. I can imagine several different kinds of damage that would fit your description. So these comments tend to be a bit generalized. It is my practice to use epoxy on all repairs. I almost always keep some on hand, so it is convenient anyway. If you replace the sump bottom...Never...ever pour epoxy 2" thick in a large area. It cures in an exothermic reaction and that much mass would be a very bad thing. I would grind the old cabinet tabbing down to the hull. It doesn't take much effort and you will have a better bond regardless of the material used. Most builders use the inerior joinery as part of the structural 'framing' of the boat, so don't take it too lightly. Seal off the keel void with plastic and duct tape. Tape in an inlet and a filtered outlet. Hook your shop-vac up to the outlet and let it run on lower humidity days. This will help dry out your sand further. On the repair...considering the forces involved, I think that I would go with epoxy and bi-axial cloth if it were my boat. The old laminate may not be thick enough for woven roving. Alternatively, I would go with 10 Oz. Cloth and top it with mat to make finishing easier.
First, we loved our O'Day 30. She wasn't great in light air, but an asymetrical chute or a big genny helped a bunch. We commonly get a lot of wind around here (except July and August) and she was well mannered up to about 35 knots. I think you will find your efforts rewarded. A picture would really help in terms of being able to provide more specific recommendations. I can imagine several different kinds of damage that would fit your description. So these comments tend to be a bit generalized. It is my practice to use epoxy on all repairs. I almost always keep some on hand, so it is convenient anyway. If you replace the sump bottom...Never...ever pour epoxy 2" thick in a large area. It cures in an exothermic reaction and that much mass would be a very bad thing. I would grind the old cabinet tabbing down to the hull. It doesn't take much effort and you will have a better bond regardless of the material used. Most builders use the inerior joinery as part of the structural 'framing' of the boat, so don't take it too lightly. Seal off the keel void with plastic and duct tape. Tape in an inlet and a filtered outlet. Hook your shop-vac up to the outlet and let it run on lower humidity days. This will help dry out your sand further. On the repair...considering the forces involved, I think that I would go with epoxy and bi-axial cloth if it were my boat. The old laminate may not be thick enough for woven roving. Alternatively, I would go with 10 Oz. Cloth and top it with mat to make finishing easier.
Yeah she's a bit heavy
Chris, thanks for the words of encourgement, I'm really looking forward to sailing her. Luckily she came with 3 almost new sails including a furling 150 which being big and new and crisp should help in the light airs. As to the sump I need to do something there because the mast step is screwed into the material that was removed. Any suggestions as to what type of material to pour to top off the lead, form the sump, and provide a suitable mounting platform for the mast step? This would have to be approx. the same thickness for the mast to end up in the right place.
Chris, thanks for the words of encourgement, I'm really looking forward to sailing her. Luckily she came with 3 almost new sails including a furling 150 which being big and new and crisp should help in the light airs. As to the sump I need to do something there because the mast step is screwed into the material that was removed. Any suggestions as to what type of material to pour to top off the lead, form the sump, and provide a suitable mounting platform for the mast step? This would have to be approx. the same thickness for the mast to end up in the right place.
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Chris Burti
Sump (Frank)
Not so heavy, the main is a bit small. I suspect that if the mast were located a tiny bit forward and the boom a tad longer, she might would do better in light air without suffering in heavy. I think a good sail maker could build a better main than the N/P's that came with ours, rake the mast a touch forward to offset the increased weather helm and she would sail to her rating in most winds. As for the sump, I'm trying to figure this one out in my imagination. So. it may not make sense for your specific situation. Therefore, take it with a large lump of salt. I would use epoxy. I would grind the inside of the hull all along the joint and wipe it down thoroughly with acetone in order to get a good bond. Keep a clean fresh face on the rag to avoid contaminating the cleaned area with residual waxes, silicons and oils. I'd consider using epoxy repair compound containing chopped glass. This would be less brittle than poured epoxy and generate less heat as well. I'd apply it in several layers of about 1/4 " thick, troweled flat. If you apply each layer after the preceding one has cooled but not fully cured, you should end up with a good foundation for your mast step. I would also think it unlikely to break free again and allow water to penetrate, short of a major hard grounding. I'd suggest you get some input from your pro, he's there and can see what you are working with.
Not so heavy, the main is a bit small. I suspect that if the mast were located a tiny bit forward and the boom a tad longer, she might would do better in light air without suffering in heavy. I think a good sail maker could build a better main than the N/P's that came with ours, rake the mast a touch forward to offset the increased weather helm and she would sail to her rating in most winds. As for the sump, I'm trying to figure this one out in my imagination. So. it may not make sense for your specific situation. Therefore, take it with a large lump of salt. I would use epoxy. I would grind the inside of the hull all along the joint and wipe it down thoroughly with acetone in order to get a good bond. Keep a clean fresh face on the rag to avoid contaminating the cleaned area with residual waxes, silicons and oils. I'd consider using epoxy repair compound containing chopped glass. This would be less brittle than poured epoxy and generate less heat as well. I'd apply it in several layers of about 1/4 " thick, troweled flat. If you apply each layer after the preceding one has cooled but not fully cured, you should end up with a good foundation for your mast step. I would also think it unlikely to break free again and allow water to penetrate, short of a major hard grounding. I'd suggest you get some input from your pro, he's there and can see what you are working with.
W
Windship
keel repair
Teleman, Your friend is right. If it's made with poly, repair with poly. I am also a professional and poly is just fine. I have done a few repairs on 'punched keels' just as you describe. I think chris is right, the 30 is an externally ballasted boat.If it is ,then you'll have to cut away enough of the trailing edge fillet to allow you to do the work. If the keel is in the way then you'll have to drop the keel. Do you have enough room to do the job from the inside? The crack you mention ,first of all, is probably all of the way through the hull however I have seen the laminate seperate from layer to layer. If your's is cracked in one place, then your lucky. I have also seen multi-cracks, Also, check the area at the other end of your keel. Usually, when a keel get's punched, it pulls down on the front(leading edge fillet) and pushes up on the back(trailing edge fillet)but not always. It depends on the quality of construction and the force of the wack. Do you know how to tap with a hard plastic hammer to find delamination? When you grind you have to know how far back to grind and the only way to find that out is to see how deep the crack is,so, take the grinder with 50 grit or so and grind directly on tne crack until,in depth, it stops. You will then feather back with a ratio of 12 to 1. That is if your hull is 1/2" thick at the crack, you will have to grind back(feather)to a 6' radius. If the crack is 4" long, you will end up with an oval with an outside diameter of 12" X 16". As you grind away you will be able to see the layers of laminate and this can tell you how many peices of glass to cut.And always begin with mat and end with two layers of mat. Your boat is probably layed up with 3/4oz mat and 24oz woven roving and you should not use anything but whats already there. Do NOT use only mat! You will create a hard spot in an area where the hull flex's and the repair will fail. If poly repairs(or any repair)are done correctly, IT WON'T FAIL. And as far as a melecular bond, instead of basic adhesion, the secret is after you are done grinding and you've got all of your layers cut out, paint on styrene directly on the groung out area let almost dry, paint again, almost dry,do this 4 or 5 times then paint the area with a thin coat of resin then begin the lay-up process. Using styrene softens the laminate and DOES give a true molecular bond, though not as good as during manufacture but a molecular bond. About capping off the ballast under the sole. DO NOT pour anything in the void. That is incorrect and will probably crack and create alot of heat while curing also, it will let water past that will drain into your ballast cavity. First of all, go down to the lowest part of the keel and drill a 1/2" hole to let the water out. If you get no water then you'll have to tap(sound) the keel skin with a hard plastic hammer to find voids. When you find them go to the lowest part of the void and drill 1/4" holes to let the water out. This repair is easier but will come after the laying of the sealing membrane on top of your ballast which is there to keep water out, to keep water from seeping into the ballast cavity and to keep the ballast from being pushed up if somthing else is hit by the keel in the future. What you have to do is grind all around the turn of the keel but not deep, Just enough to remove the surface, 3" will be enough.In this instance you WILL use all mat because it is the most waterproof of the glass fabrics. It's pretty simple, just cut your mat so you have maybe 5 or 6 layers extending 1/2" to 3/4" past the previous laver.Finnish by rollong on gel-coat. Let the gel-coat start to get hard then spray on P.V.A. so it will cure. Do you have anybody who is knowlageable that can help you? The keel job (punched keel) is not easy since it's so close to the keel. As for the mast step... I wouldn't mess around with the rake of the mast. Find another O'day 30 and I'm sure the owner would let you check out the mast step. However. you will probably have to go ahead and step the mast and just jack up the foot of it or have the yard keep tention while you take measurements. Again, don't mess with the rake. Dot right, you'll be glad you did when it's all done. Dennis
Teleman, Your friend is right. If it's made with poly, repair with poly. I am also a professional and poly is just fine. I have done a few repairs on 'punched keels' just as you describe. I think chris is right, the 30 is an externally ballasted boat.If it is ,then you'll have to cut away enough of the trailing edge fillet to allow you to do the work. If the keel is in the way then you'll have to drop the keel. Do you have enough room to do the job from the inside? The crack you mention ,first of all, is probably all of the way through the hull however I have seen the laminate seperate from layer to layer. If your's is cracked in one place, then your lucky. I have also seen multi-cracks, Also, check the area at the other end of your keel. Usually, when a keel get's punched, it pulls down on the front(leading edge fillet) and pushes up on the back(trailing edge fillet)but not always. It depends on the quality of construction and the force of the wack. Do you know how to tap with a hard plastic hammer to find delamination? When you grind you have to know how far back to grind and the only way to find that out is to see how deep the crack is,so, take the grinder with 50 grit or so and grind directly on tne crack until,in depth, it stops. You will then feather back with a ratio of 12 to 1. That is if your hull is 1/2" thick at the crack, you will have to grind back(feather)to a 6' radius. If the crack is 4" long, you will end up with an oval with an outside diameter of 12" X 16". As you grind away you will be able to see the layers of laminate and this can tell you how many peices of glass to cut.And always begin with mat and end with two layers of mat. Your boat is probably layed up with 3/4oz mat and 24oz woven roving and you should not use anything but whats already there. Do NOT use only mat! You will create a hard spot in an area where the hull flex's and the repair will fail. If poly repairs(or any repair)are done correctly, IT WON'T FAIL. And as far as a melecular bond, instead of basic adhesion, the secret is after you are done grinding and you've got all of your layers cut out, paint on styrene directly on the groung out area let almost dry, paint again, almost dry,do this 4 or 5 times then paint the area with a thin coat of resin then begin the lay-up process. Using styrene softens the laminate and DOES give a true molecular bond, though not as good as during manufacture but a molecular bond. About capping off the ballast under the sole. DO NOT pour anything in the void. That is incorrect and will probably crack and create alot of heat while curing also, it will let water past that will drain into your ballast cavity. First of all, go down to the lowest part of the keel and drill a 1/2" hole to let the water out. If you get no water then you'll have to tap(sound) the keel skin with a hard plastic hammer to find voids. When you find them go to the lowest part of the void and drill 1/4" holes to let the water out. This repair is easier but will come after the laying of the sealing membrane on top of your ballast which is there to keep water out, to keep water from seeping into the ballast cavity and to keep the ballast from being pushed up if somthing else is hit by the keel in the future. What you have to do is grind all around the turn of the keel but not deep, Just enough to remove the surface, 3" will be enough.In this instance you WILL use all mat because it is the most waterproof of the glass fabrics. It's pretty simple, just cut your mat so you have maybe 5 or 6 layers extending 1/2" to 3/4" past the previous laver.Finnish by rollong on gel-coat. Let the gel-coat start to get hard then spray on P.V.A. so it will cure. Do you have anybody who is knowlageable that can help you? The keel job (punched keel) is not easy since it's so close to the keel. As for the mast step... I wouldn't mess around with the rake of the mast. Find another O'day 30 and I'm sure the owner would let you check out the mast step. However. you will probably have to go ahead and step the mast and just jack up the foot of it or have the yard keep tention while you take measurements. Again, don't mess with the rake. Dot right, you'll be glad you did when it's all done. Dennis
R
robert taylor
lead is toxic
one thing that has been overlooked is that lead is really toxic, especially if you are grinding it. i would use a respirator and a grinder with a vacuum accumulator. good luck. ps i don't think it makes that much difference what you use, but there is no guess work with the west dispensers (they also sell it in slow, medium, and fast cure. the slower the cure, the less brittle the repair will be. it will also give you time to apply all layers at once).
one thing that has been overlooked is that lead is really toxic, especially if you are grinding it. i would use a respirator and a grinder with a vacuum accumulator. good luck. ps i don't think it makes that much difference what you use, but there is no guess work with the west dispensers (they also sell it in slow, medium, and fast cure. the slower the cure, the less brittle the repair will be. it will also give you time to apply all layers at once).
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