On the interior edge of the forward hatch I have a crack that goes all the way around. This is a new boat for me and I don't know the cracks origin. I can stick a clothes hanger into this crack at least 12" without encountering any resistance. Is this part of the cabin roof hollow on a 79 and if so can I just fill it with expanable foam injected into the crack to make it more ridged? I have gel coat cracks up top in this area. Thanks Mike
cabin roof on a 79 25footer
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Filling the deck
The easiest, most sensible way to fix this is also time-proven and effective. I had a lot of this on my '74 boat-- it's caused by decay of the balsa core inside the deck (between the molded outer surface and the 'liner' inside). These two layers alone, without the integrity of the balsa core, are not sufficiently strong to hold even your weight, let alone the panel stresses the rigged boat in operation imposes on them. First, fill the gelcoat cracks and fair them to your liking. This will be easier to do before you fill the inner voids because there will be somewhere for the filler to go. Use gelcoat with wax and maybe a little filler, like Aerosil. Next, go below and investigate ALL potential holes through the inner layer-- hardware mounting holes, cracks, chips, seams, etc., and either fill with something easy like Marine-Tex or even patch them with duct tape (as I did). Any negligence here will lead to a dripping mess later. Then walk or crawl around on the deck, identifying which places are flexing most. Drill a series of 1/4" holes in the area-- do it in the painted/nonskid places rather than in the white gelcoat because it'll be easier to fill and clean up the holes. The holes must go through the TOP later but NOT the bottom one. Put tape on the drill bitt at about 3/16" inch and observe that while drilling. Using WEST epoxy and a syringe, pump the living heck out it with epoxy. Originally I did this with acetone thinning out the epoxy, because I thought it would run farther into the rotten/voided area. This is not necessary. Doing it on a warm day, in the sun, or with epoxy warmed up (like spending a night in the heater room) will do just as well. As long as you see it disappearing down the holes, and you don't see it dripping out inside the cabin, you're not done filling. I put in about a quart or more and had two (minor but messy) leaks. Be careful it doesn't ooze out from other holes above deck too. Someone should follow you with duct tape and a rag. When you're done all that, simply fill the epoxy holes with Marine-Tex or something and repaint the nonskid parts. You'll be surprised how far wood-penetrating epoxy will go-- you don't need as many holes as you think. When it's all kicked off, walk around the deck and see if it still moves anywhere-- if so, repeat the process for those places. I filled three separate places on my deck-- to either side of the hatch and to port of the mast step. This deck is now so stiff you can hold a teen dance on it. You can see why my dad wanted that domed foredeck because it's like an arch bridge when it's as stiff as it was intended to be. This solution sounds deplorably low-tech, but it is the industry standard way of fixing rotten balsa/foam core. The only alternative is to chop out large sections of the deck to replace the balsa, fair it up to pretend to be factory-spec in appearance, and then probably face the same problem later. The epoxy adds a little weight, but it does NOT have to add strength. The balsa isn't there for strength either-- it is only a spacer between two fiberglass layers, making the deck like a girder structure. Anything that will bond to both layers and won't soak up water and decay will work. You don't get better than epoxy for this job. I've recently done this job on the plywood deck of a 27-year-old Cherubini 44 and with the same result. It saved us from replacing huge sections of deck we really didn't have to open up after all. And you can hold a dance on it. JC 2 H25 Mk 1 Diana Burlington NJ jcomet@aol.com
The easiest, most sensible way to fix this is also time-proven and effective. I had a lot of this on my '74 boat-- it's caused by decay of the balsa core inside the deck (between the molded outer surface and the 'liner' inside). These two layers alone, without the integrity of the balsa core, are not sufficiently strong to hold even your weight, let alone the panel stresses the rigged boat in operation imposes on them. First, fill the gelcoat cracks and fair them to your liking. This will be easier to do before you fill the inner voids because there will be somewhere for the filler to go. Use gelcoat with wax and maybe a little filler, like Aerosil. Next, go below and investigate ALL potential holes through the inner layer-- hardware mounting holes, cracks, chips, seams, etc., and either fill with something easy like Marine-Tex or even patch them with duct tape (as I did). Any negligence here will lead to a dripping mess later. Then walk or crawl around on the deck, identifying which places are flexing most. Drill a series of 1/4" holes in the area-- do it in the painted/nonskid places rather than in the white gelcoat because it'll be easier to fill and clean up the holes. The holes must go through the TOP later but NOT the bottom one. Put tape on the drill bitt at about 3/16" inch and observe that while drilling. Using WEST epoxy and a syringe, pump the living heck out it with epoxy. Originally I did this with acetone thinning out the epoxy, because I thought it would run farther into the rotten/voided area. This is not necessary. Doing it on a warm day, in the sun, or with epoxy warmed up (like spending a night in the heater room) will do just as well. As long as you see it disappearing down the holes, and you don't see it dripping out inside the cabin, you're not done filling. I put in about a quart or more and had two (minor but messy) leaks. Be careful it doesn't ooze out from other holes above deck too. Someone should follow you with duct tape and a rag. When you're done all that, simply fill the epoxy holes with Marine-Tex or something and repaint the nonskid parts. You'll be surprised how far wood-penetrating epoxy will go-- you don't need as many holes as you think. When it's all kicked off, walk around the deck and see if it still moves anywhere-- if so, repeat the process for those places. I filled three separate places on my deck-- to either side of the hatch and to port of the mast step. This deck is now so stiff you can hold a teen dance on it. You can see why my dad wanted that domed foredeck because it's like an arch bridge when it's as stiff as it was intended to be. This solution sounds deplorably low-tech, but it is the industry standard way of fixing rotten balsa/foam core. The only alternative is to chop out large sections of the deck to replace the balsa, fair it up to pretend to be factory-spec in appearance, and then probably face the same problem later. The epoxy adds a little weight, but it does NOT have to add strength. The balsa isn't there for strength either-- it is only a spacer between two fiberglass layers, making the deck like a girder structure. Anything that will bond to both layers and won't soak up water and decay will work. You don't get better than epoxy for this job. I've recently done this job on the plywood deck of a 27-year-old Cherubini 44 and with the same result. It saved us from replacing huge sections of deck we really didn't have to open up after all. And you can hold a dance on it. JC 2 H25 Mk 1 Diana Burlington NJ jcomet@aol.com
Tedious, but I am with JC on this one.
I cut out the inner liner and replaced the rotten core in a big area aft of the mast, maybe 4X5 or so. Basically side to side and from the mast back almost to the ompainonway. Forward of the mast I drilled the holes and will inject epoxy. Diffrence for me is that I drilled thru. I had already oversized the holes for all the hardware which requires drilling thru so I figured a few more holes won't matter. Most of the ovehead has been reglassed anyway, any holes that did'nt get covered will get a bit of tape before I fill all of them. Hardware removal required 168 holes to be filled. What's a dozen or so more matter!!!!! Charlie
I cut out the inner liner and replaced the rotten core in a big area aft of the mast, maybe 4X5 or so. Basically side to side and from the mast back almost to the ompainonway. Forward of the mast I drilled the holes and will inject epoxy. Diffrence for me is that I drilled thru. I had already oversized the holes for all the hardware which requires drilling thru so I figured a few more holes won't matter. Most of the ovehead has been reglassed anyway, any holes that did'nt get covered will get a bit of tape before I fill all of them. Hardware removal required 168 holes to be filled. What's a dozen or so more matter!!!!! Charlie
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