My 1992 H28 has a leak in the "skylight" above the salon table. Has anyone removed and rebedded this "skylight?" What is the best approach?
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h29.5 skylight
Not sure if we are talking about the same skylight here, but we did take off the hood this past year and cleaned us the skylight and other recesses areas (man was it dirty in there). I recaulked a couple of areas. Not a hard job, just cut away the old calk/silicone, unscrew the hood and safely liftoff the hood and stow it safely until you are ready to reattach and re-silicone.
Not sure if we are talking about the same skylight here, but we did take off the hood this past year and cleaned us the skylight and other recesses areas (man was it dirty in there). I recaulked a couple of areas. Not a hard job, just cut away the old calk/silicone, unscrew the hood and safely liftoff the hood and stow it safely until you are ready to reattach and re-silicone.
What do you mean by "hood"?
Are you talking about the hood over the sliding companionway hatch? I am talking about a "fixed port" that is in the middle-top of the cabin roof between the mast and the companionway slider. Maybe I should take my hood off also.
Are you talking about the hood over the sliding companionway hatch? I am talking about a "fixed port" that is in the middle-top of the cabin roof between the mast and the companionway slider. Maybe I should take my hood off also.
3M
the silicone your looking for is a 3m product available from pompanette.com , Im not sure which one ,but the people at pompanette can help, they also carry replacement parts for most models, it should be a bomar hatch.
the silicone your looking for is a 3m product available from pompanette.com , Im not sure which one ,but the people at pompanette can help, they also carry replacement parts for most models, it should be a bomar hatch.
contact Hunter. They have the product
Steve: Contact Hunter, they have the product that you want to use. I think it is 795 or 995, they will tell you. When you want to remove the old sky light, just get a piece of heavy fishing line (like weed eater stuff). Start a hole in the corner of the existing caulking so you can fish the line through. Then get a buddy to help you. Tie a stick on each end of the fishing line and cut out the existing sky light. Then you will need to clean the opening and the sky light to remove the old caulking. Be sure to mask off the area (above and below) when reinstalling. You also want to be sure that the sky light is totally covered with masking tape. Once the caulk has setup you can remove the masking and you should be good to go.
Steve: Contact Hunter, they have the product that you want to use. I think it is 795 or 995, they will tell you. When you want to remove the old sky light, just get a piece of heavy fishing line (like weed eater stuff). Start a hole in the corner of the existing caulking so you can fish the line through. Then get a buddy to help you. Tie a stick on each end of the fishing line and cut out the existing sky light. Then you will need to clean the opening and the sky light to remove the old caulking. Be sure to mask off the area (above and below) when reinstalling. You also want to be sure that the sky light is totally covered with masking tape. Once the caulk has setup you can remove the masking and you should be good to go.
Yes I Have... Better Read!
Here is a couple of think NOT to do. Do not only re-caulk under the skylight. (it will stop the leak into the cabin but not into the wood deck core.) The old hatch is going to be very hard to remove. Use a rasor knife to cut the old caulk out. The if you have too use a red devil scapper and a hammer to pre skylight free. Be carefull the old plexaglass will break. Look for cracks in the old plexaglass. They will leak. Hunter sells a new skylight for $177. Then do not predrill the holes. They sold me a jet black one that does not pass light. (what good is that!) The told me they make it right, we'll see. NOTE!: If you get a new plexaglass skylight, you need to sand the side where you caulk it in. These plexaglass shylights STINK! They may be pretty but they can leak into the wood core...
Here is a couple of think NOT to do. Do not only re-caulk under the skylight. (it will stop the leak into the cabin but not into the wood deck core.) The old hatch is going to be very hard to remove. Use a rasor knife to cut the old caulk out. The if you have too use a red devil scapper and a hammer to pre skylight free. Be carefull the old plexaglass will break. Look for cracks in the old plexaglass. They will leak. Hunter sells a new skylight for $177. Then do not predrill the holes. They sold me a jet black one that does not pass light. (what good is that!) The told me they make it right, we'll see. NOTE!: If you get a new plexaglass skylight, you need to sand the side where you caulk it in. These plexaglass shylights STINK! They may be pretty but they can leak into the wood core...
Use "Bump Ons" under the Skylight
If/when you order your skylight from Hunter be sure to ask them about "bump ons". These are small (about 1/4" square x ~1/16" thick) neoprene pads that the skylight rests on. Sealing a plexiglass insert into a fiberglass-wood core deck isn't just slap-it-in and shoot the sealant on. You need to understand how the "system" works. The two materials have different coeficients of expansion and therefore require a thoughtful approach. ONLY put sealant on the ENDS of the plexiglass. NEVER put sealant UNDER the plexiglass. The sealant MUST act like a rubber band and be able to expand and contract. As the previous poster said, sand the ENDs of the plexiglass AND the fiberglass where the sealant is to adhere. Do not sand the fiberglass under the plexiglass because you don't want any sealant there. That is where the bump ons go. This is an "engineering system" - check out the Dow web site for the sealant. I used Dow 995 (instead of the 795 that Hunter used). Download and read the literature before you start tearing into the project. By the way, black holds up better than white under UV. Secret: to keep the sealant from flowing under the plexiglass consider puting a small backer rod at the bottom of the joint because it makes life easier. If you can get a small backer rod, say 1/4" dia or smaller, use a sheetrock knife and cut a larger one in half as necessary. This is foam so it squishes easily. Hope this helps.
If/when you order your skylight from Hunter be sure to ask them about "bump ons". These are small (about 1/4" square x ~1/16" thick) neoprene pads that the skylight rests on. Sealing a plexiglass insert into a fiberglass-wood core deck isn't just slap-it-in and shoot the sealant on. You need to understand how the "system" works. The two materials have different coeficients of expansion and therefore require a thoughtful approach. ONLY put sealant on the ENDS of the plexiglass. NEVER put sealant UNDER the plexiglass. The sealant MUST act like a rubber band and be able to expand and contract. As the previous poster said, sand the ENDs of the plexiglass AND the fiberglass where the sealant is to adhere. Do not sand the fiberglass under the plexiglass because you don't want any sealant there. That is where the bump ons go. This is an "engineering system" - check out the Dow web site for the sealant. I used Dow 995 (instead of the 795 that Hunter used). Download and read the literature before you start tearing into the project. By the way, black holds up better than white under UV. Secret: to keep the sealant from flowing under the plexiglass consider puting a small backer rod at the bottom of the joint because it makes life easier. If you can get a small backer rod, say 1/4" dia or smaller, use a sheetrock knife and cut a larger one in half as necessary. This is foam so it squishes easily. Hope this helps.
Just rebedded mine
I also have a 92 H-28, and my skylight leaked as well. I'm sure there are several ways to attack this repair, maybe some are better than mine, but I've had no further leaks, and it looks good. 1. Remove the pebbled section of plexiglass on the cabin top. Place a drop cloth under the skylight. 2. Remove all the screws from around the top of the skylight. There is probably some type of black goop covering the screw heads, but they're under there; you just have to dig 'em out. 3. Use a thin, sharp putty knive to break the seal around the plexiglass. This takes a while, but you'll probably have to work all the way around the perimeter, from both top and bottom. 4. Pry out the skylight. Do it slowly, a little bit at a time; you'll get there. 5. Scrape out as much of the old bedding compound as possible, and try to protect your topsides. Hunter used some type of horrible black sealant, that turns to tar after about 10 years or so. Use a chemical stripper that does not attack fiberglass to strip the rest. You'll probably have to use a Scotch-Brite pad at the very least. Thoroughly clean up the stripper and neutralize the residue w/ water followed by a light solvent (Check Interlux website: yachtpaint.com). 6. Rebed the sill with white, marine silicone or polysulfide. You'll need at least two 10-oz. tubes for a caulking gun. 7. Gently place the skylight back in the sill, and turn the screws until they're just threaded. Do not overtighten! 8. Go home. You don't want to tighten the skylight down until the sealant sets. What you've just done is built a solid, flexible gasket. 9. Mask the topsides and skylight, and fill any voids that are evident from the top, smoothing the surface as you go. You'll need to work quickly. I use a cup of water with a little dish-washing soap to dampen my finger for a smooth finish. Get the masking tape off before the sealant sets. 10. Check the Nov./Dec. 2004 edition of Good Old Boat Magazine, page 14, for a great article on sealants and adhesives. Website address attached.
I also have a 92 H-28, and my skylight leaked as well. I'm sure there are several ways to attack this repair, maybe some are better than mine, but I've had no further leaks, and it looks good. 1. Remove the pebbled section of plexiglass on the cabin top. Place a drop cloth under the skylight. 2. Remove all the screws from around the top of the skylight. There is probably some type of black goop covering the screw heads, but they're under there; you just have to dig 'em out. 3. Use a thin, sharp putty knive to break the seal around the plexiglass. This takes a while, but you'll probably have to work all the way around the perimeter, from both top and bottom. 4. Pry out the skylight. Do it slowly, a little bit at a time; you'll get there. 5. Scrape out as much of the old bedding compound as possible, and try to protect your topsides. Hunter used some type of horrible black sealant, that turns to tar after about 10 years or so. Use a chemical stripper that does not attack fiberglass to strip the rest. You'll probably have to use a Scotch-Brite pad at the very least. Thoroughly clean up the stripper and neutralize the residue w/ water followed by a light solvent (Check Interlux website: yachtpaint.com). 6. Rebed the sill with white, marine silicone or polysulfide. You'll need at least two 10-oz. tubes for a caulking gun. 7. Gently place the skylight back in the sill, and turn the screws until they're just threaded. Do not overtighten! 8. Go home. You don't want to tighten the skylight down until the sealant sets. What you've just done is built a solid, flexible gasket. 9. Mask the topsides and skylight, and fill any voids that are evident from the top, smoothing the surface as you go. You'll need to work quickly. I use a cup of water with a little dish-washing soap to dampen my finger for a smooth finish. Get the masking tape off before the sealant sets. 10. Check the Nov./Dec. 2004 edition of Good Old Boat Magazine, page 14, for a great article on sealants and adhesives. Website address attached.
John Nantz
I don't understand these bumps on. Can you please explian them in more detail? Thanks Droop!
I don't understand these bumps on. Can you please explian them in more detail? Thanks Droop!
Bump on Purpose
The purpose of the bump ons, as I understand it, is to allow the plexiglass to "slide" with expansion and contraction on it's coachroof support. I don't know for a fact that this is the reason but I suspect it is. Hunter specifies bump ons be used (they come on a piece of plastic coated paper and you peel them off and stick them on - they have self adhesive backing). The other thing the bump ons do is make it so the top surface of the plexiglass is flush with the coachroof but I don't think this is the reason for them. The x.5 series of Hunters used a smoke plexiglass where as the previous Legend series used a transluscent Lexan. The Lexan design "system" in my opinion was flawed and hence the reason so many of them leaked. The flaw was in not understanding how the fiberglass & wood coachroof/Lexan skylight/sealant sytem was supposed to work and providing accordingly. By the x.5 series it's my guess that Hunter knew they had a problem and attempted a new approach to fix it and the bump ons were a part of the new system. There seems to be fewer leak problems with the x.5 series than with the earlier Legend series. The Northwest Dow tech rep that came out and looked at my boat several years ago said that the sealant is supposed to act like a rubber band and not like glue. The sealant is supposed to stretch and contract hence the reason for not "bedding" the plexiglass and also the reason for using backer rod to prevent the sealant from oozing down and under the plexiglass. More trivia: One of the main leak points I've found are the screw holes. Since there are a lot of screws per skylight this means lots of opportunities for leaks. If the sealant is properly applied you don't even need screws because the sealant will hold the plexiglass down by itself. What I did initially was enlarge the screw holes to allow for better sealing and then the next thing, after a few of the screw holes still leaked (you can only enlarge the holes just so much), was take the screws out and plug the holes with sealant. This was several years ago and so far so good - no leaks. Another little detail. My coachroof has a slight curve to it so I've got about two screws per skylight still remaining because the Lexan (in my case) doesn't bend so the two screws are enough to maintain the shape needed. Kind of a long answer for a short question but I hope this helps.
The purpose of the bump ons, as I understand it, is to allow the plexiglass to "slide" with expansion and contraction on it's coachroof support. I don't know for a fact that this is the reason but I suspect it is. Hunter specifies bump ons be used (they come on a piece of plastic coated paper and you peel them off and stick them on - they have self adhesive backing). The other thing the bump ons do is make it so the top surface of the plexiglass is flush with the coachroof but I don't think this is the reason for them. The x.5 series of Hunters used a smoke plexiglass where as the previous Legend series used a transluscent Lexan. The Lexan design "system" in my opinion was flawed and hence the reason so many of them leaked. The flaw was in not understanding how the fiberglass & wood coachroof/Lexan skylight/sealant sytem was supposed to work and providing accordingly. By the x.5 series it's my guess that Hunter knew they had a problem and attempted a new approach to fix it and the bump ons were a part of the new system. There seems to be fewer leak problems with the x.5 series than with the earlier Legend series. The Northwest Dow tech rep that came out and looked at my boat several years ago said that the sealant is supposed to act like a rubber band and not like glue. The sealant is supposed to stretch and contract hence the reason for not "bedding" the plexiglass and also the reason for using backer rod to prevent the sealant from oozing down and under the plexiglass. More trivia: One of the main leak points I've found are the screw holes. Since there are a lot of screws per skylight this means lots of opportunities for leaks. If the sealant is properly applied you don't even need screws because the sealant will hold the plexiglass down by itself. What I did initially was enlarge the screw holes to allow for better sealing and then the next thing, after a few of the screw holes still leaked (you can only enlarge the holes just so much), was take the screws out and plug the holes with sealant. This was several years ago and so far so good - no leaks. Another little detail. My coachroof has a slight curve to it so I've got about two screws per skylight still remaining because the Lexan (in my case) doesn't bend so the two screws are enough to maintain the shape needed. Kind of a long answer for a short question but I hope this helps.
Don't removed the screws...
The sealant may hold in normal conditions, but you don't want to trust the sealant to hold when you/next owner end up in extremely bad conditions. If the skylight got knocked off by a heavy and powerful wave, it would be nearly impossible to stop the boat from sinking. I surf and know the power of waves. Just yesterday I was surfing the waves we got from the hurricane (16'). I got dumped on by two, both of which caught me by surprise. The first one almost finished me. I was going head over end about 10 times and headed for the rocks without much control underwater and before it hit I saw it just in time to grab and hold onto my board with all my strength...didn't matter. So if a 16' wave can knock me off my board when I'm laying flat and holding on with all my might (and I'm no weakling either), just think what it can do with that sealant.
The sealant may hold in normal conditions, but you don't want to trust the sealant to hold when you/next owner end up in extremely bad conditions. If the skylight got knocked off by a heavy and powerful wave, it would be nearly impossible to stop the boat from sinking. I surf and know the power of waves. Just yesterday I was surfing the waves we got from the hurricane (16'). I got dumped on by two, both of which caught me by surprise. The first one almost finished me. I was going head over end about 10 times and headed for the rocks without much control underwater and before it hit I saw it just in time to grab and hold onto my board with all my strength...didn't matter. So if a 16' wave can knock me off my board when I'm laying flat and holding on with all my might (and I'm no weakling either), just think what it can do with that sealant.
The Plexiglass Will Break First
Franklin - unless you've replaced a skylight you'd be really surprised how difficult it is to remove one without breaking it. It is REALLY hard. Besides, a wave or wall of water would have to "pull" on the skylight to cause it to come off. Pressure on the outside won't mattter because the Plexiglass or Lexan sits in a recessed on the deck so it's not going anywhere unless it actually breaks. This is the same sealant that is used to hold in those large windows in skyscrapers without clips or any other sort of metal fastner and the stuff does a really good job holding plexiglass too. What is interesting is that the cured sealant can be easily cut but don't confuse that with pulling loose. It is also really difficult to remove the old sealant and the best way is to use a sharp object and essentially cut or scrape it off. Bottom line, properly installed the plexiglass or Lexan will break before the sealant gives.
Franklin - unless you've replaced a skylight you'd be really surprised how difficult it is to remove one without breaking it. It is REALLY hard. Besides, a wave or wall of water would have to "pull" on the skylight to cause it to come off. Pressure on the outside won't mattter because the Plexiglass or Lexan sits in a recessed on the deck so it's not going anywhere unless it actually breaks. This is the same sealant that is used to hold in those large windows in skyscrapers without clips or any other sort of metal fastner and the stuff does a really good job holding plexiglass too. What is interesting is that the cured sealant can be easily cut but don't confuse that with pulling loose. It is also really difficult to remove the old sealant and the best way is to use a sharp object and essentially cut or scrape it off. Bottom line, properly installed the plexiglass or Lexan will break before the sealant gives.
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