This thread has been most informative. I did not find any of the comments to cross over the line vis taking a personal slant.
FWIW - At several recent boat shows, I asked manufacturers' reps about the material they core with and whether they use any technique to seal the holes cut for hardware installation. It surprised me how many of the reps had no idea what core material their boats use. Fewer still knew what I was talking about regarding sealing the holes. The few that did told me that they did not do anything more than properly bed the hardware. And that this is the industry standard. One recommended that a prudent owner WOULD remove all the fittings, seal the holes with epoxy and rebed the fittings.
Joel Bondy
s/v Pokey II
'73 Ty #549
Bayside, NY
Installing Deck Hardware
Moderator: Jim Walsh
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John R.
Re: Installing Deck Hardware
Joe, you are right that much standard equipment hardware (especially high load hardware)will be mounted through reinforced coring that was installed during original layup. With that said it is not at all unusual that various hardware components will be installed through a non-reinforced area of the deck. It's very normal to find solid layup or a glass chop filler used in a vulnerable location like a hatch opening. That area of fill or solid layup is not large however. It would be easily conceivable to cut a larger opening and accidently go beyond the reinforced perimeter. Luckily you didn't run into that problem or you would have had a little extra work to do.
That hollow area you discovered between the liner and cabin top is not real common but like you discovered it does happen. Those situations tend to arise more on smaller boats or inexpensive boats. Based on your info you wouldn't necessarily need to cut away the liner but you would have to fill the void as much as possible. It would not be easy to do this since all you have available are the bolt holes for access unless you utilize the drill fill technique but even at that depending on the size of the void you may have to take more radical steps to gain better access. A situation like this is a case by case basis. You have to evaluate every possibility to render a sensible cure. For example if you did a drill and fill how much filling would it require? Is it a bottomless pit (figure of speech)? Where is the core? A correction to a problem like you've outlined takes some careful thinking and planning. There isn't a simple solution. It takes some ingenuity. Understanding what you are up against and what remedies are available goes a long way in effecting a reasonable cure to the problem. A good thorough understanding of various materials and how to use them is critical.
As you noted getting fill in there is the challenge. You can either inject it in stages using a flexible (and cleanable) extension on a large syringe or caulk dispenser; obviously this limits you to only thickened fill not a substantial fiber reinforced fill. You can purchase empty caulk cylinders that can be loaded with your chosen filler from just about all decent marine suppliers or industrial supply houses. You can use it in a mechanical or pneumatic dispenser. Aside from that and being at a disadvantage of not seeing the particular situation you would pretty much be relenquished to doing some surgery. If you do it with the injection method be absolutely certain you only do it in stages. If you inject too much at one time the mix will become very hot when it kicks and could damage surrounding materials, namely the liner or cabin top.
Make sure to use backing blocks.
Hope this helps a little.
John, thanks for your comments. I have been under the (perhaps erroneous) impression that the pad eyes and upright blocks on our 30 were mounted in an area that was "solid", not cored. Also, the winches that were factory installed. I installed an aft cabin hatch in our previous 28 and used the larger size which required enlarging the existing hole. The entire area I cut into was solid; perhaps a mixture of resin and chopped glass, or some other filler. I have also placed blocks, etc. on a previous 22 and found a space between the liner and the coach roof; no filler and no coring. In cases like that I would assume you'd need to cut away the liner, or provide some fill to make the structure a single layer. Any thoughts? Your experience having already done some of this on a 30 would be helpful.
That hollow area you discovered between the liner and cabin top is not real common but like you discovered it does happen. Those situations tend to arise more on smaller boats or inexpensive boats. Based on your info you wouldn't necessarily need to cut away the liner but you would have to fill the void as much as possible. It would not be easy to do this since all you have available are the bolt holes for access unless you utilize the drill fill technique but even at that depending on the size of the void you may have to take more radical steps to gain better access. A situation like this is a case by case basis. You have to evaluate every possibility to render a sensible cure. For example if you did a drill and fill how much filling would it require? Is it a bottomless pit (figure of speech)? Where is the core? A correction to a problem like you've outlined takes some careful thinking and planning. There isn't a simple solution. It takes some ingenuity. Understanding what you are up against and what remedies are available goes a long way in effecting a reasonable cure to the problem. A good thorough understanding of various materials and how to use them is critical.
As you noted getting fill in there is the challenge. You can either inject it in stages using a flexible (and cleanable) extension on a large syringe or caulk dispenser; obviously this limits you to only thickened fill not a substantial fiber reinforced fill. You can purchase empty caulk cylinders that can be loaded with your chosen filler from just about all decent marine suppliers or industrial supply houses. You can use it in a mechanical or pneumatic dispenser. Aside from that and being at a disadvantage of not seeing the particular situation you would pretty much be relenquished to doing some surgery. If you do it with the injection method be absolutely certain you only do it in stages. If you inject too much at one time the mix will become very hot when it kicks and could damage surrounding materials, namely the liner or cabin top.
Make sure to use backing blocks.
Hope this helps a little.
John, thanks for your comments. I have been under the (perhaps erroneous) impression that the pad eyes and upright blocks on our 30 were mounted in an area that was "solid", not cored. Also, the winches that were factory installed. I installed an aft cabin hatch in our previous 28 and used the larger size which required enlarging the existing hole. The entire area I cut into was solid; perhaps a mixture of resin and chopped glass, or some other filler. I have also placed blocks, etc. on a previous 22 and found a space between the liner and the coach roof; no filler and no coring. In cases like that I would assume you'd need to cut away the liner, or provide some fill to make the structure a single layer. Any thoughts? Your experience having already done some of this on a 30 would be helpful.
Joe Sankey wrote: Joe Sankey
CD 30 Slow Dance
Magnolia Springs, ALJohn R. wrote: Well, I knew I stuck my foot in it the second I made that previous post, I was reluctant but I thought it important the board represent different ideas and opinions so I made a knowingly controversial one. I fully expected the feedback I received. I appreciate your questions and comments Warren and I'll do my best to express a reply to your request for answers regarding your questions.
But yes, you can get a good idea when it is time to rebed by looking for telltale signs of aged bedding. Look for a deteriorated edge to the visible caulking under a given piece of hardware. Dried out looking, broken edge, lifting are signs of aged bedding. Several years to about ten should be about average service life for common bedding such as polysulfide where it can be trusted and relied upon to maintain a good seal. In many cases you can get far more time if the caulking was applied properly from day one.Warren Kaplan wrote: John,
Interesting observation. I have a few questions (not arguments). As I read your remarks the main consideration was with adequate bedding. If bedded adequately there is no need for the technique. I would agree but have just two comments. 1) Bedding doesn't last forever and usually you find out about that when you discover a leak or the deck around the fitting is getting a little soft. Even if properly bedded orginally, and even if rebedded periodically, one cannot predict with any accuracy how "effective" that bedding will be and for how long.
At this point let me point out that there is not one piece of hardware on a Cape Dory that has been installed by the factory utilizing any kind of epoxy core technique to protect the decking core. It isn't necessary (with proper maintenance) or the builders would do it. Someone mentioned a stanchion base flexing and if thats the case the bases need to be reinstalled because they shouldn't move. The stanchion post may move in the base but the base itself should not. If it (the base) moves then you can expect some leaking eventually 9especially around the fasteners) or at the minimum some crevice corrosion of the stainless bolts from trapped moisture. A factory will normally never allow a boat to make it through final inspection with hardware that is not firmly secured without movement. Hardware is installed with only caulking and it is applied in a specific calculated manner. In essence it is applied very liberally creating much waste but assuring a leak proof installation. Particular attention is paid to fasteners.
2) The "drill and fill" technique, along with good bedding, is like a "belt and suspenders" approach, where if the belt (bedding) fails the suspenders (epoxy fill) will keep your pants up. But again, you are right, good bedding and good attention to the maintenance of that bedding would make the epoxy unnecessary.
Precisely....also the drill fill method can have the added insurance (like the suspender metaphor) if that is what a person wants to rely on. That is assuming of course that the drill fill method was done correctly. There is a time and place for that type of installation. I'm not saying it should never be done. It is not necessary on a Cape Dory in my opinion or in my experience. I would venture to say at this point that a new Robinhood will only have caulked hardware unless otherwise requested by a purchaser willing to pay for beyond the normal methods. I can not imagine Robinhood advising a buyer to go the drill fill route.
For those that are or have done the drill fill method on some hardware how are you going to retain the possible advantage of the drill fill if all the other hardware on the boat is installed only by traditional bedding methods? I simply can't imagine that anyone in their right mind would even entertain the idea of removing all the boats hardware to acheive a boat with 100 % drill fill hardware installation.
I think the drill fill is fine for those who are willing to go to the trouble and gain some peace of mind. I am only advocating the simple, effective, time tested and common method of hardware installation; used by manufacturers, boatyards, servicers and owners everywhere. Bedding alone is the tried and true method. Pick your poison as the saying goes.
Simply put, use backing plates which greatly spreads the loads over a broad surrounding area. Forget just washers, fender type or otherwise. Anything that is going to take loads must have a backing block. I have a deck mounted winch that handles the spinnaker halyard and the vang and the topping lift and it functions along with a multiple rope clutch assembly. These are mounted on the cabin top to starboard of the companionway. They have been there for at least ten years and have never leaked a drop, the deck shows no signs of stressing and the liner shows no signs either. The hardware is installed using .25" aluminum backing blocks. I have two winches on the port side of the companionway on the deck and they also have absolutely no problems and are mounted the same way. There is a deck organizer block, stand up turning blocks mounted in similar fashion. Two windlasses (talk about stress and loads) and they have no problems. I can make a considerable list of different hardware that I've installed and nothing has a leak except for two port holes! Now that is an area for discussion, how in the world would anyone do a drill fill technique on the tapping screws used to install portholes? Of course it could be done but it would be utterly ridiculous to do it. I think caulking being one year shy of 20 years old is damn good service life. Being that all other port holes are fine I imagine there will be a minimal amount of caulk behind the port hole trim when I remove them and that is where the problem lies. The installer is a big part of the equation when it comes to preventing leaks.Warren Kaplan wrote: My main concern, however, is with deck strength around a high load fitting like a winch or a cleat. You addressed that with high performance boats that might have light weight "flexible" decks. So the main question that I expect everyone would want to ask is..do you think a standard balsa cored deck, like a cabin top on a CD27, is sufficiently strong AS IS, to install a winch which will be subject to loads with just proper bedding, large fender washers and/or a backing plate? Do you think tightening up on the bolts and then subjecting the winch to tensile forces would not distort or otherwise weaken the balsa cored deck? Certain fittings that are primarily subjected to shearing forces (deck organizers and rope clutches) as opposed to tensile forces (winches, cleats and padeyes) might not need all that deck reinforcement but the ones subject to tensile forces, I would think, do. I'm interested in your take on this.
I hope these comments were of some help.
Warren Kaplan wrote: Thanks,
Warren Kaplan
Sine Qua Non
CD27
Oyster Bay Harbor, NY