What Caulk to Use?

[psneeld]

Originally Posted by Larry M

I don't have enough guts or believe Dolfinte should be used on everything. I will still use a polyurethane type caulk maybe some butyl tape where I want some adhesion and a sealant.

i think bedding compounds are great for wood...but where thing constantly work...an adhesive caulk is usually preferred. I wouldn't worry about using something like 5200 on things like railings and cleats (rarely removed) that are metal...you can always add a little heat to help break the bond when you do have to remove them.

I forget which naval architect recommends it...but one of the popular ones (read prolific writer too), but he recommends all deck hardware to be epoxied down with the same thought in mind...spreading the load to more than just the fasteners and heat will release the epoxy when the time comes.

I'm redoing my windows and I think I'll do the butyl tape route...I think it will be the neatest...

[RT Firefly]

Greetings,
Mr. Larry M. Your fasteners SHOULD be the primary means of affixing anything to your boat as Mr. FF states. The bedding material is only there to prevent water ingress and NOT IMHO to add strength in holding stanchions, ports, mast base etc. If your fasteners fail, I wouldn't place much faith in ANY adhesive being able to do the job of intact fasteners. For sealing mating edges of house and deck or seaming teak decks, for example, YES a good caulk is the way to go but as I stated earlier, I'll NEVER use caulk for bedding EVER!
That being said, I have only recently become aware of butyl tape which I will consider using in future specific applications.

[psneeld]

Originally Posted by RT Firefly

Greetings,
Mr. Larry M. Your fasteners SHOULD be the primary means of affixing anything to your boat as Mr. FF states. The bedding material is only there to prevent water ingress and NOT IMHO to add strength in holding stanchions, ports, mast base etc. If your fasteners fail, I wouldn't place much faith in ANY adhesive being able to do the job of intact fasteners. For sealing mating edges of house and deck or seaming teak decks, for example, YES a good caulk is the way to go but as I stated earlier, I'll NEVER use caulk for bedding EVER!
That being said, I have only recently become aware of butyl tape which I will consider using in future specific applications.

while I agee the fasteners should have the strength...if they work loose...you are adding a dynamic in there that weakens the system.

[RT Firefly]

Greetings,
Mr. psneeld. If you're saying that Dolphinite is the dynamic that weakens the system, that's exactly my point. If the fasteners work loose, tighten them up. I do NOT feel adhesive/caulk adds to the overall strength that justifies it's use. As Mr. FF correctly pointed out, pretty well everything will fail after a time and have to be renewed. As I mentioned in a previous thread, I wished to save and re-use teak moldings around a hatch and had the devil of a time breaking the failed bond of previously applied caulk/adhesive and removing the crap that had adhered to the moldings prior to re-bedding with Dolphinite. My repair currently does not leak as it did before and I feel confident if it ever does, and I'm sure it will, I'll be able to easily remove and rebed said moldings.

[psneeld]

Originally Posted by RT Firefly

Greetings,
Mr. psneeld. If you're saying that Dolphinite is the dynamic that weakens the system, that's exactly my point. If the fasteners work loose, tighten them up. I do NOT feel adhesive/caulk adds to the overall strength that justifies it's use. As Mr. FF correctly pointed out, pretty well everything will fail after a time and have to be renewed. As I mentioned in a previous thread, I wished to save and re-use teak moldings around a hatch and had the devil of a time breaking the failed bond of previously applied caulk/adhesive and removing the crap that had adhered to the moldings prior to re-bedding with Dolphinite. My repair currently does not leak as it did before and I feel confident if it ever does, and I'm sure it will, I'll be able to easily remove and rebed said moldings.

No Dolphinite doesn't weaken anything...it just doesn't hold the components as securely as an adhesive...so things work loose and loose things have higher loads on them.

Even West Systems epoxy suggests and shows how to bed marine hardware with epoxy....they have been around the block on this one.

I would use a soft bedding compound for small wooden trim around a hatch also...but for railings, mast/davit bases, and all other constant cycle and high load joints I would use an adhesive sealant as long as the hardware was metal....so I could use heat to help soften the bond when the time came to redo/repair.

I know both sides of the coin...so I use what I think will last the longest and do the best job...but I'm sure we all have experiences that have led us to our opinions because the manufacturer's claims have fallen short of our expectations.

Plus...to tighten some hardware up...getting a tool on the backside requires that trained boa constrictor and I can't find him in the yellow pages anymore!!

[FF]

For folks working on their boat , one simple solution to very high stress fittings is quite simple.

Raise the sealing surface so standing or modest water will not even see the sealing.

We use GRP from a scrap boat or part removed , sometimes 1/2 thick can be found.

A removed transom may be REALLY! nice and thick.

Simply cut a pad larger than the fitting and epoxy (thickined) the pad to the deck on the outside.

Drill up from under to relocate the fastening holes from below.

Now with the item raised 1/2 or 1 inch from the deck surface , your choice of sealing goop has very little to do, till the standing water is over that 1/2 or 1 inch.

Cheap, simple and works every time!

One caution is really modern fittings stuck in with calking tape should be re bedded just with the tape.

Its cheap and a snap to remove , and really fast to R&R.

FF

[HopCar]

I'm with psneeld on the issue of 5200. I just installed a couple of rod holders and bedded them in 5200. It is very unlikely that I'll ever have to remove them but if I do, I'll just warm them with a heat gun or propane torch and they'll pop right off. I don't use 5200 for added structural strength, I use it because it is superior at keeping out water for long periods of time.

All joints on a boat move to some extent. My rod holders will expand slightly faster than the fiberglass deck as the sun warms them. The 5200 will adhere to both the deck and metal but will flex enough to with stand the expansion and contraction of the joint.

I do use 5200 as an adhesive in place of fasteners as well. My teak boat hook holders are glued to the fiberglass with 5200. They've been there for many years now with no screws.

[CPseudonym]

I hear a lot of folks talking about sealing leaks. Was taught re-bedding should be a preventative task. If the joint is leaking it sounds as though you are at least 2 seasons behind on maintenance.

If re-bedding was handled regularly to begin with there would be fewer soft decks and dry rot to deal with. I'll stick with butyl tape done skillfully, with care and look further into this Dolphinite.

Adhesive has no place on my boat for anything above the waterline that may need removal. JMHO/YMMV

[psneeld]

Originally Posted by CPseudonym

I hear a lot of folks talking about sealing leaks. Was taught re-bedding should be a preventative task. If the joint is leaking it sounds as though you are at least 2 seasons behind on maintenance.

If re-bedding was handled regularly to begin with there would be fewer soft decks and dry rot to deal with. I'll stick with butyl tape done skillfully, with care and look further into this Dolphinite.

Adhesive has no place on my boat for anything above the waterline that may need removal. JMHO/YMMV

Why would anything below the waterline require adhesive??? Or is there no place for it there either????

[stevensibs]

I am a big fan of Butyl rubber, both in tape form and in a tube. Silverton used it on my convertible 28 years ago, and when I removed all the deck hardware and bow rails to Awlgrip, the stuff was still soft and pliable, so I chose butyl to re-bed everything. You must not tighten down the hardware too much for a few days, to give the butyl time to set. Then after, you can re-tighten. It comes in grey and black 1/2" tape, 100' rolls, and tubes for caulking guns.

[CPseudonym]

Originally Posted by psneeld

Why would anything below the waterline require adhesive??? Or is there no place for it there either????

The only thing that comes to mind off the top of my head would be a through hull transducer. As I have no below waterline through hulls on my current boat I've not concerned myself with that part of the topic enough to offer anything of value to the discussion.

[rwidman]

My gripe - The stuff has a short shelf life after it's opened. Sometimes a day or two. There may not be a good solution for that, but why can't we buy it in 1 ounce "single use" packets?

I am installing six small fender cleats and I'll throw away $6 worth of a $7 tube of adhesive sealant.

Worse, I won't throw it away, I'll keep it but it will be useless when I need it next and I'll have to make a special trip for more.

[psneeld]

Originally Posted by CPseudonym

The only thing that comes to mind off the top of my head would be a through hull transducer. As I have no below waterline through hulls on my current boat I've not concerned myself with that part of the topic enough to offer anything of value to the discussion.

There a much bigger chance of changing out a ducer long before having to remove much of your deck hardware...so I guess I'm missing your emphasis on adhesives.

[HopCar]

Ron,
5200 is available in 1 oz. tubes. You should be able to find at any good marine store.

[CPseudonym]

Originally Posted by psneeld

There a much bigger chance of changing out a ducer long before having to remove much of your deck hardware...so I guess I'm missing your emphasis on adhesives.

Sorry, perhaps poor wording on my part.

The purpose of bedding material is to provide a water tight seal, not to somehow strengthen the attachment. Hardware is to provide a strong attachment, not something out of a tube.

Researching while preparing to re-bed my boat I've determined it's the adhesive nature of caulks and silicone's that turn folks away from the project. Folks hate the chore because of the problems associated with ripping and tearing apart of wood and painted surfaces. If folks hate a chore, they tend not to do it very often. When it's deferred until leaks appear, we wind up buying used boats with soft decks, cabins, etc...

I just re-bedded a sailboat that's spent it's entire life uncovered in the California sun. I had no trouble removing anything without damage or fuss. Clean up and prep was a snap. Butyl was the factory choice that lasted nearly leak free since 1977 and I suspect the newly bedded hardware will last just as long if allowed. If a product like caulks or silicone had been used by the factory the re-bed project would have been a nightmare IMO.

I learned simple things like chamfering holes and not over tightening hardware does more to preserve fiberglass both leak and spiderweb crack free than almost anything else. Loose hardware should be re-bedded, not just snugged down on old sealant. And that is what most people will do, especially if re-bedding is such a pain in the rear.

My project was a breeze and if I feel compelled, it's something I'd gladly do again in 5 years or less(pretty sure I won't). The next owner of my boat will not be cussing the PO for using a poor material either. I'd like to read more on Dolphinite as it seems to share many of Butyl tapes qualities.

Does that better explain what I consider adhesive?

[FF]

"It is very unlikely that I'll ever have to remove them but if I do, I'll just warm them with a heat gun or propane torch and they'll pop right off."

Oak has a burn rate of 100.

Builders Cheap GRP has a burn rate of 500, it burns 5 times better!

That's why the USCG requires FR (fire retardant) resin on commercial boats that carry over 6 ..

The burn rate of FR resin is 100.

A propane torch is a dangerous tool on a plastic boat.

[rwidman]

Originally Posted by HopCar

Ron,
5200 is available in 1 oz. tubes. You should be able to find at any good marine store.

Yes, but that local "good marine store" charges $11.00 for the one OZ tube and Walmart or the home center harges $7.00 for the 3 OZ tube!

[psneeld]

Originally Posted by FF

"It is very unlikely that I'll ever have to remove them but if I do, I'll just warm them with a heat gun or propane torch and they'll pop right off."

Oak has a burn rate of 100.

Builders Cheap GRP has a burn rate of 500, it burns 5 times better!

That's why the USCG requires FR (fire retardant) resin on commercial boats that carry over 6 ..

The burn rate of FR resin is 100.

A propane torch is a dangerous tool on a plastic boat.

Gimme a break...we are not all idiots out here....and glass doesn't just burst into flame...yes once going it does really go though.

But using a propane torch around fiberglass for warming deck hardware to realease an adesive joint isn't like welding or removing paint/varnish...sheeesh...

If a boater is totally inept, a heat gun is recommended then...

[rwidman]

Lots of "experts" here, the problem is, they seem to be 180 degrees apart on this so the rest of us leave as confused as when we walked in the door.

I would say the wise thing to do is to read the packaging of each type of product and decide, based on that information, which product is most suited for the task at hand.

[rwidman]

If a boater is totally inept, a heat gun is recommended then...

Heat gun user here. I used one yesterday to remove the adhesive where I cut back some non-skid foot pads.

A torch might be appropriate for removing a stuck prop, but it's apt to discolor cleats and such that you might want to re-use.