Bed-it Butyl Tape OK for screwed in fasteners?

[Brian S]

I've use Maine Sail's butyl tape for bolted on fittings.

But now I have a bunch of screwed on fittings like bullseye fairleads, cam cleats, and wood trim. I have the holes in the glass countersunk. And I'm debating whether it would be better to put butyl on the screws and then screw the fittings down, or put Life Caulk on them. When I put on through bolted items, I can hold the bolt from spinning, so I know the butyl is mooshing in around the screw. But I'm concerned about the twisting of a screw pulling the butyl away from the screw and allowing leaks. I'm thinking a more liquid caulk like Life Caulk would be more tolerant of the spinning screw, especially with countersunk "reservoir" to hold material against the screw, and that once in place, the caulk would "flow" back around the fastener.

What say you all?

 

[dscribner]

Are you putting it under the head or between the pieces being screwed together? The best way is to countersink the fiberglass a bit. When the tape goes on and gets compressed, it is forced into the hole and seals the screw shank, not under the head. Even if the screw is turning, the butyl will ooze back into place. Remember, it's non-curring.

 

[Brian S]

Thanks, D-scrib (that's your new hip-hop name, now )

I will be putting a cone of tape around the fastener, under the fitting. So the fitting (or wood trim piece) will mush down on top of the glass, over the countersunk portion, goobing around the fastener.

I anticipate it will be far easier to remove the butyl tape next time I need to, say, varnish the splash boards. The previous owner didn't do a very good job of varnishing, and then he glued stuff down with clear silicone. To remove the splash boards, I basically had to shove a thin metal putty knife under them to cut the silicone. And, of course, the wood was contaminated under the inadequate amount of varnish, so fish eyes were legion. AUGH!!!!

 

[Anonymous 121765]

Brian, er, D-scrib,

There are many different thru deck fittings on a sailboat.

The questions you need ask yourself are, what is & what is not load bearing first.
On my boat, any fitting that has a load on it, I DO NOT use wood or sheet metal screws,

Depending on the amount of load bearing properties, I will either use thru bolts, Nylock nuts, and/or maybe an oversize washer or, when necessary, a backing plate. Now I know my fitting is properly supported & less to failure.

Each fitting is different, it's for you to decide what is properly adequate.

CR

 

[Brian S]

Sure, Captnron, this is true. I'm replacing existing hardware on a Force 5 in this instance. Pretty much everything is screwed into plywood backers in the deck and cockpit. Boat's in good shape, but I figure if I seal it up well, it'll stay in good shape longer! I have had to replace the bolts in the rudder bracket, which are a known weak point with original spec #10 bolts, which have now been drilled out and through bolted with 1/4". And properly bedded with butyl. While I was at it, I stripped all the hardware off since the wood was already removed, making it easier to polish. Since it's all off, I might as well seal it up!

 

[Maine Sail]

Yes screws can be sealed with Bed-It Tape. Just make the cones a bit longer and drive it in slowly...

 

[mm2347]

Brian: Ive used the butyl tape on screws and removed a few years later to find it works well. It helps to warm everything up carefully with a heat gun. The only prob is that the butyl will ozze out the first few time in the hot sun but it is easy to trim off. Its the only stuff that Ive used that will let me take it apart but has never failed. Yes I have used 5200 and it did not leak. But it was a mess when I took it apart to refinish the boards.

 

[Brian S]

Thanks, MaineSail and MM. I'm going to go with the Butyl, which just seems easier all around. I'm glad to hear it will work ok for what I've got! Sure as hell beats silicone!