Butyl Tape = Rope Caulk?

[Tanley]

Was at the marina and chatted up a guy who was re-bedding his gate stanchion. I asked him where he got the butyl tape and he said he was using rope caulk from Home Depot. The stuff felt tacky, but aren't they two different things? I thought rope caulk hardens over time.

It was a different brand, but basically this stuff

Ace Pliable Rope Caulk (219/ACE)

[davester]

I don't think its the same... that looks like the brand moretite (moretight? sp?) which I used in one area (it's working fine so far). I recently picked up some real butyl tape at an rv store and it looks and feels different... the moretite, while pliant and tacky, is almost crumbly by comparison... if you pull it apart, it breaks sooner.

I would guess that moretite, or the stuff pictured, won't harden too fast if at all, since its sold in a cardboard box without any airtight container, but only time will tell. Still, after handling the butyl tape - I think its worth getting the real thing.
Dave

[US27inKS]

I believe most rope caulk products are butyl based. The compound is slightly different than butyl tape, but it should work as good. Butyl products range from really gooey to pool liners, so I wouldn't be put off by a slightly different consistency. The purpose of using a butyl product in sealing boat hardware is that it shouldn't harden. I've used rope caulk like this for automotive work for decades. The boxes are never sealed, and I can never remember any rope caulk drying or becoming hard.

[Maine Sail]

Rope caulk is NOT butyl tape!!! I would not use it for bedding....

[primerate84]

I agree with Maine, use the butyl tape for re-bedding the stanchions. I used it on my windows and it works great.

[US27inKS]

Originally Posted by Maine Sail

Rope caulk is NOT butyl tape!!! I would not use it for bedding....

I trust your experience on this. My mistake. Rope caulk sure seems a lot like a butyl product. I know the consistency is a bit different, but you can get butyl rubber pool liners that are nothing like butyl tape.

Any idea what rope caulk is if not butyl??

[sailingdog]

I wouldn't use rope caulk. Get the real stuff, it is only $7 a roll or so...

I'd point out that there are a lot of butyl rubber based products, and most of them are NOT SUITABLE FOR BEDDING HARDWARE. Just because it has butyl in the name does not indicate that it is a good choice.

[pdqaltair]

Originally Posted by sailingdog

I wouldn't use rope caulk. Get the real stuff, it is only $7 a roll or so...

I'd point out that there are a lot of butyl rubber based products, and most of them are NOT SUITABLE FOR BEDDING HARDWARE. Just because it has butyl in the name does not indicate that it is a good choice.

... which probablty explains some portion of the occational poor results that are reported.

Sort of like 100% silicone caulk vs. "silicone" latex caulk. Very different.

[Tanley]

Back down this weekend and he's re-bedding more stanchions so I ask to watch since I've never seen it done before. Really nice guy, and happy to have some company. Turns out he did these 5 years ago and is starting to get leaks below deck. He used the rope caulk last time around too.

I've never re-bed anything, just have Maine Sails' write up as a reference. But when he pulled off the old stanchion, there was no stretch at all. I didn't touch it, but it looked almost brittle when he pulled the base off. Kind of like the rope caulking I've seen used in home windows after several years - hardens and shrinks a bit with a little cracking. Definitely nothing like what is in Maine Sails' tutorial.

The worse part is that it isn't any cheaper than butyl tape. I can't understand why he wouldn't just use butyl tape?

BTW, he thought they were leaking again because he hadn't counter sunk the holes. Which is a valid point, but after seeing the condition of the rope caulk, I would've thought he'd change the bedding compound.

[Sabreman]

I looked at about 10 local hardware & big box stores and couldn't find any real butyl tape. Bought it on eBay. Lots of availability.