Mast boot sealant?

[High Current]

Going to launch + step the mast for the first time on Wednesday.

I think I understand the process but can't figure out what sealant to use for the mast boot.  The Catalina manual just says "caulk."   I've seen mention of silicone on the forums, but after removing a bunch from my leaking chainplates I don't want the stuff anywhere near my boat...

Any suggestions would be greatly appreciated.

[Noah]

I would recommend Sikaflex 291 for that kind of sealing job.

[High Current]

Thank you!  That looks good.

[Phil Spicer]

 Silicon tape has on adhesive, just stretch and it will stick to itself and the mast. On mess to clean when it is removed. You can run it around the mast joint 2 or 3 times for a good seal. Found a 4" wide silicone mast seal tape this week. Once around and done. Will post the name of the tape when I get to the boat this afternoon.
Years age I found "Rescue Tape" at the Annapolis boat show. Used that for years. ( my marina pulls all masts because of a wire across the yard. ) Silicone tape became my go to mast seal.

[Ron Hill]

High : If you look in the Mainsheet tech notes you find an article I wrote on removing and reinstalling that mast. Biggest thing to remember is to slide in that "mast tie down piece" in the sail track!! 

Also make yourself a sunbrella cover for your over the mast boot (to keep it out of the hot sun!!) Another Mainsheet tech note article!!

A few thoughts

[Phil Spicer]

 The silicone tape I found is "Tommy tape mast boot wrap."  Should only take one time around the mast to get a good seal. Will know tomorrow when we splash.
    Phil

[Jim Hardesty]

One of the sailors in my club uses only shrink wrap tape.  No mast boot. Takes mast down every year and new shrink wrap tape.  Works for him.
Jim

[High Current]

Thanks again for the help everyone!

I love rescue tape but didn't see the post in time.  If that works it seems like a nice, mess-free solution.  But I've had trouble making waterproof seals with it in the past.  Ended up with a tube of Sikaflex.  And I'll definitely look into making a cover.

Launch was Wednesday, but when we went to step the mast there was 1/2" of water in what had been a bone-dry bilge the day before.  Uh-oh.  Found a steady trickle coming around the thru-hull for the speed transducer.  So I got to do some below-the-waterline sealing too!  Happy to report that (after much work) the 2nd attempt yesterday was successful.

[Baysider]

The mast boot tape approach sounds too good to be true.  I have a boot that's about 6" high, aging, and it leaks. Do I understand correctly that the tape simply gets (stretch) wrapped around the mast and the mast collar? No more boot? How long does it last? Thanks!

[Phil Spicer]

  Bayside, I use the factory boot and large hose clamps after setting the wedges in place. Then run the silicone tape
over the boot to seal everything. One inch tape worked for years, going around two times at the top of the boot with about a half inch overlap. Then I found 2" tape and now 4". Things just keep getting easier.
  As for how long the tape will last, I don't know, my mast comes down every year so the tape is removed.
  Don't forget to PLUG the SAIL SLOT !
    Just my view, my solution
         Phil

[Baysider]

Thanks Phil.

[Baysider]

Phill:
When you refer to the factory boot are you referring to the original boot or a replacement from Catalina?  Do you un-step the mast or use a boot that gets cut and wrapped? Thanks!

[Phil Spicer]

 Bayside, after 20 years or so the factory mast boot was looking a little bad so I got a new one. Think it came from CD
but was a lot less than price today. Mast comes down every year. I cut the silicone tape, undo the large hose clamps on the boot and slide the boot up the mast to get to the wedges. Then the mast is pulled. I have used 1",2" and 4" wide tape. All work well to seal the boot, wider is just a little less work. The boot does not get cut, just the tape. The nice part of the tape is no sticky adhesive to clean off.
     Just how I seal the boot.
         Phil

[Stu Jackson]

I've seen mention of silicone on the forums, but after removing a bunch from my leaking chainplates I don't want the stuff anywhere near my boat...

Any suggestions would be greatly appreciated.

Phil,

"...anywhere near my boat..." is a wise approach re: silicone, EXCEPT it is the ONLY material recommended for the Beckson ports most likely in your cockpit.  Otherwise, you're right because silicone "caulk" for chainplates is the wrong material.  what should be used is butyl tape, specifically Bed It with Butyl from Maine Sail ONLY - not all butyl tape is made the same.  The 101 Topics has my chainplate rebedding article.

As for the mast boot, Noah's right.  And the other ideas are excellent, too.  I took an idea I found here years ago that worked: stuffed a bunch of large rope around the mast into the partners and  siliconed around the edges.  It worked, too, in addition to these ideas.  I think the silicone tape makes the best one.  Rescue tape could work maybe even better.

[Phil Spicer]

  Stu, as I understand it, Rescue tape is silicone tape. That is what I used first. Then I looked for wider tape so the top of the boot could be sealed with only one wrap instead of 2 or 3 times around. As for silicone calk, not on our boat !