sealing of deck fittings.

[Killick69]

Perhaps you are all aware of the article on sailnet forum regarding use of butyl mastic on a roll, used to seal deck fittings. If you have not seen the article (well written with photos), suggest you have a look. I think I typed in butyl mastic. The author is adamant that one must use the correct product (gray). Black will also cause staining. There is also a link to the mastic the author uses (only available in USA). Does anyone know of a similair product that is available locally? Points I took onboard are firstly to chamer the holes, secondly the difficulty of fully removing silicone (so avoid silicone if possible)and thirdly the long shelf-life of butyl mastic.
Important not to confuse the mastic on a roll with butyl tape. Also important not to seal from below deck (traps moisture (bad for S/S and makes finding leak more difficult, if there is one. Night Cap is pretty dry except for cockpit hatch leaking (no seal on it) and small leaks on forward hatch. Will attend to these shortly and later will need to replace safety lines and refit staunchions (Shaun, please let me know what you think). So thoughts on butyl mastic welcome and any suggestions on safety lines also very welcome.

[storm petrel]

I have always found Sikkaflex to be adequate for sealing deck fittings. Cheers, Mark

[Shaun]

Gday John,
Many thanks for alerting us to that article on Butyl Tape, here is the link
http://www.sailnet.com/forums/gear-main ... -tape.html

Its quite timely as I have a few cleats & grab rails to install shortly, & this butyl stuff sounds great! (if it doesnt need too much building up in thickness, to get a seal, thick butyl is a bit of a dust collector), buying the sikaflex tubes(291) make my eyes water when I get to the check-out , & you might as well call it a one job tube, or two job if your lucky, plus the working time is quite limited if your doing a tricky job, as on my fore hatch repair recently, the 291 was starting to go off. Plus its very messy .
If you find a source of the proper Butyl tape let us know, & i'll have a look around too.
Ive already rebedded half my staunchions on Blue Moon with Sika291, I'll try to do the remaining ones with the Butyl & see what the difference is.
Just re-bed your staunchions only if their leaking.
cheers
Shaun

[bornfreee]

Hi Killick those life lines are only a few years old up to you if you think they need replacing

[storm petrel]

Have you tried leaving the sikkaflex in the freezer?

[Shaun]

Does freezing it prevent it going off? would it affect the product?

Just tried this butyl method while installing a new cleat for a drogue, its certainly cheaper & not messy at all, but im not converted instantly (it just seems too easy), maybe i didnt use the correct butyl tape, i used some butyl tape that i found in the shed, its what is used to bed down stainless steel sinks. There was still a tiny bit of movement in the cleat when id finished the job (I had to swing off it to move it tho'), you dont get any movement with sika291, but it will now be easy to remove if I need to. will see how it goes as far as being watertight.

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