The many forms of butyl tape/sealant

[cherod]

If you countersink the surface under the fitting the butyl is compressed around the screw as it beds down .

gets heavily disformed an even pushed out , in my experience

 

[Rappey]

All my cleats, chain plates bolted through deck, teak handrails on cabin roof and very long genoa tracks were bedded on some sort of butyl putty some 37 years ago and still not a single leak. It has hardened some though.

 

[cherod]

All my cleats, chain plates bolted through deck, teak handrails on cabin roof and very long genoa tracks were bedded on some sort of butyl putty some 37 years ago and still not a single leak. It has hardened some though.

yes, " bolted " ,, not screwed ?

 

[mrangry]

I just re-bedded my hatches onto the coachroof using butyl tape and they were screwed. They now dont leak....so far

 

[Rappey]

yes, " bolted " ,, not screwed

We both have our own opinions.
My following post was praising the virtues of butyl

 

[cherod]

ok , fine, i am glad to hear that , just me having the difficulty tho i have heard that before as well.