Butyl rubber to seal screws?

[George Da Porge]

I've read through Mainesail's primer on bedding gear with butyl. Am convinced that's a great way to go for many applications. One nice thing is that it seals right away since it has no cure time. But it is recommended to tighten the fasteners over a several day (or longer) period. Keeping that in mind, can butyl rubber be used in applications where the fasteners doesn't penetrate the hull or deck? For example, on our Catalina 30 some cabin-top hardware (deck organizers, winches, etc.) is anchored by nuts embedded in the core. If you tighten these bolts over a number of days won't the seal between the BR and the bolt be broken?

 

[woodster]

I've read through Mainesail's primer on bedding gear with butyl. Am convinced that's a great way to go for many applications. One nice thing is that it seals right away since it has no cure time. But it is recommended to tighten the fasteners over a several day (or longer) period. Keeping that in mind, can butyl rubber be used in applications where the fasteners doesn't penetrate the hull or deck? For example, on our Catalina 30 some cabin-top hardware (deck organizers, winches, etc.) is anchored by nuts embedded in the core. If you tighten these bolts over a number of days won't the seal between the BR and the bolt be broken?

only if you over tighten its one of those things that you need to know when to stop cranking down on the bolt or nut

 

[Maine Sail]

It can work but I would advise body weight to aid in "setting" the butyl. Get a solid 200+ pounder to stand on the winch while you snug it..

Bed-It Tape does not change consistency so waiting to tighten is different than it is with a "curing sealant".... You are merely waiting for it to "displace" not cure...

If you make the butyl cones slightly longer on the machine screw this helps with screw sets.... Keep in mind this works with Bed-It Tape and I certainly can not guarantee success with butyl tapes not specifically formulated for bedding deck hardware as there are major variations and literally hundreds of formulations.

 

[George Da Porge]

OK - I did just get 2 rolls of Bed-it Tape. Was hoping to do this today but high temp is only going to be about 45 deg. Too cool??

Please clarify - in a thru bolt situation w/Bed-it Tape, ideally only the nut is turned, correct?

With my winches and DOs, I won't be able [necessarily] to put the bolt through the base and build the cone around it - when I put the bolt in the hole it will get pushed up when it gets to the nut.

In these cases, how does turning the bolt several times to tighten affect how the tape "binds" to it?

Thanks!

 

[Maine Sail]

OK - I did just get 2 rolls of Bed-it Tape. Was hoping to do this today but high temp is only going to be about 45 deg. Too cool??

Not too cool it just slows the displacement...

Please clarify - in a thru bolt situation w/Bed-it Tape, ideally only the nut is turned, correct?

In an "ideal" situation yes. Sadly placing metal bits into decks and threading into them is not "ideal" but rather it is what it is so we make do and it can work...

With my winches and DOs, I won't be able [necessarily] to put the bolt through the base and build the cone around it - when I put the bolt in the hole it will get pushed up when it gets to the nut.

This will require two people one to hold the winch and one to snug the bolts. Again deck inserts are not ideal but they save production money....

In these cases, how does turning the bolt several times to tighten affect how the tape "binds" to it?

Thanks!

If done properly if works fine but it is a bit tricky due to the inserts.... If in doubt a marine sealant such as Sika 295UV can be used instead...

 

[George Da Porge]

Thanks for all the info Maine Sail!!