FRP (Not the kind you think...)

[PorFin]

Gurus -- I'm a bit curious.

I'm rebedding a couple of places this week (a portlight frame and my chainplates), and I've discovered something that strikes me as, well, unexpected.

It seems that the folks who built our boat (Bluewater Yachts in Taiwan) used a gauze-like fiber to reinforce the polysulfide sealant when they installed/bedded the hardware. It's proving to be quite tenacious and a RPITA to dig out.

Thus a couple of questions:

- Can anyone think of a compelling reason as to why they may have done this? My first thought was that it served as a backing material to keep the sealant from oozing away from the business end of the job, but after seeing how tightly it's packed around the chainplates I'm not so sure.

- How much of this do I need to dig out before I rebed the hardware?

Oh, and Happy Thanksgiving to all!

PF

[NOLAsailing]

Can you post a photo? I'm curious about what you're describing and a visual would be helpful.

When you're rebedding, you need to remove all of the old sealant and, I'm sure, the "gauze" as well. You need a clean curface so the new sealant bonds well and forms a water tight barrier. Any contamination will compromise that.

As for the "gauze," I can't think of any possible benefit. Sealant does not need to be held in place. In fact, you want some sqeeze-out to create something of a gasket around the whole piece of hardware.

[merc2dogs]

We used to use a gauze backed sealant at work, was basically a caulk on cloth. placed it over whatever surface required it, then coated that with a regular tube caulk.
When the caulk set up it was indistinguishable from the tape, so it looked as though the gauze was put in the caulk while it was wet.
The caulk backing was pretty much just to allow it to span gaps without filling them or allowing the caulk to run down inside, used instead of backer rod when the gaps were oddly sized or shaped.

Sounds like that may be what you have.


Ken.

[seabreeze_97]

That sort of thing is still used to build traditional style wooden shrimping boats. I saw a program on it a few years ago. Been used for a loooong time.