More portlight questions

[tartan30cirrus]

On my tartan, I am replacing two ports. The glass is sandwhiched between two frames, an inner and outer, with the barrel bolts going through the frames and fiberglass. I have removed the outer frame and old/cracked glass. The inner frames are stuck on quite good, on the teak veneer which I am afraid to destroy by taking the inner frames out. Why can't I just leave the inner frames on and rebed the outer and new glass? What caulk would make the best seal/gasket? Thanks!

[Tim]

If you're happy with the quality of the seal inside (and it certainly sounds like it's good), I can't see offhand why you would absolutely have to remove the inner frames. It's the outer frames that provide the seal against the elements anyway; most of the time, the inner frames on ports of this design aren't even installed with sealant (like the Triton deadlights).

If you're replacing with plexiglass or lexan, beware that you should not use polysulfide caulk, which can react with other plastics. Silicone is pure evil, so don't use that. Instead, use butyl or butyl caulk. It's very sticky and flexible, and seals extremely well.

[tartan30cirrus]

If you're happy with the quality of the seal inside (and it certainly sounds like it's good), I can't see offhand why you would absolutely have to remove the inner frames. It's the outer frames that provide the seal against the elements anyway; most of the time, the inner frames on ports of this design aren't even installed with sealant (like the Triton deadlights).

If you're replacing with plexiglass or lexan, beware that you should not use polysulfide caulk, which can react with other plastics. Silicone is pure evil, so don't use that. Instead, use butyl or butyl caulk. It's very sticky and flexible, and seals extremely well.

How does this butyl caulk compare to 5200?

[Tim]

DO NOT USE 5200 FOR THIS APPLICATION!

5200 is an adhesive first, and is not for use as a sealant or caulk unless you are seeking a permanent installation. Ports and deck hardware never qualify as permanent installations. 5200 should be used only for structural adhesive applications, such as permanent structural members, installing ballast keels, installing through hulls (and some would argue against its use here), and so forth.

Don't make the common mistake of using 5200 as a caulk or sealant. That is not what it is designed for, and it is a decision that you could regret later--or at least the person who next owns your boat will regret on your behalf.