Port Light Caulk

[normdeeley]

Im refittinh my opening bronze port lights. The cabin sides are about an inch+ thick. The port flange is 1 1/4. There's a petty good gap to fill from the outside. 1/8 to 1/4. Not sure what sealent to use. Thoughts?

[Sailmonkey]

Like th gap between the spigot and the cabin sides?

I've recently become convert to butyl, and did four ports with it. Perfect, no leaks not mess. It does take longer than caulk though.


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[ewsponberg]

Originally Posted by normdeeley

Im refittinh my opening bronze port lights. The cabin sides are about an inch+ thick. The port flange is 1 1/4. There's a petty good gap to fill from the outside. 1/8 to 1/4. Not sure what sealent to use. Thoughts?

Hi Norm,
We used a lot of SikaFlex 291-LOT on our boat, Corroboree, whenever we needed watertight seals but without the permanent adhesive qualities of 3M-5200. "LOT" stands for Long Open Time, meaning it will take longer to get to tack, particularly in the hot sun down here in Florida. We tried the regular SF-192, but it started to go hard in mere minutes.

You can get a caulking tube of SF-291-LOT for $13.99 at Jamestown Distributors, but you can get it at Merritt Supply in Pompano Beach, FL for $6.10, so less than half JD's price. Link: http://www.merrittsupply.com/search.aspx?searchterms=sikaflex+291-lot. .

When using it, tape off the bonding perimeter and keep some paper towels and mineral spirits handy to clean up as you go--it can get on your hands, clothes, and the boat really quickly.

Do you have rubber seals in your bronze port lights, and what condition are they in? We have bronze port lights, and while the frames are well sealed and did not need attention, the rubber seals of the opening window to the frame were shot. We found replacement seals at Downwind Marine in San Diego, CA. Link: http://www.downwindmarine.com/Portlight-Gasket-Seal-Hollow-Black-Rubber-p-90891254.html. We used the smallest size, 1/4" which works really well. We did spot-seal the gaskets with clear GE Silicon II caulking to keep them in place.

I hope that helps.

Eric

[normdeeley]

Thanks Eric, just the kind of info I was looking for. I looked at 5200, but paused. Although I will inn all likelihood never remove these, someone someday might. I don't want them cursing me. I also considered butyl but it would take a lot. And would be too difficult to get it all the way back in the space. I'll price out your suggestsuggestion over here on the West coast of fl. Thanks again

[Rhapsody-NS27]

The builder of my boat, and other owners, swear to using Dophinite to seal portlights. It comes in a small can and has a consistancy of peanut butter. A little goopy but works well. I've only used it myself for installing a teak block as a vent base on deck. While any exposed surface will skin over, it will stay sealed and slightly flexible inside the joint.

After 35yrs, the portlights on my boat haven't leaked from the mounting areas.

[SailFastTri]

Butyl tape.

[BigSmile]

Originally Posted by ewsponberg

Hi Norm,
We used a lot of SikaFlex 291-LOT on our boat, Corroboree, whenever we needed watertight seals but without the permanent adhesive qualities of 3M-5200. "LOT" stands for Long Open Time, meaning it will take longer to get to tack, particularly in the hot sun down here in Florida. We tried the regular SF-192, but it started to go hard in mere minutes.

You can get a caulking tube of SF-291-LOT for $13.99 at Jamestown Distributors, but you can get it at Merritt Supply in Pompano Beach, FL for $6.10, so less than half JD's price. Link: Merritt Marine Supply. Search.

When using it, tape off the bonding perimeter and keep some paper towels and mineral spirits handy to clean up as you go--it can get on your hands, clothes, and the boat really quickly.

Do you have rubber seals in your bronze port lights, and what condition are they in? We have bronze port lights, and while the frames are well sealed and did not need attention, the rubber seals of the opening window to the frame were shot. We found replacement seals at Downwind Marine in San Diego, CA. Link: 404 Not Found We used the smallest size, 1/4" which works really well. We did spot-seal the gaskets with clear GE Silicon II caulking to keep them in place.

I hope that helps.

Eric

Thanks for the tip on gaskets, tucking that one away.

Do you have any tips on how to pull one of these bronze port lights?

The one need to pull for inspection is about 12" long, and the oval tapers at both ends. Not sure the correct nautical term, but the ring that screws on from the outside is already off. Seems like the port is really on the inside of the coachroof, enough that I wish could convince not to bother to take off, but need to get an inspection in that area.

Thank you for any tips or techniques you can share, hoping there's a better method or tool than pry bars.

[steve77]

When I replaced our ports, I used a Fein multi tool with the scraper blade. This blades oscillates back and forth to cut through caulk and bedding compounds. It made short work of a job that can take hours. If you don't have one, other companies (Dremel, Craftsman, etc.) make similar tools.

A little caution will keep you from marring any surfaces that you want kept looking good. Also, tape on the cabin top provides a little extra protection.

Cheers!

Steve

[Reefmagnet]

I'm posting here moreso because I'm about to embark on an identical project - bronze opening port lights mounted into the hull. Port lights of the type that seals from the inside and not the outside. My research is pointing to Dow Corning 791 silicon for this application. I have - and use - butyl and Sikeflex 291 for other projects on the boat but it seems that the Dow Corning product is a highly recommended bedding and sealing compound for this application from my Internet research?

[keepondancin]

Starting with a thin putty knife, you can start cutting the sealant. the Feintool will help also. Make some hardwood wedges from oak or hard maple, and tap them into any gap you create to keep constant pressure on the port light. It will eventually break loose. Go to the New Found Metal website to see their installation directions, you will get some ideas on what to do.

[skipmac]

Butyl tape. A little more work that squirting caulk out of a tube but worth it.

If you have too large a gap between the portlight and cabin trunk you need to add a spacer or trim ring. Look at the teak spacers sold by New Found Metals to see how they work.

[ewsponberg]

The last 4 answers all sound like good advice.

Eric

[normdeeley]

All great answers. I looked for the 291 lot retail here in Naples, Fl.. $20. At West. Ordered from Merrit supply in pompano. I ordered a couple12" lengths of gasket from Carr Mcmaster. 1/4 and 5/16. See what fits. I'm guessing these ports are all made by the same foundry in Taiwan. My boat is an 1984 Kadey Krogan cutter. gaskets are probobly 1/4" as you say. Thanks for all of your help.

[Schooner Chandlery]

Originally Posted by Rhapsody-NS27

The builder of my boat, and other owners, swear to using Dophinite to seal portlights. It comes in a small can and has a consistancy of peanut butter. A little goopy but works well. I've only used it myself for installing a teak block as a vent base on deck. While any exposed surface will skin over, it will stay sealed and slightly flexible inside the joint.

After 35yrs, the portlights on my boat haven't leaked from the mounting areas.

That is a traditional material with a lot of good uses. We carry Dolfinite in the Schooner Chandlery here

I thought the OP was talking about the spigot being longer than the hull/cabin thickness so it sticks out a little far. If that is the case, a teak or metal frame can be used on the outside. Most portlights have holes for fasteners anyway, so one could use the outside trim piece (if metal) and the inside bit to make a secure sandwich with the hull in the middle.

If the OP doesn't like dolfinite, the Sikaflex option is good. Sikaflex used to be an independent company but it is made by the company that also makes Tremco and there are identical products (chemically) used in the building industry under the Tremco name. I can never recall if Sikaflex bought Tremco or Tremco bought Sikaflex. It's probably the latter.

[Cheechako]

To remove them, you have to cut the sealant between the flange and the mounting surface. As mentioned a thin stiff putty knife may do that well. Sometimes I find the little Swiss Army knife, the smallest one they make about $14 is the answer. The blade stays sharp a long time, it is springy and flexes without permanent bending. The body of the knife is thin so you can get the blade in a tight space. I'm amazed at how many times it's come down to using those little knives on all kinds of things. ONLY Swiss Army brand though. It has a blade, a nail file and a tiny scissors... that one.
I refer to put tons of sealant on a port lite and let it squish out. Remove the excess and wipe off. Then do the outer ring. If it's easy to mask off that's great , if not, just remove excess and fillet around the ring perimeter with your finger. Lots of paper towels handy. Acetone or solvent for final clean up on the surrounding fiberglass.
I have often used 5200. "Do it once and forever". But would probably look at an alternative now, as it's not necessary on portlights. The key is to fill all the space completely.