[Summercamp]

I need to rebuild all six of my bronze portlights on a 1978 PSC25. Three have broken glass, all need new gaskets. I am weighing the idea of doing it myself versus sending them off to be re-built. I'm on a budget here. They have already been completely removed from the boat by the previous owner. Some of my basic questions are:

1. Would thick tempered glass be best to use? Was this stock for 1978 and is
this still the best option? I could have a glass company cut the glass and I
would do the rest. Any hints on what type of glass I should ask for? I also have a quote from Atkins & Hoyle for a complete rebuild and it appears the perference is tinted Acrylic. Any opinions on acrylic and where I might buy a sheet?

2. Gaskets - I have read McMasters might be a good source. Any ideas from anyone that has done this?

3. Has anyone done this? Any helpful hints? I am looking for some
instructions on the web and have found loads of opinions (several here) on the type of sealant to use (silicone, butyl tape, poly).

Many thanks!

 

[JohnRPollard]

summer,

I rebuilt the portlights on our 1986 Dana 24, way back when before the age of digital cameras (I was a late adopter ). So I don't have any good photos to show you.

But I can say that rebuilding them is well within the capability of most boat owners. It actually makes for a nice winter project if you have a good work bench where you can set-up.

Our portlights were still mounted in the boat. There were no problems with the frames -- only the sashes needed work. So I removed the sashes two at a time (one large and one small), covered the portlight with a plywood clamp contraption, brought them home, rebuilt the pair then brought them back to the boat and swapped them for the next pair.

You are in some ways fortunate that you can take them all home at once and set-up a production line. But just make sure the exposed portlight openings are well sealed against the elements.

Yes, acrylic is the way to go. Just get one large and one small portlight lens out, then bring them to your local glass shop and they can cut new ones for you at a very reasonable price if you don't need it tomorrow.

To get at the portlight lenses, you will need to remove the flange from the sash. First remove the old gasket, which will expose a series of machine screws. Expect many of these little brass machine screws to crumble when you attempt to extract them. You will have to drill them out carefully. Get yourself a little tap and die kit if you don't have one, and be sure to use loctite or similar when you install the new machine screws into the flange.

I ended up rebedding the portlight lenses with a non-acidic silicone sealant, which actually worked quite well. But there are probably better lens-bedding materials -- Mainsail might have a good suggestion.

I obtained replacement sash gaskets from the OEM, Whitewater Marine. They fit perfectly and were easy to install.

I buffed out the bronze portlights using the little B&D Mouse polishing kit -- they looked like gold when I was done. Very pretty.

After re-installing the portlight sashes, there is one final crucial step: Within the hinge mechanism is a tiny set screw which must be adjusted such that the portlight sash seats evenly around the portlight frame when it is closed. Some trial and error is necessary. Over time, as the new gaskets compress some, you will need to readjust the set screw.

Good luck!!

 

[cormeum]

We went with tempered glass for ours (1/4"). Can't be beat for longevity. if you have to go thinner, use acrylic. We used butyl rubber mastic for the bedding rather than silicone.

 

[JohnRPollard]

We went with tempered glass for ours (1/4"). Can't be beat for longevity. if you have to go thinner, use acrylic. We used butyl rubber mastic for the bedding rather than silicone.

Make sure that you are using tempered safety glass. Were you able to find a single layer(solid), tempered safety glass?

I think your choice of butyl mastik was better than the silicone I used. If I did it again I'd try to locate some for the project. The silicone works (make sure it's the non-acidic variety), but can be a bit unwieldy/messy.

As mentioned, we went with acrylic lenses instead of using the tempered safety glass. The OEM portlight lenses are laminated saftey glass, which is the reason that the portlights begin to fog/haze. As the lens bedding gets older, it begins to fail and allow moisture ingress around the perimeter of the lens, which then wicks up between the glass layers and causes the hazing/fog.

[This is why I prefer the functionality of the newer rectangular PSC bronze portlights -- they use a single gasket to both seal the sash and the lens, i.e. there is no separate flange.]

Also, we had one of the laminated safety glass lenses "spider web" when we were hit by a large power boat wake. The portlight sash was open, and the wake rocked us severely enough to dislodge it from the overhead clip, when it slammed shut against the frame and shattered. I think the wake came from a PSC Fast Trawler.

Lexan is stronger than acrylic, but less UV resistant. The porltight lenses are small enough that I was comfortable with acrylic. But either way, with Lexan or acrylic, you shouldn't have to ever worry about a cracked glass lens or moisture wicking between layers of glass.

 

[cormeum]

Make sure that you are using tempered safety glass. Were you able to find a single layer(solid), tempered safety glass?

Yes, it had to be ordered and we had to supply dimentioned drawings. LOF stamped and everything.

Torrensen glass in Chicago.

 

[dieselboy]

Ive redone mine not brass though and after all the work and research i stuck with double laminated glass.
I have a few pics up . Hope they help.
http://www.sailnet.com/forums/gear-maintenance/58029-portlights.html