Replacing recess fixed ports w/stainless steel trim

[patrscoe]

I recently purchased a S2 11.0A which if you are not fimilar with this sailboat, she has large fixed port lights that are recessed mounted into the cabin. One of the things I need to do is to replace the glazing / lexan panels within these ports as they are very scratched and the previous owner installed three of the panels in two pieces instead of one.

I have read that an upgrade to fixed lexan ports should be bolting a stainless steel trim within these openings and then silcone the lexan panels into the trim. Although these are large ports during the production timeframe of these sailboats but now a days, it seems like most newer sailboats have large fixed panels that are recessed into the cabin.

I have never seen any type of modification performed on a S2 but then again there were not a lot of S2s built compared to Pearsons and others.

Question is:
- To be seaworthy, should a stainless steel port trim be installed?
or
- Provide a metal trim around the glazing which would be bolted through into the cabin? This would be surface mounted but would provide a continuous bearing trim plate to bolt through instead of bolting through the lexan and risk cracking.
or
- Reinstall (with new panels) properly and caulk them in as originally performed?

[mitiempo]

They are pretty large.

How wide is the flange the glazing sits on? I don't see any advantage of stainless inside the recess if it is wide enough and strong enough, as it should be. Stainless on the outside to sandwich the port between it and the recessed portion of the cabin side would as you say even out the load of the fasteners but they shouldn't be so tight that there is much pressure anyway. The fasteners, with modern compounds like Dow 795, are really only there to hold everything in place until the sealant cures. It would look good but would be pretty expensive. If you did this powder coated aluminum would be another option. If they are as flat as they appear fasteners should not even be required, just a method of holding them in place until the 795 sets.

How thick is the plastic, or how thick does the plastic have to be to sit flush with the cabin side on the exterior?

I would use acrylic (Plexiglass) as it is certainly strong enough and will last many years longer than Lexan. It also will not scratch as easily and doesn't craze as easily as Lexan. They were probably acrylic originally, as are most hatches.

[Faster]

Originally Posted by patrscoe

....One of the things I need to do is to replace the glazing / lexan panels within these ports as they are very scratched and the previous owner installed three of the panels in two pieces instead of one.

Are you saying the three of these ports are done in two pieces? If so how was the seam handled?

From the pictures Brian posted it looks like there's an adequate flange molded in for the bedding compound/sealant to take hold. I'd second the recommendation of Acrylic over Lexan... and would leave an expansion gap around the perimeter of the lens when you reinstall them. There are some good threads here on the subject already. You have a nice base to work with (with the recesses molded in and minimal curvature) as opposed to flush mounting as we had to do.

We've also had very good luck with Dow Corning 795 though I understand that Sikaflex and GE make similar equivalent products.

To assist with cleanup, dry fit the new lenses and mark the inner perimeters carefully, then trim and remove the paper coating in the bonding area only... mask the inside surfaces if the port opening too. On the outside leave the paper on and mask the border of the recess. DC 795 'tools' quite nicely and you should end up with a nice looking job.

[patrscoe]

Faster, yes for some reason the previous owner installed two pieces and silicone the seam. Not sure why, perhaps he ran out of material.

Budget is a concern and I don't want to spend $3k - $4k on the ports for minimum results.
What I have read is that the glazing / plastic is 3/16" thick but could go up to 1/4". I need to remove, provide temporary protection from the weather and investigate what I have here although I would like to have a plan and material in place prior to this.

Another thought and what I really prefer is to reduce the height of the ports by providing a white 1" filler piece (maybe painted alum or stainless) on the top and bottom. This would have a strong flange for the plastic panel to sit in. The problem is that I don't want this to look like a afterthought and also reduce the seaworthyness of the port by adding another seam to fail or leak.

[Faster]

I think that replacing what's there as is would look best and avoid the possibility of it looking odd when it's all done.

Going to 1/4 acrylic won't be all that expensive... the sealant/adhesive is only around $10 a tube and you'd probably use no more than 4. Getting the old ones out may be the challenge. If you do get them out in one piece they could be used as templates to cut the new out with a router (plastic shops generally do this for a nominal fee), otherwise you could provide plywood templates.

Making the ports smaller overall, besides the difficulty of making it look 'right' will also cut down on the light below.. it's nice to have a naturally bright interior. New ports will make that even noticeably better if the current ones are becoming opaque.

btw do a search for some of Mainesail's recent posts - he had a good tip about acrylics in the past few weeks..