Rob/Nick:
The reason I asked Nick a question about the window style is that my
1978 C&C 34 had the old-style screw-on oval windows, not the newer style "go
fast" windows (which I believe started in '79 or '80). The older windows had
an aluminum frame that simply screwed onto the side of the cabin. Undoubtedly
to address leaks, a PO of my boat decided to thru-bolt the frames and made a
fine mess of things. I decided to replace them with Lewmar opening ports,
which came in a size very close to the oval cut out. Lewmar also makes (or at
least made) a non-opening port of the same size. The issue with the opening
port is creating a flat surface on the curved side of the cabin. My guru
figured out how to do it, and the upgrade was great -- especially given that my
boat did not have a ventilation hatch in the main salon.
Matt
Erie, PA
C&C 42 Custom
-----Original Message-----
From: Robert Abbott via CnC-List <cnc-list@cnc-list.com>
Sent: Wednesday, July 16, 2025 7:29 PM
To: cnc-list@cnc-list.com
Cc: Robert Abbott <robertabb...@eastlink.ca>
Subject: Stus-List Re: General question about caulk, gaskets, and water sealing
Nick<
My boat has two windows on each side, and one, the long one has a significant
curvature which puzzled me as to how I would keep it in place without a frame,
screws, bolts etc. I completed the job 15 years ago and the windows still look
like new with no issues.
First, I removed the old windows using a stiff putty knife which I filed the
edge very sharp and tapped on the inside of the window slowly and carefully
with a rubber hammer to cut the old Plexus.
I cleaned the Plexus from the old windows as they were used as a template to
cut the 4 new windows.
Where the old windows came out, you may find the Plexus lifted some of the
gelcoat....you can fill and smooth over with a filler or just leave it as the
adhesive will take care of it.
At the time, I was not aware of the VHB tape so I used Sika 295 UV and the Sika
Primer......I can not stress enough the need to include the Sika Primer and it
is more expensive that the Sika 295 UV which I used 2 tubes (not all of it but
I needed some of the second tube). The Sika
295 UV will not bond properly without the Sika Primer.
The new windows will have paper on both sides so you have to put them in the
cabin sides and draw around the inside so the paper can be cut away where they
fit into the cabin side. With sand paper, rough up the new window where they
will be mounted.
I taped both the inside and outside of the cabin......the Sika 295 UV is very
dirty stuff....you will need a solvent and lots of rags handy. I applied the
Sika to both where the windows will be mounted, liberally as I wanted it to
ooze out when I pushed the windows into place and some on the edge of each
window itself.
I resorted to cutting 3 pieces of 2" X 4"'s approx 23" long for each window to
brace it after applying the adhesive......I put the 3 pieces of wood against
the window and braced them against the toerail placing a
10 pound rock on each piece of wood to ensure it stayed in place.....left the
braces on for 48 hours to allow sufficient curing time with the moderate Spring
temperature.
I did one window at a time, removing the tape inside and outside, before the
adhesive started to cure.
If I were to do it again and was assured that the VHB tape would address the
curvature issue with the wooden braces, I would use the VHB tape, regardless of
cost. While the Sika 295 UV and Sika Primer is effective, it is more labor
intensive with the application and it is messy if you are not prepared.
Several years back I had to replace my car windshield and they used a Sika
adhesive.....the people that did it said the Sika adhesive they used was
similar to the one I used except the curing time was a fraction of the 295 UV
for obvious reasons.....they don't want your vehicle in the shop for 24 to 48
hours while it cures.
Maybe the VHB tape and bracing will address your curvature.
Rob Abbott
AZURA
C&C 32 -84
Halifax, N.S.
On 2025-07-16 2:50 p.m., Floersch.net via CnC-List wrote:
> I’m a fairly new sailboat owner.
>
> My CNC34 (’78) needs the water sealing around the cabin windows re-done. It
> is not awful but there are certainly signs of age and deterioration and
> despite careful use, the spring power-washing cleaning showed that water
> could get through some of the edges of the windows.
>
> What is the best practice for re-sealing windows?
>
> Is there a particular caulk I use? Or do I use gaskets of some kind?
>
> I could take out the old windows and look at what was there, but I am not
> convinced the previous owners did it the right way either. So I’d like to
> know what is considered the current best approach?
>
> Thanks!
>
> Nick in Vermont
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Your contributions help pay the fees associated with this list and help to keep
it active. Please help by making a small contribution using PayPal at:
https://www.paypal.com/paypalme/stumurray All contributions are greatly
appreciated.
Your contributions help pay the fees associated with this list and help to keep
it active. Please help by making a small contribution using PayPal at:
https://www.paypal.com/paypalme/stumurray All contributions are greatly
appreciated.
