Rebedding windows

[jimesh]

Two years ago I (with help from the yard) completely removed and disassembled the four large main cabin windows and the two small ones in the forward cabin. (Couldn't get the opening ones in between off.) I had the frames black hardcoat anodized (hopefully to make them last a good while longer) and then completely reassembled and reinstalled them. This was originally to fix a few small leaks that I didn't want to deal with piecemeal, as well to help preserve the frames, which I decided were still the best choice for the boat after surveying everything I could find on the market.

By this past winter 3 of the four large main cabin windows were leaking catastrophically along the lower outer edge caulking between the frame and glass. Neither of the small ones forward have leaked a drop. There was major separation between the glass and caulking, which was still well adhered to the frame. In trying to figure out what went wrong I've only been able to come up with two possibilities:

(1) I did not caulk between the inner frame and the glass although I think it was originally done so. Seemed to me at the time unnecessary. :-( When inspecting the failed joints I noticed horizontal movement of the glass in the space between the inner and outer frames. So this theory is that as the hull worked when sailing, on the mooring, or possibly when hoisted and moved in the yard the flex and twist of the hull allowed the glass to pull away from the caulk toward the inside of the hull, lacking inside caulking to trap it tightly in place between the frames. This theory is bolstered by the fact that the large windows failed but the small ones did not over the same time period (more flex in the large ones seems likely.)

(2) Possibly not enough cleaning of the glass before caulking. (I used a lot more acetone this time around you can be sure.)

Caulking was BoatLife black polysulfide which has given me good results over many years.

My question is whether anyone has experience with rebedding the windows, and what you've found to work. Any suggestions as to what I may have done wrong and how to make it work better next time would be appreciated.

PS. We're very happy with the black anodized look of the frames on the boat, but it wasn't cheap. I sure hope it justifies the cost in longevity. I'll have to send in pictures. The opening ports will get it if I can ever get them off -- just removing the screws doesn't seem to help at all. Anyone done this?

[hirover]

Surprized to hear the LifeCaulk didn't do the job. It's always worked for me.

I rebedded one of my large windows with black Butyl auto window sealer that I got at an auto parts store.. The hole was poorly cut with a fairly large gap at the forward lower corner that the frame barely covered.. Wanted to use a 'caulk' that was semi solid at application to fill in the gap where the window barely overlapped the cabin side. The Butyl has sealed the window without a problem, yet. The caulk came in a rope configuration that I wrapped around the window frame. Butyl isn't super sticky so was relatively easy to stick on to the frame but it does instantly bond to itself so is a bit tricky to work with. Butyl will not stick to a wet surface which made installation of the window surprizingly easy. I put the caulk on the window frame, wetted the cabin side around the window on the cabin side and slid the window into place. After I positioned the window, waited for the cabin side to dry before putting the screws in. Butyl stays permanently flexible and sticky so it's not a problem to wait for the surface to dry. I did the job on a cool day here on SF Bay, probably temp around 60 degrees. The caulk didn't compress well when the fastening screws were tightened up. The window stands a a bit proud, though not much, of the cabin. Hopefully it won't seep out when the boat sees it's first warm weather.

This window was previously installed with sillycone and may have been R&R'd to correct a previous leak. The rest of the windows aren't leaking but will be R&R'd for the deck painting next winter. Will probably use Butyl to seal them but will try and find White Butyl for the reinstall. Haven't tried but hear that you can get butyl rope in colors at camper/mobile home places.

If you use Butyl, test it to see if you can use mineral spirits or other solvents for cleanup. The Butyl is easy to clean up just by scraping it off. Had a small patch that got stepped on and pressed into the non skid. Used mineral spirits to try and remove it. The Butyl immediately turned liquid and soaked into the old porous gel coat. Left a gray stain that has gradually lightened to almost gone but it's taken months

[jimesh]

Thanks for the info. Butyl sounds like something worth investigating. BoatLife polysulfide caulk has always worked for me for 40 years of boating. I was very surprised too.

Yes, the original caulking was silicone on all the windows, and also internally for the assembly. The greatest expense for the hard black anodizing was actually getting it all 100% removed.

We noticed the same thing in getting the large windows out the first time. The holes in the cabin sides had apparently been cut without much concern for the actual dimensions of the frames and windows. They were very ragged and uneven. In our case some were so tight in places that the yard worker had to squeeze a saw blade in alongside the frame to enlarge the hole enough to get the window and frame out. Maybe the liner has shifted slightly with respect to the cabin sides after everything was assembled at the factory. That could account for some of what we've seen.

[whitecap]

The catalina direct website sells a kit to redo the main cabin portlights. I have a 1976 Pearson and the kit is an exact match for the glazing and trim. A little expensive but a definite problem solver;

[jmcleodfl]

I used Butyl tape to reset my leaking large windows. The Butyl came in flat one inch rolls. I used a couple of strips of the tape around the edge to fill the large gaps.
The windows are no longer leaking.

Check out this link to Compass Marine.

www.pbase.com/mainecruising/butyl_tape

[seaner97]

I tried rebedding and rebuilding, but the d**n things kept leaking. Bit the bullet and got new ones made that open and have pop in screens for better ventilation. Not cheap, but they don't leak and the cross breeze was worth it.

[msparks378]

Seaner97, how are your new windows holding up?

[seaner97]

Perfect. Not a single issue

[miatapaul]

where did you get the opening ports?

[roverhi]

Even though I'd cured the leaks, decided to get rid of the all the original port lights. Glassed in the 2 areas each side of the main cabin where fixed ports were. Recut for 3 opening ports in the main cabin and reused the openings for the old ports forward.. It was a lot of work but having the opening ports is a huge benefit in the harbor. Used Vetus PM series opening ports for the new lights.

If you decide to remove and rebed the factory ports highly reccomend you seal the cabin liner to the cabin sides. Chasing down the cause of the leaks was a problem because the one port that was leaking allowed water entry into the liner and it exited well away from the actual leak. Used 5200 to cure the cabin side/liner gap. squirted the 5200 into the gap and then clamped the two pieces together and let the 5200 cure before reinstalling the ports.

[seaner97]

I got mine made by Bomar in QC. I pulled the old ones, traced out the outlines and sent the template to the company. Added some MarineTex in white all around and then ground back to where the ports fit perfectly using a dremel.

[msparks378]

Seaner97 - Did you use the foam tape that comes with the Bomon windows or did you use Butyl tape? And How did you manage the variance in the gap between the hull and liner? I have my new windows in hand and I am getting ready to install.

Thanks!

[seaner97]

Jul 29, 2017 11:07:14 GMT -5 msparks378 said:

Seaner97 - Did you use the foam tape that comes with the Bomon windows or did you use Butyl tape? And How did you manage the variance in the gap between the hull and liner? I have my new windows in hand and I am getting ready to install.

Thanks!

Used the supplied. When I set the screws it pulled them tight all around. No leaks 5 years later.