Window caulking question

DC61

I've posted enough I should edit this section
Dec 28, 2011
951
1,210
Dana Point
Name
Paul L.
Boat
33’ Blackfin
Hello all,

I have glass front windows on my pilot house. The caulking has worn away and I need to replace it. What do you recommend?

I will caulk it where the glass meets the gelcoat. Thanks in advance!
 

dcarlisle

Captain
Jun 25, 2008
644
433
The Island
Name
Dave
Boat
Boatless
Hello all,

I have glass front windows on my pilot house. The caulking has worn away and I need to replace it. What do you recommend?

I will caulk it where the glass meets the gelcoat. Thanks in advance!
The easy answer is Sika Flex. The reality is that there are sooooo many good products out there these days that there is likely a specialty product that’s specifically for your installation.
When I was running the boatyard, I would sometimes just call either 3M or Sika USA and talk to customer service and give them the exact details of the project and they would recommend which product to use.
Sometimes their answer would be something along the lines of:
“ most people just use XXXXX, but we make this YYYYYY Product that’s specifically for that application. It has all the strength of XXXXX, but cures (faster/ slower/ etc) And is more removable down the road.
some of these guys at the help desk really know their stuff and can be a lot of help. This goes with the paint manufactures as well.
Hope this helps.
 
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DC61

I've posted enough I should edit this section
Dec 28, 2011
951
1,210
Dana Point
Name
Paul L.
Boat
33’ Blackfin
Thank you for the response. Is Sikaflex available at home depot? Do I need to buy a "marine" type of Sikaflex or is it all the same?
 

dragonballs

I'm off probation
Mar 28, 2008
9,204
7,904
Arlington WA
Name
Vance
Boat
40' ocean sport fisher
Sealants and adhesives are different. Talk to the experts or google the application. You are going to want something for uv for sure.
 

Fearlessfiasco

Loco Leftist...
Jun 5, 2012
221
251
La Mesa
Name
Jeff
Boat
Sea Pro 170DC & S/V Lunar Dawn a Casade 36' Sloop
Butyl Rubber is another option worth considering.

I have stuff real similar to this in the windows of my sailboat. Does the job.

Amazon product
 
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dcarlisle

Captain
Jun 25, 2008
644
433
The Island
Name
Dave
Boat
Boatless
Thank you for the response. Is Sikaflex available at home depot? Do I need to buy a "marine" type of Sikaflex or is it all the same?
I buy it at San Diego Marine Exchange.
Again, call the manufacturers first, because I’m still not sure if you are “gluing” in frameless windows or just “sealing” in framed windows that have mounting screws.
As said about, adhesives, sealants, and adhesive sealants are all different and you need to get it right. And a very good point was made that it definitely needs to be UV stabilized.
 

eric perez

stillapinhead
Mar 3, 2018
522
656
Newport Beach Ca
Name
eric perez
Boat
no mas
is there a flat surface where the glass lays in flush? I work for an aluminum window manufacture... we use 3M VHB tape to hang glass... once its down though... its not coming off. But it will be air tight / water tight. And it isolates the glass from touching any fiberglass or metal so you wont have any creaks or rattles. Then you can just run a beauty bead around the perimeter... we use Dow 799... or 1199... flexible and wont crack. comes in clear too...

3M4945075-2T.jpg
 
Jul 9, 2003
1,188
853
Santa Barbara
1212
Name
Gary
Boat
The Right Kind - 31' Cabo Express
Black silicone. Clean the gap around the glass, mask both surfaces (glass and fiberglass), fill the gap with black silicone, squeegee with a soft flex putty knife or plastic squeegee removing excess sealant. Remove the tape before the sealant takes a set. It takes some practice to get the timing of pulling the tape and removing excess but it looks factory finish clean when dried.
ps...if the gap is 3/16" or less you could just use your finger like caulking a crack. Good luck
 
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invictus

AVD
May 26, 2006
4,160
1,676
Orange County
Name
Jason
Boat
Tiara 2000 Cuddy
I refitted a deck light/hatch. The adhesive/sealant had basically turned to powder after 3 decades. I used Boat Life, Life Seal. Made for both qualities and UV/weather additives.