Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 19-01-2020, 13:05   #1
Registered User

Join Date: Aug 2010
Location: Ontario
Boat: Beneteau
Posts: 13
Send a message via Skype™ to Old Hand
Window sealant for outside mounted plexiglass

Hello all, I know this has been covered many times and there are so many choices of sealants. I have tinted windows on my First 285 Beneteau that are through bolted directly in the cabin top. I removed the foam tape years ago from being dried out and leaking. I've used butyl tape with good success in the sealing department but it is sticky, collects dirt, and more importantly it gets soft in the heat and runs. It need to be tightened down to reseal and than gets squeezed out and after a few seasons is a mess and no longer seals. I have taken the windows out again.... seems like a job to be done every few years. I'm now wondering if there is a better sealant that will not run but will seal around the bolts and still let the windows be removed in the future without a cutting wheel?
__________________

Old Hand is offline   Reply With Quote
Old 19-01-2020, 13:23   #2
Registered User

Join Date: Jan 2018
Posts: 1,456
Re: Window sealant for outside mounted plexiglass

There are lots of types of butyl tape. They make stiffer ones that won't melt in the heat. Possibly this your best bet?

I know the basic gray one they sell in Ace hardware here in the states in the plumbing section is very tolerant to heat. Possibly they have something similar at Canadian Tire?
__________________

Chotu is offline   Reply With Quote
Old 19-01-2020, 16:12   #3
cruiser

Join Date: Jan 2017
Boat: Retired from CF
Posts: 13,304
Re: Window sealant for outside mounted plexiglass

Ask Maine Sail about his
https://shop.marinehowto.com/products/bed-it-tape

Current other thread
http://www.cruisersforum.com/forums/...d.php?t=229125
john61ct is offline   Reply With Quote
Old 19-01-2020, 18:10   #4
Registered User

Join Date: Oct 2015
Posts: 1,768
Re: Window sealant for outside mounted plexiglass

I will second the comment that all butyl tapes are not the same. They are made for different purposes, with different properties. You used one not appropriate for the application. Remember, up until recently, butyl tapes were the way that all car windshields were installed. They didn't have the kind of problems you report.

BUT...

If you use a proper adhesive sealant like Dow 795 or GE SCS2000 you will never have to remove the window until it has scratched or sun crazed so badly that it needs replacing. So who cares if you break it getting it out?
billknny is offline   Reply With Quote
Old 19-01-2020, 18:22   #5
Registered User
 
gamayun's Avatar

Join Date: Aug 2013
Location: Oakland, CA
Boat: Freedom 38
Posts: 2,120
Re: Window sealant for outside mounted plexiglass

I've been very happy with 3M 4000 UV. Clean up the edges that ooze out with alcohol before it sets completely.
gamayun is offline   Reply With Quote
Old 19-01-2020, 18:27   #6
Registered User

Join Date: Dec 2009
Location: Australia
Boat: building Roberts Mauritius 43ft
Posts: 1,380
Re: Window sealant for outside mounted plexiglass

I had serious doubts about using an adhesive to secure the toughened glass ports on my yacht.

But having used it I am supremely confident. I used the same adhesive that auto-makers used ti fix windscreens into motor-cars.
coopec43 is offline   Reply With Quote
Old 20-01-2020, 09:20   #7
Registered User
 
SVTatia's Avatar

Join Date: Jul 2007
Location: Toronto, Canada
Boat: Luders 33 - hull 23
Posts: 1,204
Re: Window sealant for outside mounted plexiglass

Quote:
Originally Posted by gamayun View Post
I've been very happy with 3M 4000 UV. Clean up the edges that ooze out with alcohol before it sets completely.
Either that or: Dow 795, Sika 295 with primer or just EPDM rubber from McMaster Carr, the stuff they use on car windows - weather resistant EPDM rubber.

https://www.mcmaster.com/rubber

Butyl is great but it has its cons: it tends to ooze for a while, specially on very hot days, collects dirt, and it also "runs" - a dark grey ooze that needs to be cleaned up from time to time. I don't think I would use it for this purpose. And this is "the" Butyl, the one from Maine Sail.

Previous discussion on similar topic:

Fixed window replacement - Dow 795 still the sealant of choice? [Sitemap] - Cruisers & Sailing Forums
SVTatia is offline   Reply With Quote
Old 20-01-2020, 10:34   #8
Registered User

Join Date: Jan 2014
Location: Ft. Lauderdale
Boat: Watkins 29
Posts: 254
Re: Window sealant for outside mounted plexiglass

Quote:
Originally Posted by Chotu View Post
There are lots of types of butyl tape. They make stiffer ones that won't melt in the heat. Possibly this your best bet?

I know the basic gray one they sell in Ace hardware here in the states in the plumbing section is very tolerant to heat. Possibly they have something similar at Canadian Tire?



I bought some at Home Depot that is used for sealing metal roofs. Its very heat tolerant.. and seems to be working great on all my deck hardware and the lens in my old Bomar deck hatches..plus...its inexpensive. I think I paid $5.00 US for a roll that will last me a few years.
dennismenace111 is offline   Reply With Quote
Old 20-01-2020, 11:27   #9
Senior Cruiser

Cruisers Forum Supporter

Join Date: Sep 2007
Location: Enkhuizen, NL
Boat: Pearson 36-1
Posts: 505
Send a message via Skype™ to George DuBose
Re: Window sealant for outside mounted plexiglass

After 10 years of fighting with my Pearson's 3/16" safety glass which isn't available anymore, having mildew growing between the layers, cracking when reinstalling, I have a new plan...

I want to bond 1/2" Lexan directly to the exterior aluminum frames with 3M's VHB, a double sided acrylic tape. It comes in various thicknesses and widths and is supposed to be water and UV resistant.

Due to the expansion of the Lexan, I am still considering what sealant to create a bead around the exterior edge of the Lexan.

Currently considering 3MTM OEM Polyurethane Glass Adhesive Sealant 590.

I will paint a border around the inside of the Lexan with possibly POR-15, but I need to do more research on what paint bonds to Lexan. I just don't want to see the beige VHB through the Lexan.
George DuBose is online now   Reply With Quote
Old 20-01-2020, 19:39   #10
Registered User
 
allatsea99's Avatar

Join Date: Dec 2015
Location: Australia
Boat: Mumby 48
Posts: 20
Re: Window sealant for outside mounted plexiglass

Maybe a v low modulus silicone. In Australia where temperature ranges are extreme Iíve used Sealproof by Adhseal. Itís v v low modulus like a hard jelly - great for heat & dealing with plexiglass/ polycarbonate expansion. Used to use it bonding CRT tv tubes to tv screens.
allatsea99 is offline   Reply With Quote
Old 20-01-2020, 23:39   #11
Registered User

Join Date: Aug 2011
Location: New York, New York
Boat: Dufour Safari 27'
Posts: 1,185
Re: Window sealant for outside mounted plexiglass

following
ArmyDaveNY is online now   Reply With Quote
Old 21-01-2020, 01:08   #12
Registered User

Join Date: Aug 2019
Location: New South Wales - Australia
Boat: Boatless :( (for now)
Posts: 25
Re: Window sealant for outside mounted plexiglass

Hi Old Hand,

I would only trust Sika products (be sure to use primers and try times) for any window fittings, no matter if its glass or plastic, metal trim ect.

Had too many issues with other products over the years.

We were able to use Sika on a sport boat that was previously through bolted, allowed for a bigger flange and did away with the bolts. No plastic cracking and modernised the boat. I'm sure a different story if your going offshore.

Good luck!
__________________

boatbroke is offline   Reply With Quote
Reply

Tags
sealant, wind

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fixed window replacement - Dow 795 still the sealant of choice? bstreep Construction, Maintenance & Refit 61 20-01-2020 18:29
Making outside window coverings shirlagrace General Sailing Forum 2 02-12-2015 16:40
Window screen to cover a sliding window sdowney717 Construction, Maintenance & Refit 2 14-11-2012 06:59
Adding opening ports to a Plexiglass Window Curtis Construction, Maintenance & Refit 3 09-07-2007 14:11
Sealant for Plexiglass Hatches svcattales Construction, Maintenance & Refit 17 05-01-2006 16:34

Advertise Here


All times are GMT -7. The time now is 11:30.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.