Proper sealant to use on hatch between “glass” and aluminum frame

[motoryacht lover]

Proper sealant to use on hatch between “glass” and aluminum frame

What is the proper sealant to use between the Lexan ?? And the aluminum frame of the hatch. These are bow hatches. Thanks for your time.

 

[Boatsb]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

What's the aluminum coated with?

 

[motoryacht lover]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

I don’t know.

 

[Boatsb]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

lexan is Polycarbonate and I believe pure silicone is a good sealant. Aluminum could be painted, powdercoated, anodized or clean.

Im not sure whats best for that bond.

BobK please chime in.

 

[SEVEN]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

I’ve seen silicon and 4200 used.

 

[motoryacht lover]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

Thank you both for your help. I really appreciate it.

 

[bobk]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

lexan is Polycarbonate and I believe pure silicone is a good sealant. Aluminum could be painted, powdercoated, anodized or clean.

Im not sure whats best for that bond.

BobK please chime in.

Polycarbonate is very easily damaged by some solvents. I would check with a plastics supply house rather than reinvent the wheel. It is also not very UV resistant.

Silicone caulks come in several flavors. The common one releases acetic acid when it cures which may damage the aluminum. An architectural polyurethane may be best if it will not damage the PC.

Bobk

 

[doc g]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

`Dow 895 is what is used by most that rebuild them.....Pat

 

[Scarlett]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

I don't know about Dow 895, but I use Dow 795 which is a commercial grade silicon, my entire aft deck enclosure is put in with the 795. It is plexiglas but it is also good for lexan and regular glass. As I understand it the windows in skyscrapers are glued in with 795. Only problem with it is can be hard to find. We found a place that was a boulders supply and they sold it to me at wholesale pricing and it was surprisingly cheap. The guy that replaced my solid glass windows on my last boat used it also. John

 

[SKYCHENEY]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

Boatlife Life seal. Its a combination silicone/polyurethane. Its safe for Lexan. I used it on my hatch years ago and its still watertight.

Read about it here:

http://www.boatlife.com/lifeseal-sealant-cartridges/

 

[jrbrein]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

Boatlife Life seal. Its a combination silicone/polyurethane. Its safe for Lexan. I used it on my hatch years ago and its still watertight.

Read about it here:

http://www.boatlife.com/lifeseal-sealant-cartridges/

Sky,

Does the silicone in this mixture result in any staining with dirt or streaking on your paint? I have been re-bedding fittings on my boat that were done long ago with silicone and I hate the stuff.

Jon

 

[SKYCHENEY]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

Sky,

Does the silicone in this mixture result in any staining with dirt or streaking on your paint? I have been re-bedding fittings on my boat that were done long ago with silicone and I hate the stuff.

Jon

No, not that I have noticed. But, I never used anything with silicone in it. If you do, you will not be able to paint it later. The only reason I used it here was I had to find the right stuff to use on my hatch that would bond to both fiberglass and acrylic and allow for the differing thermal expansion rates of the two materials.

 

[KPTIM]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

Consider using Sikaflex 295 UV (available in white or black).
Available from sources like Jamestown Distributor, Boat outfitters, Defender Marine and of course Amazon.

Sam's doesn't stock it because it does have about a 1 year shelf life.
It has all the right words in the description for i.e. bonding Glass, Acrylic, ceramic, aluminum, fiberglass, metal and plastic.

This is what Sam's recommended to me to use putting in my new glass windows in the pilot house helm aluminum frames and the new Lexan port windows in there aluminum frames back in the aft state room.

 

[bigbill]

Re: Proper sealant to use on hatch between “glass” and aluminum frame

i'm getting ready to replace my 3 front windshields, what would ya'll recommend for aluminum frame to fiberglass and also glass to aluminum frame? i have been told instead of using the original rubber gasket that it is better to tape off the frame and glass and make a gasket with sealant. this does not allow any water to get to the frame-glass area like the rubber gasket would. what do yall think? 4 of my side windows have this type of sealant gasket and they have not leaked since i purchased the boat 12 years ago.