What sealant to use?

[BroncoJohn]

I am chasing a leak in the corner of this deck window. What sealant should I use to rebed this window?

So dar the 3 different ones I have used all failed.

 

[markwbird]

Which ones have you used? Maybe your'e doing something wrong. 3M 5200 is the sealant of choice for marine use but you have to apply it correctly

 

[Don S/V ILLusion]

Which ones have you used? Maybe your'e doing something wrong. 3M 5200 is the sealant of choice for marine use but you have to apply it correctly

5200 is not a sealant. It is an adhesive.

 

[Ralph Johnstone]

For minor leaks through the original factory installed sealant, which was DC 795 try this :

Here's a sequence of repairs for one section of the front hatchlight after I suffered a microscopic leak for a couple of years.

 

[Dalliance]

Rebed it with Dow 795, black and use masking tape. Excess sealant will squish out and you want it on the masking tape rather than every adjacent surface.

 

[kappykaplan]

Rebed it with Dow 795, black and use masking tape.

 

[dlochner]

Which ones have you used? Maybe your'e doing something wrong. 3M 5200 is the sealant of choice for marine use but you have to apply it correctly

This is bad information. 5200 has limited uses on a boat. It is a polyurethane adhesive with minimal sealing qualities. It is a permanent adhesive for applications that require high bonding strength and modest flexibility. There is a reason it is often referred to as the Devil's Glue. While the 3m literature suggests 5200 is suitable for installing ports, they are referring to more traditional framed ports not the unframed kind the OP has.

Dow 795 and GE Silpruf caulks are much better choices for installing acrylic panels. These caulks are glazing sealants used to secure plate glass windows in high rises. While both are silicone, they are not the same chemistry is the typical marine or household silicon.

DOWSIL™ 795 Silicone Building Sealant

A one-component, neutral-curing, medium modulus silicone sealant intended for weatherseal and structural applications with excellent adhesion to a wide range of materials, including glass, metal and aluminum. Sustainability: Low embodied carbon DOWSIL™ Silicone. Project specific DOW Carbon...

www.dow.com

Another alternative is to use 3m VHB tape followed by Dow 795 to seal the edges.

In the end however, the cause of this leak and separation is not the sealant, it is inherent in the design of the port. In order to get the acrylic to bend to the boat's curves, it needs to be heat set and baked in an oven to the correct shape. There is some flexibility in the acrylic after it is heat set, however, it the heat setting is off a little, it will put tension on the lens which will pull the lens away from the cabin top. It was an aesthetically pleasing and stylish solution to providing more light to the cabin, but it has limitations.

 

[JamesG161]

I had same issue.

I sealed from the outside with this.

Jim...

PS: Adhesive with great Temperature Range.

 

[Crazy Dave Condon]

Dow 795 is the choice of manufacturers. Some boat windows temporarily used screws til the window seated itself and then removed withe holes filled in with Dow 795. The screw holes were larger than the screws to keep the window from cracking. 5200 is not to be used at all in this application

 

[Leeward Rail]

This is bad information. 5200 has limited uses on a boat. It is a polyurethane adhesive with minimal sealing qualities. It is a permanent adhesive for applications that require high bonding strength and modest flexibility. There is a reason it is often referred to as the Devil's Glue.

Damn. I am saving that post. I wish more people realized the details you put in that post. Unfortunately people keep saying. "Use 5200" and repeat the falsehoods.
If I could give you 1000 helpfuls I would.

Maybe we need a single post sticky with details about the different types.

 

[artboas]

Damn. I am saving that post. I wish more people realized the details you put in that post. Unfortunately people keep saying. "Use 5200" and repeat the falsehoods.
If I could give you 1000 helpfuls I would.

Maybe we need a single post sticky with details about the different types.

You need to pull the window, and then re-seal with either 795 or Sikaflex.
I wrote a comprehensive article (it’s posted) on how to get the window out very easily.
Don’t just lather more externally. It won’t solve your problem reliably .

 

[Stu Jackson]

3M 5200 is the sealant of choice for marine use but you have to apply it correctly

This is so very, very wrong.

5200 is
SATAN’S GLUE

Should be banned from sale to unsuspecting mariners! It is an adhesive, not a sealant.

 

[Dalliance]

Damn. I am saving that post. I wish more people realized the details you put in that post. Unfortunately people keep saying. "Use 5200" and repeat the falsehoods.
If I could give you 1000 helpfuls I would.

Maybe we need a single post sticky with details about the different types.

Good idea about the sticky post. This is a recurring topic.

Go to the websites of certain major marine distributors and it’s easy to see how so many misguided souls are drawn to the Devil’s Glue. The marketing machine for 5200 is running full tilt.

 

[MikeHoncho]

5200 isn’t Satans glue. It’s Satans sealant. 5200 is amazing adhesive.

 

[Dave]

I've heard the call. From the Admin perspective it is who has the credentials to post a meaningful sticky that won't get us in trouble.

If there was to be a sticky on sealants and adhesives it would need to be factual and data based. The person posting would have to have the credentials to make the recommendations. And I'm not sure what liability SBO might have if someone followed the recommendations and there was an unfortunate consequence.

That said, I think there is a real need in the boating forums for good and accurate information. I am open to suggestions on how to do this in a way that does not place SBO in any kind of jeopardy. That's important because only an Admin or Moderator can make a post sticky. I'm not a lawyer, but I have friends who are, if a Mod or Admin makes a post like this sticky it could be interpreted as an SBO endorsement.

So, I'm all ears. If you have suggestions I'd be glad to read them.

 

[Leeward Rail]

So, I'm all ears. If you have suggestions I'd be glad to read them.

Data is easy.. all the products have data sheets.
They will tell you if they damage acrylic etc.

Another option is to quote a noted and knowledgeable sailing authority. Just like a sticky of Rod's work here.
I have a copy of a post done by such a person. I will send it to you and you can take a look.

Or, in keeping the United States of Ambulance Chasers.. couldn't you just have a "the post is the opinion of the moderator. Professional advice from the manufacturer of the products should be adhered to at all times". Or some other CYA stuff.

 

[JamesG161]

Simple answer is here.

SailboatOwners.com

This part is key...

• SailboatOwners.com assumes no liability for the accuracy or reliability of any information posted on this web site. It is not checked, verified, or edited, and is used at your own risk.

______
For a while, we used this area for...

Repeating Stuff

Topic information, FAQ

I asked Phil, if it was still monitored in 2017, he said yes.
But not really.

I added this one in 2017 for repeats.

"Fuel Filters"

My 2 cents and per my brother, who is a Lawyer.

"My advice is worth what you paid for it"

Jim...

 

[Dave]

Jim,

Thanks for the information. The TOS statement does offer some protection, however, it doesn't prevent someone from filing a suit. Also, I believe there are some court cases now about the responsibility of social media providers for content on their platforms. Making a post sticky can not be done by just any one, it can only be done by someone the company has empowered to do so. Thus, an argument might be made that since a representative of the company highlighted the post, it was an endorsement of the post.

I wasn't aware of the Topic Information forum. I need to investigate this as it seems to be disabled for new threads. I tried to open a new thread and I wasn't allowed to. Hmmmm.

Dave

 

[JamesG161]

My point exactly.

Rarely use a "Sticky Post" and never for repeating stuff.

If my no coffee brain is working,
Phil told me when they updated software, "FAQ" link, there was a bug in that section.

Jim...

 

[Don S/V ILLusion]

I've heard the call. From the Admin perspective it is who has the credentials to post a meaningful sticky that won't get us in trouble.

therein lies the problem - who chooses the credentials, how credible is that choice, what criteria (subjective) are used, can advice be perceived as authoritative even though it’s not so as to the point of blame and what liability accrues to the person or entity supplying the information.

there can be unintended consequences regardless of how well-intended the advice is.

The fundamental question administrators should be asking is - why take the risk?