New vent: goop?

[Mark G]

Time to replace the roof vent. What sealer should I use?

 

[ckent323]

Mark,

I have used 3M-4200 and it works well. Other folks recommend Dicor, Sikaflex and Silaprene products (each makes several different sealants and some are better than others)

Here is a post on various sealants:

http://www.wanderthewest.com/forum/topic/15920-good-sealant-for-latch-replacement/

Here is a comparison article

http://www.pbo.co.uk/gear/which-adhesive-sealant-is-best-20877


Craig

 

[ckent323]

Some suggestions from my use of 3M-4200 which may be applicable to other sealants.

5200 is easier to find than 4200. I had to go to a Marine supply store to get 4200. It can be ordered on-line

• It is very sticky and it is easy to make a mess so I recommend wearing surgical type gloves. Have extra gloves within reach so you can change to clean gloves quickly.
• If you get any adhesive on your gloves, stop as soon as you can and change gloves. If you touch anything it will stick to that too and very quickly it will be a mess.
• Clean the surface first according to manufacturers directions. I washed the surface then dried it. Once dried I scrubbed the surfaces with a clean rag and alcohol (quart can from Ace hardware).
• Use blue tape and mask along the edge of where you want the bead, leaving a narrow gap for the bead.
• Cut the adhesive tube tip to give you the bead width you want. I always cut at an angle but I have seen others use a perpendicular cut. Whatever works.
• It is best if you can make one continuous bead along the surface. Each time you lift off and start a new application it will create a bump and maybe a strand that can make a mess if it touches anything. If you touch the material it will stick and each time you pull off it will create a bump,
• Use plastic tongue depressor sticks to smooth the surface to get a nice uniform surface. Start at one end and smooth on one continuous motion. Do not lift off or you will crate rough spots and bumps.
• I used a folded paper towel to wipe some spots and it worked OK but the paper towel then has real sticky material on it and if it touches anything - well you have a mess. So have a trash bag at hand you can drop gloves or paper towels into once they get the adhesive on them.

Did I mention this stuff is real sticky and it is easy to make a mess?

 

[ardvark]

Used Dicor for years at every dealership I worked at as well in our own service center. Pretty much the industry standard as it goes on easily, puddles and seals readily, and can be removed if necessary without making a mess. No need to smooth it. Just let it flow. It starts to set up almost immediately. Normally last for many years.

Have seen folks used a lot of different stuff and install vents a lot of different ways, but remember vents sometimes hit trees and have to be removed.

 

[shellback]

I like Dicor. Clean up the surfaces with alcohol before applying.

 

[Advmoto18]

Go with DICOR.

I use 4200 exclusively on my salt water fishing boat. I always spend more time cleaning up then applying the product. 4200 can be a real PITA to work with unless you have some helpful techniques in your kit; even then you might be prone to utter a cuss word or two (if so predisposed).

 

[PaulT]

I think of 4200 & 5200 more as marine adhesives with sealant properties than as primarily sealants. Both are great for their intended purpose but with some disadvantages when just sealant properties are needed.

Paul

 

[Wandering Sagebrush]

I think of 4200 & 5200 more as marine adhesives with sealant properties than as primarily sealants. Both are great for their intended purpose but with some disadvantages when just sealant properties are needed.
Paul

Paul’s is using euphemisms for both 4200 and 5200. While 4200 is just difficult to remove, 5200 is dang near impossible. Lots of cussing it on boat forums when folks are trying to remove a part that was attached and sealed with 5200.

 

[Mark G]

So, is it sticky and messy?
Thanks. I looked for the previous posts but couldn't find them.

 

[kmcintyre]

I had an interesting "experience" with Fantastic when my vent cracked. I'm not sure what brand you have but Fantastic gave me a lot of crap about a bad installation and that I didn't seal the vent correctly. I sent them a copy of the install guide and showed them that I sealed it just like the guide stated. They said they had a new guide now that had changed the sealing process. Huh? After that fact? They weren't going to cover it but instead said they would but with no warrantee on the new item. I also pointed out that the guide on their website showed exactly what I did. Go figure. Anyway, they insisted that the sealant should really flow over the top, over the screws and about 1" (I think) over the edges on to the camper. It's a continuous seal around the entire vent, along and over all the surfaces. Crazy. I'd take pictures too for any future "claims".

Oh, they also recommended Dicor.

 

[badtoytrd]

Just installed 2 Maxx Fans and I used Dicor self leveling. Worked great.

 

[ntsqd]

Paul’s is using euphemisms for both 4200 and 5200. While 4200 is just difficult to remove, 5200 is dang near impossible. Lots of cussing it on boat forums when folks are trying to remove a part that was attached and sealed with 5200.

Any of them use a heat gun? The very few times that I've needed to remove something bedded in 5200 on the advice of a friend who used to work in a chandlery I used a heat gun to first get it warm.

 

[Wandering Sagebrush]

Any of them use a heat gun? The very few times that I've needed to remove something bedded in 5200 on the advice of a friend who used to work in a chandlery I used a heat gun to first get it warm.

That I can’t answer, but I would assume so. The boating crowd is pretty savvy on the topic. The one application of 4200 I did on my boat has been there since 2005.

 

[Mark G]

Done. Used 5200 'cause it was at the big orange box. Took maybe an hour. Been putting it off for a year or so.
Thanks for all the advice.

 

[Bombsight]

I'd focus more on longevity of the product rather than ease of application. That said, 3M would be my choice.

 

[badtoytrd]

If you do ever need to remove the 5200 there is a product called Debond that works great.

 

[Mark G]

Thanks. I'll try to remember that. Now, what was it I had for breakfast?

I figure I'm good for another 18 years.