Sealants

traveler1980

traveler1980

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Sep 4, 2019
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I know not to use silicone, but what sealants would you recommend for the seams where the fiberglass front/end caps join with the aluminum roof?

Also, is there a general purpose sealant that can be used for any roof penetrations

PO gave me this stuff -https://www.geocelusa.com/product/pro-flex-rv-flexible-sealant/

Thanks as always for any guidance you can provide!
 
I think the answer is Dicor b/c it works but also b/c it can be later removed and replaced, or recovered and another sealant will stick to it.

That's the problem with silicone, first it fails to stick permanently, then it is impossible to remove completely so that something else can stick. Nothing sticks to it. Terrible stuff, should be banned.
 
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Dicor is great on the roof. BUT, it is a self leveling sealant which means that it'll run off the sides quickly. For that you need a polyurethane seam sealer. I couldn't tell what your sample is made of but I expect that is the case. More investigation will tell the tale.
Our resident "Proffesional" body man, Sully (Todd Sullivan) up in Washington recommends 3M 08369 automotive seam sealer.
See HERE
 
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bdub said:
Dicor is great on the roof. BUT, it is a self leveling sealant which means that it'll run off the sides quickly. For that you need a polyurethane seam sealer. I couldn't tell what your sample is made of but I expect that is the case. More investigation will tell the tale.
Our resident "Proffesional" body man, Sully (Todd Sullivan) up in Washington recommends 3M 08369 automotive seam sealer.
See HERE
Click to expand...

They make a non-leveling Dicor, it's thick stuff, stays where you put it.
 
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I have used 3M 5200, which is a marine polyurethane adhesive/sealant. Don’t use it for stuff you want to take apart in the future.

Rick “not that I’ve eliminated my leaks...” Denney
 
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This is what I just got back from 3m Tech folks =


"Thank you for contacting 3M Automotive Aftermarkets.
3M (TM) 5200 Marine Adhesive Sealant will bond to aluminum and fiberglass. However, the 5200 is not UV resistant and would need to be painted. This product is a permanent product and you would have to also scuff the aluminum.
A better UV product would be 3M (TM) 4000UV, PN06580 which can also be used to fill the seam. Still will have to scuff the aluminum.
An automotive seam sealer would be 3M (TM) Urethane Seam Sealer, PN08367 that can be applied to bare metal or scuffed or primed metal. You can purchase at Napa or Carquest stores in your area.
Please let us know if you have any further questions."
 
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after reading WAY too many tech PDF's it seems to me the 3M (TM) 4000UV, PN06580 might be the best as its flexible, UV resistant, aluminum & fiberglass,,, and is designed for above & below the water line in boats - should be good for roof? What do you guys think?
 
Matt Colie said:
I do a lot of work on boats (other owners, I sold mine) so the kit has Debond in it. This stuff will loosen lots of things including 5200. Just be real careful with it. It won't eat epoxy, but it will lots of other things.

Matt
Click to expand...

Thanks for the info - what sort of things should I be careful with, with regards to our GMC's & related systems?
 
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