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Bumpyroad's avatar
Bumpyroad
Explorer
May 16, 2014

OSI pro series H2U acrylic urethane sealant

Evergreen says to use a urethane caulk on the roof/sidewall seam. I have found the subject product and contacted Henkel who said it would work for that. before I drive 55 miles x2 tomorrow morning, has anybody used it and were the results satisfactory?
anybody have a suggestion for a better urethane sealant that I don't have to get a dozen tubes of to order it?
thanks,
bumpy
  • saw in one of the hits on the web that it is "similar to sikaflex". which has been recommended here.
    bumpy
  • my friend in the marine business says the same thing about 5200 being a great adhesive, claims you can "glue" a board to a fiberglass transom and after it cures/sets/whatever if you pound on the board it will rip the fiberglass apart.
    made my 110 mi round trip this am and got 3 tubes of the H2U, Henkel said that should work for my application.
    price was only about $5 a tube, since I think they sold it to me at the wholesalers price.
    I was a little afraid of using the 4200/5200 3M product unless I really had a leak, needed gluing something, etc.
    and yes, the 3M tube cautioned that once opened, even capping it back up didn't keep it from all setting up.
    thanks, will report on my success or lack thereof.
    bumpy
  • Bumpyroad wrote:
    is that those little 3 ounce tubes? couldn't find anything that fits into a caulking gun at lowes/HD.


    That's the full tubes- though it might be a matter of location, as we have a lot of boaters around here.
    Not sure if the link will work- 3M 5200
  • The OSI product has a huge amount of plasticity/ductility compared to the more conventional DAP or Lepage products. The technical data sheet shows an elongation rating of 1100%, that is a large number for any sealant. The PL and DAP urethanes will be much stiffer, almost rigid, as they're used more as an adhesive than a joint sealer.
  • 3M is expensive. But the big box hardware stores have alternatives. Tremco, DAP, Lepage and others:
    DAP
    Lepage
    Well, these are the canadian web sites ...
  • Bumpyroad wrote:
    is that those little 3 ounce tubes? couldn't find anything that fits into a caulking gun at lowes/HD. I might have misread that shipping cost of $10 for the tube. I talked to one supplier and their minimum shipping was $10.50 so it might have covered the 3 tubes? that I want.
    bumpy


    I have used the 3M 4000UV "Fast Cure" caulking on all my exterior surfaces and have even used one of the small tubes of the 5200. I think the permanent designation is for when you put it between two items. I think with some difficulty you should be able to get even the 5200 off as long as you are using it a a final surface sealant and NOT as an adhesive between two surfaces. If you use the 5200 or even the 4000 between two surfaces it's either permenant or extremely difficult to remove. Thus stick with buytl tape for the primary sealant where needed and then the caulking as the secondary sealant. HOWEVER, one thing to really watch is almost all the 3M Marine caulks are not UV stabilized/protected with the only one being the 3M 4000UV, both the 5200 and 4200 are not. You can get the 3M 5200 in the small tubes at some HDs. One thing is that once opened 3M recommends using the tube within a fairly short time frame like 2 or 3 days IIRC.

    All the 3M caulk I have used still looks great some 7 years later so it's some quality caulking for sure.

    Larry
  • is that those little 3 ounce tubes? couldn't find anything that fits into a caulking gun at lowes/HD. I might have misread that shipping cost of $10 for the tube. I talked to one supplier and their minimum shipping was $10.50 so it might have covered the 3 tubes? that I want.
    bumpy
  • Lowes carries the #M stuff- around $12/tube.
    A lot depends on whether Evergreen is using the sealant structurally- which Winnebago does. If so, I would get a specific brand from them.
  • Chris Bryant wrote:
    The gold standard urethane is pretty much 3M 5200 ( or 4200). I have no reason to not like OSI stuff, though, but I am unfamiliar with "acrylic urethane".


    yep, I considered the 3M product. I think the 5200 is permanent which I wouldn't want. will check out the 4200.


    just checked my tube of 4200. the label says medium strength, three dots permanent,, to removable. the center dot is checked so I guess it means you can get it off, but it will be a challenge.

    did another search and found a few "issues". the 4200 is about $20 a tube with $10 shipping?
    thanks,
    bumpy
  • The gold standard urethane is pretty much 3M 5200 ( or 4200). I have no reason to not like OSI stuff, though, but I am unfamiliar with "acrylic urethane".

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