ROOF seams and sealing by Cowcharge

Looks good Cowcharge! I think you're right about Eternabond, prep and rolling. It also depends on the weather. Horrible Hot desert type climes don't mix well with much of anything.

Another thought: not sure I would use Eternabond around the vent. They do eventually need repair. The sticky part of Eternabond is not fun to remove...

Here's some things I've learned using Eternabond tape. It comes with really good instructions, so it's easy to use if you're careful, but some stuff that you should know isn't in the instructions.

Thoroughly clean the roof for miles around the seam (but don't leave any water or solvents in the cracks of the seam), dust the trees, give the neighborhood squirrels a bath, and wash your hands as clean as you can get 'em before you pick up the roll of tape. The tape is kind of sticky/rubbery on the surface too, and dirty fingerprints stay there.

It has a clear plastic backing tape covering the adhesive. What I do is lay it out along the seam with the backing still on, and cut it so it overhangs each end by about an inch, so it will wrap under the J-rail and cover every inch of the roof seam. The edges will stick to the roof even with the backing on, so you can't really slide it around much. It also comes with two waxy paper circles that cover the sides of the roll. Only take them off to unroll the tape right before you cut it, then put the circles back on and put the roll away. If you set the roll down on anything without the paper side covers, it'll stick.
If you don't catch it quick, I'm not sure you could get it off the roof.

It's very stretchy and rubbery and sticks hard, so you have to put it in the right place the first try. Peeling it back off is possible only if you haven't pressed it down in the slightest yet. And I mean slightest. A spot the size of a dime will stretch that tape out of shape if you try to pull it off.

Once the tape is cut and lying on the seam, I work a foot or so at a time, peeling and sticking it down. I use my right hand to hold up the point where the backing is folded back, and my left hand to slide from the last stuck-down part to my right hand, only on the raised center of the seam, which is covered by about a third of the tape. If you're careful going from the end of the last section to the backing tape, you can get it all to stick to the center without trapping any air bubbles, while leaving the outer two-thirds of the tape unstuck. The instructions tell you how to handle bubbles if you get them. The important thing is to get the center stuck down enough not to move, but leave the rest of tape loose enough to move. You can't keep the outer parts from touching, but if they only touch, they can still move a bit in the next step.

Here's the hard part to describe. Once that foot of center is down, I take the fingertips of both hands like I'm trying to hang on to one side of the seam for dear life while someone tows me down the road, and using just the very tips of all eight fingers at once (practically just the nails), I tuck the tape into the corner between the raised part and the rest of the roof. Just try to get the tape tightly wrapped over the edge of the raised center and tucked tightly into the corner at the bottom, without pressing the outer thirds of the tape down. If only the higher center of the tape is stuck down and the lower sides of the tape are still loose, you can pull the tape closer to the center, rather than stretching it into the corner, which might let it "cut the corner" and leave a little triangular tunnel underneath the length of the tape. If all that gibberish makes sense.

Once it's tight in the corner on one side, I smooth that side of the tape away from the center out to the edge, being careful not to get any wrinkles in it. If you're careful you can get it down without any wrinkles or air bubbles, but again, they can be fixed, so don't try to pull it back off. Then I tuck and smooth the other side.

Then I start over with the next foot or so, peeling the backing off underneath, lifting and stretching, and sticking it down. Then the next foot, and so on. A little wrinkle forms across the width of the tape on every segment, right where the backing curls under, but stretching the next foot pulls it out. If you pull too hard, you'll see it wrinkle lengthwise.

When I reach the other end, I fold the extra at the ends down over the side of the camper and press them down tight.

Once the whole length of tape has been pressed down with fairly good hand pressure again, enough to make sure it's down everywhere and not going to move, I take the roller and go over it good. I roll the whole length of the top first, then one side, then the other side, making sure to get down in the corner good. And that's it!

It's wicked sticky stuff, ayuh. But in every other way, it's very flexible and forgiving. It'll bend 'n' stretch like you wish masking tape would do when you're trying to mask a curve on a paint job.

Never GOOP the roof! If your seams are good, you won't need to seal them. Personally, Eternabond is a last resort on a vintage trailer. It will stick too GOOD.

With a new roof, the seams should be factory sealed with no further action needed. New putty is needed under the edge trim/J rails.

Our Corvette has a new roof, no sealant on the seams, no leaks. I would leave it alone.

Of course, every trailer should be inspected yearly for damage. There's always the possibility a SMALL amount of sealant may be necessary.

The problem with using any kind of sealant to repair a roof leak is this. When traveling, the roof ripples and vibrates from the wind. So it is in constant motion. Once the sealant starts to harden or dry out it cracks or separates from the skin. Shrinking also occurs. Not the sealant itself, but the metal. As Steve Loomis pointed out in one of my Metal Skin videos, as the metal skin heats up and cools down, it shrinks and expands. After a little time with this happening, the sealant is separated from the skin itself causing the leak to reappear.

Now you know the rest of the story... 

Hey.......have you installed the new roof yet? Was curious to know if the video was up yet........