Need advice on roofing seams

[danlott]

I put aluminum on the roof of the small teardrop I recently got. I used a metal brake to make nice folds for the seams. The problems is once I placed the pieces on the trailer the seams opened up due to the curve of the roof. I am looking for ideas on how to get the seams to lay flatter. I have tryed using a rubber hammer and a heavy roller to flatten the seams back out, but it is not working.

Here is a pictures of one of the seams.



I am considering using screws evenly spaced on the seams to hold them down. My only concern is putting extra holes in the roof.

What ideas do you guys have?

Dan

[M C Toyer]

Is the aluminum roof glued in place or could you remove it?

Was the edge of the bottom piece secured to a spar or just layed over the existing roof?

If not removeable I would seal the gap with self leveling gutter seal and leave it be. I think screws or pop rivets would make it look worse and cause it to pucker in between.

If it is removeable I might have a solution.

M C

[danlott]

It is glue down and the seams do not land on any spars. I think I could have got them to lay down flatter if they were on spars, but the backing is not solid enough to allow me to get any real pressure on the seams.

Dan

[Larry C]

How about an adhesive sealant injected into the gap, and then hold the gap closed with a long 2x4 placed on edge. strap the 2x4 ends to another 2x4 running under the trailer. Use wedges under the 2x4 in any area that is still raised.
Larry C

Maybe 3M 5100 or 5200 sealants or...

This stuff seams to get good reviews for strength:
http://www.acehardwareoutlet.com/productdetails.aspx?sku=8012940

[oicu812]

You said you used a brake to form the seam and it looks good, just needs to be "set down". Get a helper to back you up and take the bounce out of the seam as you

TAP it with a soft hammer. You can use wood,plastic or just about any flat surface that matches up to "back" or "Dolly" with. Even if you use screws you need to

set the lock or seam down. I'm assuming it's a pocket lock or seam. Hope that helps.

[danlott]

I am unable to get behind it to use a backer to set the seam. There is an plywood skin on the bottom of the spars that prevents me from accessing this area. So far the 3M sealant sounds like the best idea. How long does this sealant hold. It it similar to silcone or hopefully a whole lot better.

Dan

[Larry C]

I am unable to get behind it to use a backer to set the seam. There is an plywood skin on the bottom of the spars that prevents me from accessing this area. So far the 3M sealant sounds like the best idea. How long does this sealant hold. It it similar to silcone or hopefully a whole lot better.

Dan

Not sure what the "best" sealant/adhesive is, but some online research will probably find the answer. Even epoxy with the proper filler is used to hold metal deck fittings on boats. If you can push the seam closed by hand, I bet you will find something that will work as long as you can hold it tight till it cures.
Aluminum is going to expand and contract a lot, that's why I suggested the 3M products, but I am not sure they have the hold-down strength needed.
Good luck...

[oregonguy]

Seems to me like the material is bulging in the middle because of the pressure from the edges where the AL is fastened down.

Do the seams lay down with even steady pressure - then pop back up when pressure is removed? Or do they resist pressure, and try to stay puckered? If they lay flat while you apply pressure, then I could see adhesive working well. Otherwise I think you'll have to some kind of fastener....

If you are able to remove it, I think it would be best to connect the pieces permanently in a flat orientation, then re-skin. I know it seems like a lot of work in the wrong direction, but sometimes it's worth it. If you took the pieces off, laid them flat and got them just the way you like first, then put them back they would behave more. You might even be able to solder the pieces together, that would be the best... though it may discolor from the heat...worth a test on scrap material.

BTW, I like that textured AL. Looks great!

[S. Heisley]

It would be my guess that 3M 5200 would last the life of the teardrop. I understand that it is used a lot on boats.
I used some of that stuff and couldn't get the two pieces apart without literally ripping the board apart too!

Please be certain that your problem isn't from too much or too little material in that spot first, though. You can't undo it once it's done and dry and it's a bit messy to apply.
If you decide to use it, you can usually wipe off the excess that oozes out with a cloth dipped in mineral spirits, while the adhesive is still wet.

[aggie79]

It would be my guess that 3M 5200 would last the life of the teardrop. I understand that it is used a lot on boats.
I used some of that stuff and couldn't get the two pieces apart without literally ripping the board apart too!

Please be certain that your problem isn't from too much or too little material in that spot first, though. You can't undo it once it's done and dry and it's a bit messy to apply.
If you decide to use it, you can usually wipe off the excess that oozes out with a cloth dipped in mineral spirits, while the adhesive is still wet.

I used 3m 4200 instead of the 3m 5200, because the 4200 is supposed to be "removable". While 3M says it only has half of the strength of the the 5200, I could not rip apart two pieces of alumimum sheeting that I glued together as a test.

I'd recommend a combination of the techniques suggested. If possible loosen or remove your edge trim. If you can get to the back side of the plywood, use a dolly or something else solid to see if you can flatten the crimp. Then mask off both sides of the joint with blue painters tape. Apply a heavy bead 3m 5200 so that you can be sure that you get a good seal on the joint. Use a 2x4 to span the length of the joint and lightly clamp. I curved 2x4 works best. Place it with the bow to the middle of your teardrop with the ends up. Then clamp. If you can't find a curved 2x4 use wedges as Larry said. This will make an even clamping pressure. Remove the blue tape with the squeeze out and clean the remaining excess. (I used acetone.) Just be sure you don't glue your 2x4 to the top of your teardrop.

[linuxmanxxx]

Or just simply get some opaque 3M 4412N seam sealing tape and slap it on and forget about it.