To rivet, bond or tape? Exterior panels or interior or both?

[javajoe79]

I am in the planning stages of what to use and how to attach the interior and exterior panels on my hard sided popup camper build. I am leaning towards the 3M VHB tape for at least the interior. I am concerned about removing the outer panels for repair in the future so I was thinking of using rivets and a sealant like Acryl-R or sikkaflex.


Open to suggestions. Good point and bad points etc.. ???

 

[Maninga]

If you're wanting to remove the panels in the future, I wouldn't be using sikaflex. I stuck marine ply to a fibreglass panel and let it cure, ply preferred to delaminate rather than sikaflex letting go. See also
http://robgray.com/graynomad/wothahellizat/wot2/diaries/diary_19/index.php
I really like the testing in this thread.
http://www.expeditionportal.com/for...and-composite-panel-build-on-Dodge-2500/page7

Sika is great stuff to keep it together, but be able to realign if you need to move it across a little bit. Vhb tape is great too, but hard to take apart to move if mislaid

 

[mhiscox]

Sika is great stuff to keep it together, but be able to realign if you need to move it across a little bit. Vhb tape is great too, but hard to take apart to move if mislaid

Agreed . . . You're pretty much one and done with placement on the VHB tape. But it works pretty slick on the right job. Putting on the adhesion promoter first makes it work even better, in my experience.

 

[javajoe79]

Using that tape I was imagining I would be able to leave the backing on, put the panel in place then peel the backing out from under. Has anyone tried that?

 

[Haf-E]

If you used a VHB type tape with an inner foam layer - then it would be possible to "cut-off" the panel using thin wire or even dental floss to access the inside. The downsides of using VHB type tape is that there is more of a chance of the exterior being not totally sealed - so additional sealant might be required to ensure water proofing - with one of the adhesive caulk you wouldn't need to do this second step.

You should really read Rob Gray's build blog - he goes through all of this in detail and does it both ways (first VHB tape - then adhesive caulking).

I think you shouldn't plan to need access from the outside - it should be designed to allow inner access where required. Making the inner panels removable (i.e. screws) would be simpler.

 

[javajoe79]

Would you tape lap seams too? I imagine that would make a step the thickness of the foam.

 

[rayra]

100% silicone caulk. Most of the adhesion but has the relative ease for removability / replacement of whatever you mounted with it, and comes off easier. If you are talking about cosmetic panels and not structural stresses. Lot easier and more forgiving to work with, too.

 

[red EOD veteran]

If you're wanting to remove the panels in the future, I wouldn't be using sikaflex. I stuck marine ply to a fibreglass panel and let it cure, ply preferred to delaminate rather than sikaflex letting go. See also
http://robgray.com/graynomad/wothahellizat/wot2/diaries/diary_19/index.php
I really like the testing in this thread.
http://www.expeditionportal.com/for...and-composite-panel-build-on-Dodge-2500/page7

Sika is great stuff to keep it together, but be able to realign if you need to move it across a little bit. Vhb tape is great too, but hard to take apart to move if mislaid

Had no idea that the Sika 252 was that strong of a bond.

 

[javajoe79]

Which is cheaper, tape or sikkaflex?

 

[javajoe79]

How well does the tape insulate?

 

[Jeep]

Tapes or adhesives done properly will mean mechanical (cutting) the panel to remove. I used tape and Sika on my F-650 build 4 years and 50 000 kms with 25% of rough gravel later and very successful. Tape is very easy to use, adhesives a little more finicky, and cleanliness is Godliness! What reason would you want to access the inside of the wall? Design a wire chase, use a good insulation that won't decompose, and bond the panels solid, if you have to change a skin, cut it off, remove the adhesive, and bond a new one down. If you require access, put a door in, check out the marine and RV distributors for easy to mount access doors complete with frames. You will end up with a better build that does not loosen with normal use and provide failure a place to start. Using an inferior adhesive that will come apart easy, will do just that, create work you are trying to avoid by building a camper to start with, screws loosen, good rivets are awesome!
Cheers,
Mark.

 

[javajoe79]

Leaning towards the Sikaflex now that I have read up a bit on it. Now. Who has good pricing on a case of it?

 

[Jeep]

Cool build, if you are using the Sika, a good way of keeping the correct gap for the adhesive (you want .100" - .125") bond thickness is with little stick on polyurethane "bumpers". I buy them from McMaster Carr, cheap. You will also want to remove oxidation from the raw aluminum, scotch pad works, use Sika activator, and 206 primer on raw aluminum. It's necessary.

 

[javajoe79]

Good info. Thanks