How do you pros add aluminum skin to a steel frame?

[weekender]

Long time lurker; first time poster here. I am wanting to build a trailer very similar to a Turtleback but I can’t seem to nail down how you guys attach the aluminum sheets onto the steel frame. Is it really just double sided tape from the auto industry? What about where the sides meet the top? How is that seem sealed up and look professional? I thought maybe just some steel angle around all those seems painted in a contrasting color with butyl tape under that. Thanks for any advice guys.

 

[john61ct]

Must prevent the different metals from making contact electrically or galvanic corrosion.

3M VHB tape is crazy strong, used for skinning skyscrapers.

Also modern sealant / adhesives have become fantastic, and eliminating all those holes is as well.

 

[opp]

aluminum sheets will oil can so if you can run a bead in the sheet that cuts down oil caning. Then try to float as much as you can. double sided tape can help some

 

[weekender]

aluminum sheets will oil can so if you can run a bead in the sheet that cuts down oil caning. Then try to float as much as you can. double sided tape can help some

What do you mean by oil caning? How do you float the sheets too? Thanks

 

[opp]

When aluminum get hot it expands . Has to go some where. The best way to deal with is a bead with a bead roller in the panel. floating the sheet. the center can move just the outer part tide down. The bead is the best make skin stronger

 

[john61ct]

OK, so start by googling "bead roller".

Obviously would need some sort of a machine shop (fabricator?) with those sort of tools.

 

[john61ct]

Next to figure out the meaning of "floating" in this context.

Not sure how tides come into it?

 

[john61ct]

Yes understand the beading now.

Using an adhesive / sealant that is superstrong, but stays very flexible (elongation spec) should help rather than welding or mechanical connectors.

3M 5200 might be a good fit, but would need to wreck the sheeting to undo it once cured. Sikaflex 292 similar.

4200 is more reversible, but still very strong, similar to Sikaflex 291.

Surface prep and ambient temps are critical to success with all these.

So if there is foam slabs between the framing, I guess should not be attached to the metal skin? Or maybe that would help keep it flat, like laminating composite panels. . .

 

[opp]

Man I should be shot missed auto correct ( tides) , So if there is foam slabs between the framing I guess should not be attached to the metal skin? Or maybe that would help keep it flat, like laminating composite panels. . . in what world is foam stronger than aluminum

 

[weekender]

I checked Harbor Fright’s website and they don’t have a bead roller. Apparently at one point in time they did for around $100. Saw some on eBay in the $150ish range. I wonder how much weight I would save if I just used steel instead of aluminum hmmm.

 

[weekender]

16 gauge steel is 2.5lbs per square foot and aluminum is .89lbs in the same comparable thickness. Yikes

 

[opp]

16 gauge steel will oil can Do you own a router ? you can make you own bead using a cove bit on some MDF plywood .
I have made louvers for cars this way .The oil can is not that big of deal . But if it has to be perfect . That why I go with glue and go kits that way I can mess up a lot a lot and it will come out tcefrep.

 

[weekender]

Nothing I do is perfect. I do have a router. I’ll google some videos of that trick.

 

[john61ct]

Not saying foam is stronger, but the combo laminated might be more stable with temp swings

 

[ottsville]

Have you looked at sandwiched aluminum sign panels?