Polyurethane to glue aluminum skin???

[halfdome, Danny]

But ya can't make them drink!

Have you looked at this guys online album? I wouldn't use polyurethane on aluminum but I trust his judgement, he is quite a craftsman and he has to live with it. Danny

[Jiminsav]

I glued mine on with PL construction adhesive..it's ok..still stuck in most places.

[Ken Fincher]

Henry puts out a glue they recomend for glueing alum. to wood that works real well just be sure that you put down an even coat and be sure to have your alum. and everything ready to go because once the glue is trialed on you have to be quick to apply your alum & roll it down to work out any air bubbles & clamp it up.
I used the henry glue and it work excelent except I had one little section that I waited a little to long on were the glue did not adhere real good so I just put a couple of screws in.

( I did pick it up at Lowes, the depot does not stock it, at least here.)

update
The Adhesive is Henry 663 outdoor carpet adhesive.
( http://www.wwhenry.com/prod-663.htm )

The Sin City Teardropper.
Ken F.
( www.VegasTeardrop.com )

[PNWFTW]

So how did go?!

I'm preparing to buy and instal aluminum skin and will do anything to keep if smoof.

I have access to AL (0.025 thick I think) "roof skin" that is used on semi truck trailer roofs. I have been shown that is easy to dent. I hoped that gluing it firmly against the wood would offer more dent resistance, but looks like id be trading one problem in for another by that approach.

I guess I'll just float it though...

[noseoil]

I ran the numbers on mine & the aluminum skin on the roof (10' long sheet) expands about 0.20" in normal seasonal temperature changes. I live in the desert so it can & does go from about 25f in winter to 140f in the summer. I put my skins on at about 90f (a "cool" summer morning), as I thought it was about half way between cold & hot. In summer there's some oil canning on the sides, but they will shrink up at night again. In the winter it's tight.

[Tommy2tone_1999]

I used 3M 4200 marine adhesive just around the edges to make sure I didn't get and water infiltration. Other than that the aluminum floats.

[S. Heisley]

I used 3M 4200 marine adhesive just around the edges to make sure I didn't get and water infiltration. Other than that the aluminum floats.

That's probably among your best bets.

I tried many different polyurethane glues on some hinges that weren't being screwed to wood (metal to metal where I couldn't use screws either) and none of those glues held, even if they said they would.

3M products like 4200 & 5200 adhesives seem to work okay. I used it on my aluminum to wood weather stripping. (If you use 3M 5200, it'll tear the wood apart before it will let go. I think 4200 is a little gentler.) I ended up using 3M VHB tape on those hinges that I mentioned.