Aluminum roofing question

[Scott L]

How fair does the roof need to be before skinning it with aluminum?

Since I'm going to skin the roof of my teardrop with aluminum, I built it with 1/8" luan. Yesterday, as I was working on the hatch, I noticed that the luan isn't very fair. It has dips and depressions and is somewhat wavy. Should I get some bondo or something and make it fair before putting the aluminum on?

Thanks,
Scott

[Classic Finn]

How fair does the roof need to be before skinning it with aluminum?

Since I'm going to skin the roof of my teardrop with aluminum, I built it with 1/8" luan. Yesterday, as I was working on the hatch, I noticed that the luan isn't very fair. It has dips and depressions and is somewhat wavy. Should I get some bondo or something and make it fair before putting the aluminum on?

Thanks,
Scott

Greetings Scott

I think others will have different views but if it was me, I would try to get all the major dips or or holes smooth as possible.. however I think it also depends on what gauge aluminum you use..the aluminum wil cover up many of your irregularities though.

But thats only my idea on it..

Best regards
Classic Finn

[halfdome, Danny]

I'll have to agree with Heikki. Once you attach your aluminum there's no going back and fixing imperfections in your substrate (Luan). I did 2 layers of 1/8" Baltic Birch and bondo'ed between them and the top one came out smooth enough to cover with .040 aluminum. It may seem like an over kill to some but like I said before there's no going back to fix any imperfections. I don't like "I should have". Danny

[Jiminsav]

yeah man....make it smooth as you can..check for ribs pushing the front curve out..make a template like nascar if you have too, but don't cover it till it's like you want it to look like in your minds eye.