dle's Oz Build

[papabear]

Looking good dle, the big 40hr is getting nearer, excitement begins

[dcsfoto]

use preshrunk tapes for dark colors


David Kelm
912iS Big Bore Garmin G3X

[David47]

use preshrunk tapes for dark colors


David Kelm
912iS Big Bore Garmin G3X

Wish I'd known they existed before I covered !!. Too late now ..... and my grey is a darker grey (Polyfiber Federal Grey).

[aviator79]

I have Federal Grey on my airplane, and it doesn't strike me as particularly dark. My blue stripes are dark, and they cross all of my rib tapes. I brought the shrinkage concern up in some thread here or on facebook before I painted, and several people reported no trouble with tape shrinkage on darker trim colors. Time will tell. I'll probably park it outside in the Phoenix, AZ area a couple times a year, so maybe some wing covers would be a good investment.

[David47]

Brian, I’m not sure wing covers will solve any possible problem. From Lowell’s post, and it makes sense, it’s the buildup in temperature within the wing that could cause tape shrinking. These tapes shrink heaps when you apply the iron at 225F ... I know this because I had some wrinkles I needed to get rid of and couldn’t believe how much they shrunk. Like you say, I guess time will tell, so fingers crossed ....

[aviator79]

That heat has to come from radiant energy absorbed through the wing surface. So I am thinking a lighter-colored cover should reflect more heat and prevent the buildup.

[jiott]

I suppose this is one advantage of Oratex; if the finish tape shrinks it does not expose any non-uv protected fabric and no fine lines of a different color.

[Esser]

Personally, I think this is overblown. I haven't seen any tape shrinkage (doesn't mean it hasn't happened) 225deg is HOT like boil water hot. I have a completely black plane and I have never had my wing so hot in direct sun that if I dripped water on it, it would boil.

In fact having a black wing I was interested in seeing how hot my wing could get. On a hot July day in direct sunlight I put my wingtip down so no air could get out. The hottest it got was 53.8C or 128F. Even in Arizona etc I'd be surprised if you you could add a full 100deg to that

[David47]

Well, I’m not about to change my grey so I live with what happens, if indeed anything does happen. Heat reflecting covers would work and prevent buildup but I’m wondering if this is some kind of aging process on the tapes. They are, after all, applied with no shrink, and they are really just light weight fabric. Maybe over time with temperature variations/cycling they just naturally shrink when painted with heat retaining darker colours. I suspect though that if tape shrink was a serious problem with dark paint colours, poly fibre would have addressed this long ago. But then, maybe not ...

[aviator79]

It could be aging or that they shrink a small amount at temperatures below 225 deg F. In a little bit of poking around, I now find it very unlikely that fabric surface temperatures get that hot, even in Phoenix. Nonetheless, the phenomenon has been observed enough that the Poly Fiber manual contains a warning about it. I'm not going to worry any more about it until I have a reason to.