need advice

[jacques]

Last sunday, I did some flight with a good friend and is helicopter and it took some pictures. I noticed that my fabric on both tanks is strange....

What do you think? (and what do I have to do?)

sorry for the size of the pictures, it is to be more accurate

[jtpitkin06]

Jacques,

It appears the fabric did not get enough heat to shrink it tight.
It is loose over the tanks and the entire wing.
Compare your wing in flight to other Kitfox photos in flight.
You will notice the fabric should not balloon upward between
the ribs like yours is doing.

The loose fabric on your wing is a concern. Short of recovering
the wing I’m not sure how to shrink the fabric tight without
destroying your finish because heat will melt the coatings.

If you just want to attach the fabric to the tanks you can use MEK
to dissolve the coatings. Then use Polybrush thinned 50/50 to
reattach the fabric. Next, do the usual UV protection with
Polyspray and finally the color coat.

John Pitkin
Greenville, Texas

[jdmcbean]

Jacques,
This can be a serious flight safety issue. If you have a higher res pic please send it to me at john@kitfoxaircraft.com

If you have nay other pics please forward them as well.

Is the wing rib laced ?

[jacques]

Thanks all for your answer. I will wait for John (kitfox) advice.

I will also think about a new fabric on the wings or any other good solution.

[MotReklaw]

This picture give me reason to ask this question....

If fabric is shrunk in 90 plus temps, will it tend to be loose in cold weather?

[Av8r3400]

No. Once the fabric takes a set it will not "stretch" or "relax" back out with temperature.

[HighWing]

One additional comment. Over the wing tank while shrinking, the fiberglass can act as a heat sink and the temps absorbed by the fabric can be less than the temps felt by the free standng fabric. If the fabric is bonded to the tanks completely it is not an issue, but typically the tanks are not in the exact lalinement with the ribs and there will be areas that are not attached. That is part of the issue with Jacques wing fabric appearance.
Lowell

[cap01]

Jacques , noticed that you were resolving the loose fabric from another of your posts . Just curious what you were doing to remedy the condition ?

[jacques]

I have talked with the fabric specialist and he told me that the fabric
on the wing is very nice. In the tank aera also but it seems that the
glue on the tank is not doing its job on the fabric.

The leading edge on this parts is ok as on the root rib and the first rib after the tank. It is also well glued on the leading edge.

The problem is that the ttop of the tank is just below the top of ribs, so when the fabric is glued on the tank there is a small area close to both ribs were fabric do not contact with the tank.

He told me that I can still flying. Also, he told me that I have one day
to do something.

For exemple, if I change my tanks for ethanol able one's , just to
cut the fabric betwen the root rib and the first rib and put new one.

[cap01]

When I replace the tanks in my model IV that's what I did only two ribs further out . Since I was installing the larger tank, one rib was removed and the brace had to be relocated to the next bay outboard . Lowell is correct , the fabric is difficult to shrink correctly over the tank since the tank sucks the heat from the iron . Good luck with your fix