Yet another silkspan question...

Hi Guys,

The last silkspan thread mentioned the less-than-obvious grain direction on some of the modern stuff.

Well, I've noticed that what grain there is to the Sig medium that I have is across the width of the sheet as opposed to along it's length. The width of a sheet isn't enough to cover a wing panel, so it looks like the grain would have to go LE to TE instead of spanwise.

Of course, it was drummed into my head from an early age that the grain goes along the span, but does this slight difference in grain allow an exception? Should I go through it all and pick the best sheets? Should I get another cup of coffee and forget it???

Thanks!

God bless!

Mike,
just purely my opinion here - I really don't believe there is any preferred direction to the silkspan. I've had times when I almost convinced myself that I can see one - until I turned the sample 90 degrees....
Given what others said (and experienced) with silkspan recently, I would test it before applying to your airplane. Just build a simple frame out of balsa sticks, and try covering it as if it were a wing or tail. That can save you a lot of grief.

I can't always tell but I take a corner and rip or tare the paper parallel to a edge and then move 90 degrees and do the same parallel to the other edge. You can tell by the torn edge when you are tearing parallel to the grain and when you are going against the grain. With the grain is a cleaner edge than against.

Yes, grain direction is across the sheet in my Sig stuff. Tearing as described is very informative. If you have a fairly thick wing and cover with the grain chordwise the silkspan will really pull down between the ribs and look ugly. If you do one side one way and the other side with grain the other way it's likely to warp.

What about the Brodak stuff? does the grain go the long way in it?