Can't get simple STL file to mesh
 

My intention is to set-up an aerofoil (original I know!) using snappyHexMesh but I'm having no end of trouble. I've attached a very basic STL file which I've tried to import but I get the error:

--> FOAM FATAL ERROR:
Faces do not seem to be correct across coupled boundaries
Coupled face 9497282 on patch 0 allBoundary coords:4((-0.97 0.1 -0.09) (-0.97 0.1 -0.085) (-0.965 0.1 -0.085) (-0.965 0.1 -0.09)) has face area:2.5e-05 (coupled) neighbour face area differs:1.25e-05 to within tolerance 2.24499e-06

From function hexRef8::checkMesh()
in file polyTopoChange/polyTopoChange/hexRef8.C at line 4489.

FOAM aborting

I've had some success with a sphere imported from STL but no joy with this rough wing section.

Any help would be appreciated!