Wing Contour?

Several years ago (1970 time frame) Wil Schumann did a re-contour of the H301 Libelle leading edge. It required a bit of build-up with balsa to the extent you're talking about. My father glued the balsa directly to the existing surface and roughed it to shape, slightly undersized on the templates.

The Bondo was then added to create the actual contour and was followed by a thin fiberglass layer, filler and paint.

It lasted until I bought the glider in 2015(!) and it's still there with no damage, other than a few chips that needed to be refilled.

I think if you check back in the archives you can find an article describing Wil's process.

Mike B.

One last point, most of the gliders that use the FX 67 series start with 67k170 17% thick, then at some point,
either from the root or the taper change at the aileron, transition to 67k150 15% thick at the tip.
This means that special care in needed to calculate the templates for intermediate stations.
My DG200 is 67k170 all the way. The 40 year old wing is very accurate still, something that cannot be said of
the PIK20 (one locally is 19% thick) the Mosquioto, and the Mini Nimbus, all of which seen to have suffered moulding errors.
As I recall, the reprofiled mentioned previously required special calculations for each individual aircraft.