The last task for the new leading edge was to locate the rivet holes on the lower side and rivet it on. When I made the skin the old one measured 14 7/8" but, I made the new 15" because one of the holes was to close to the edge. I should have written it in red on the plastic protector on the skin. I got everything in position and the edge seemed to be in the right place so I aligned the old skin with it and punched the holes. Bad plan, the holes were off by 1/8". In the past I've pulled the skin tight and carefully located 3 holes to align the old skin with before duplicating the holes.
.
I should have done that here. As a result I removed the new skin and made a new one, again. One thing I did differently was to leave the short (lower) side 3" long and clamp it to the form board. I then pulled the skin around the tube with straps and boards as before and trimmed off the 3" after forming. It made the 2 halves closer in length and much easier to work with. I also made this one using 1"
pvc instead of 1-1/4" as I first tried. It fit perfect.
.
.
.
.
.
To match the bottom holes better I clamped the skin down using straps and 2/2's to hold it tight to the ribs. I also found it fit straighter with a block of wood holding the leading edge out at the last rib at the tip. The rib is just not strong enough to pull against and the skin will pull in at the tip and bulge between the ribs along the bottom edge. I had to shim it to a tight fit and the skin came out straight.
.
.
.
.
.
.
.
.
.
.
Before pulling the skin around I carefully drew
centerlines through the holes and made pencil marks on the ribs 1" and 2" from the hole center. This makes it easy to locate the hole
centerline parallel to the spar. Once the skin was pulled tight I marked the
centerline on a piece of tape at each rib. This made it easy to line up the last holes on the old skin and duplicate the holes as before.
.
.
.
.
.
While riveting the bottom rivets I placed a strap next to each rib to hold the skins tight so all the holes lined up better. All but the rivet closest to the leading edge were able to be
squeezed.
.
.
.
.
.
.
Installing this new skin went better than the first one, but it was not my goal to get better at this, just get it done. It is done. When the snow finally melts I'll get it outside and finish some light cleaning on the rest of the wing and prime it before covering. I worried that all this work would leave the wing more difficult to trammel but, it was closer to square than the left wing. It also now has the heavier drag wires required by the AD.
The last task for the new leading edge was to locate the rivet holes on the lower side and rivet it on. When I made the skin the old one measured 14 7/8" but, I made the new 15" because one of the holes was to close to the edge. I should have written it in red on the plastic protector on the skin. I got everything in position and the edge seemed to be in the right place so I aligned the old skin with it and punched the holes. Bad plan, the holes were off by 1/8". In the past I've pulled the skin tight and carefully located 3 holes to align the old skin with before duplicating the holes.
.
I should have done that here. As a result I removed the new skin and made a new one, again. One thing I did differently was to leave the short (lower) side 3" long and clamp it to the form board. I then pulled the skin around the tube with straps and boards as before and trimmed off the 3" after forming. It made the 2 halves closer in length and much easier to work with. I also made this one using 1" pvc instead of 1-1/4" as I first tried. It fit perfect.
.
.
.
.
.
To match the bottom holes better I clamped the skin down using straps and 2/2's to hold it tight to the ribs. I also found it fit straighter with a block of wood holding the leading edge out at the last rib at the tip. The rib is just not strong enough to pull against and the skin will pull in at the tip and bulge between the ribs along the bottom edge. I had to shim it to a tight fit and the skin came out straight.
.
.
.
.
.
.
.
.
.
.
Before pulling the skin around I carefully drew centerlines through the holes and made pencil marks on the ribs 1" and 2" from the hole center. This makes it easy to locate the hole centerline parallel to the spar. Once the skin was pulled tight I marked the centerline on a piece of tape at each rib. This made it easy to line up the last holes on the old skin and duplicate the holes as before.
.
.
.
.
.
While riveting the bottom rivets I placed a strap next to each rib to hold the skins tight so all the holes lined up better. All but the rivet closest to the leading edge were able to be squeezed.
.
.
.
.
.
.
Installing this new skin went better than the first one, but it was not my goal to get better at this, just get it done. It is done. When the snow finally melts I'll get it outside and finish some light cleaning on the rest of the wing and prime it before covering. I worried that all this work would leave the wing more difficult to trammel but, it was closer to square than the left wing. It also now has the heavier drag wires required by the AD.
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