Where am I going wrong? W-709-L/R

On both of my main spars the 4th and 5th location from the wing tips do not line up. I am not sure if I am missing something, my spars (both not likely) or 4 ribs are not drilled right ( would have a different number). With all that said it must me be missing something. Both stars the out side holes are 1/2 inch off. Please help me! Very confused!!



Locations of the confusion on both spars.



Sorry about the photo. middle three holes line up. The outside two are 1/2 inch out.

BNut said:

On both of my main spars the 4th and 5th location from the wing tips do not line up. I am not sure if I am missing something, my spars (both not likely) or 4 ribs are not drilled right ( would have a different number). With all that said it must me be missing something. Both stars the out side holes are 1/2 inch off. Please help me! Very confused!!

Click to expand...

Check the plan narrative, seems to me with the 8 there was a note to match drill those holes.

But I could be thinking about something else.....I remember having to match drill some holes that were not there.

No notes on the drawing. W-708-1L/R do not have pre-drilled holes and have to be drilled.

Dwg 10A

Look at Dwg 10A front spar rear view. All the ribs are W-709 yet the top and bottom rivet locations at these two ribs is different. It has been awhile since I've done this but I also remember back drilling ribs thru the spar holes. Find it in your instructions. It is in there.

I think you abandon the top and bottom holes in the rib and back drill two new holes in the rib flange thru the spar holes. Do not drill any new holes in the spar.

I don't remember where this is noted but I think it is in the manual.

W-709 Ribs

Your spars are fine. My wing instructions dated 3/2/06 specifically references the need to drill new holes in these ribs on page 7-3, in the Assembling the Wing Skeleton section. See second paragraph that begins, "Drill the holes attaching . . ."

W-709 Rib Holes

BNut--

Here are a couple captures from the plans. Hope this helps. I was concerned when I first discovered this as well.

Chuck