You might notice we have jumped ahead in this log to where the installation of the winglets on to the wings begins. The wings have already been joined to the spar and the spar mounted on the fuselage which was one BIG task.  We are at an airport now, in a cold hangar in the middle of winter. I need to be out by a certain date and the clock is ticking…

This was three days work. I got a true centerline between the middle of the canard and the middle of the CS Spar wing assembly. As you see in Pic 3 I was a little out from my back seat centerline meaning the wings are about .2″ slightly to one side. Don’t tell anyone OK? As I’m using the canard and wings as my real datum points, the air molecules won’t know either.

I ended up with some welding wire stretched for my main line, tied at one end and weights on the other to pull it tight. My laser level line seemed too thick for this job. I located the BL 55.5 by just extending the square line I got from my center welding rod wire and measuring out 55.5″ using the square in Pic 2 and a long piece of aluminium box. Then measuring back from the back of the SC Spar which is at FS 125 to get my FS149.6 which I also used the aluminium bar as a straight edge reference.

Then I triangulated this on the front seat back point you see in pic 3 using a length of aluminium angle to check it was all good. This is all to establish WPRP (Wing Positioning Reference Point). I found I was 0.15″ out! OK I checked and rechecked as there is plenty of room for minor measurement errors using plumb bobs, rulers and bits of metal. The mark on the right wing was the exact distance from the TE it should be so I decided to call that one good. I’m still looking for the lost 0.15″

This Right WPRP will be used to set up the right winglet. Then I’ll match the left one using my Pic 3 reference point. Can you imagine anything more fun and challenging? OK…mainly challenging 😉

Canard center line

Wing center line

Mid point for reference