Vans now get you to enlarge various holes in the ribs to accept different sizes of snap bushings. There is lots of debate in forums etc as to the merit of Vans’ choices here, but as I haven’t got a clear idea of all the wiring I decided to just follow the manual. Some ribs have holes in the correct place to enlarge, others have to have holes made according to dimensions in the manual. I found a clear head was needed to ensure the correct size hole was being made in the correct position on the correct rib! 

Page 14-05 shows the right wing, and each right rib has an upper system hole. I checked ahead in Section 19 (Wing wiring) and could not see a reason for all these holes. But as mentioned, not having a clear picture in mind, I decided to follow the manual.

The step drill worked just fine to enlarge the holes.

Deburring

Just when I thought I’d finished the rib deburring, all the system holes now needed attention, and there are lots of them … groan!