I continued on the spar riveting today. Part of the spar requires AN3 bolts to attach angles to the spar. These holes are to be "tight fit" holes. To get these to be tight fit I first drill them to be just shy of the 3/16" dimension. I used a .1850" size drill. I then reamed to hole to the final .1875" dimension, first using a .1865" reamer, then finishing with the .1875" reamer. The heads of the bolts also needed to be oriented so that they are parallel with the spar caps. This allows for interference free fitting of both wing spars. The bolts were torqued to 30 inch-pounds of torque.
Reaming the hole for a "tight fit".
Holes are nice and smooth.
Bolt heads are aligned so that they are parallel to the spar cap.
