Making good progress on the spars, all four are assembled except for the plywood. Since I need to drill holes on the spars for the root and strut fittings I decided to make them now so I can match drill the holes.
There are eight root and eight strut fittings made from RS-100. The only difference between the two is the location of the center hole.
I started by marking the location of all the holes and drilling small pilot holes.
These are used in pairs so it is important that the holes line up perfectly. On two of them I drilled one hole to it’s final size of 1/4″.
Next I used the pilot drill bit and a 1/4″ bolt to line up the two parts.
Then drilled the hole on the opposite side and put a 1/4″ bolt in that hole.
Then drilled the middle hole, all three match perfectly.
All eight root fittings are completed. Need to make the eight strut fittings and the aileron bearing brackets before I can start wing assembly.