Started on the cowling connection strips, these had to be dimpled. These holes were pre-drilled to 3.2mm but the dimpling enlarged these holes to around 3.7mm. Therefore we chose a dimple size which was able to countersink a 4mm rivet, dimpled the holes and afterwards drilled all the holes to 4mm.
After everything was dimpled and cleco'ed in place, we drilled out the holes to 4 mm and started riveting the mounting strips to the fuselage. We read on Craig's Sling 4 blogpost that he advised to start from the top and work your way down to the bottom so we did that. We used these little clamps to press the plates together, which helped with preventing bulging and made sure that the plates were riveted together tightly. On the bottom part we noticed that the skin still kept bulging and didn't get completely smooth compared to the top part. For now, we accepted it and maybe we'll use a filler to make it completely smooth before painting.
Builders of today:
Drilling out the misaligned holes in the main spar
This post is from Phoenix FS