06/13/2018 Horizontal Stabilizer – Cleco Left Side Skeleton (1.5 Hour)

Today I started the section in the plan that’s called “Drilling the horizontal stabilizer”, which is essentially putting the skins onto the skeleton and drill everything to final size.

First I need to mark and drill two pilot holes in HS-00006 the most inner front rib for attaching it to spar later. I very carefully marked the center line and center punched the spot before drilling, the centerline is only 9/32 inch to the edge so there’s not much margin for error to maintain edge distance of 2 times the diameter of the rivet (AN470AD4-6 rivet has 4/32 diameter).

Then I marked the center line on HS-00005 most inner back rib. The flange on HS-00005 is just a little more than 1/32 inch longer than HS-00006 so I measured and drew the line very carefully again.

Last I picked out the left side of the components and clecoed them together. Then I enlarged the attachment holes to #30 size, removed clecoes, deburred and clecoed them together again. Next work session I’ll finally get to put the skin onto the skeleton and finally have something that shapes like an airfoil!