Return to the Tailcone!

After a lengthy time away from work on the tailcone, a window of opportunity arose to change that trend.  While awaiting some hardware for the fuselage wiring, I extracted the tailcone fairings from the Finish kit crate and returned to page 12-06 of the builder's manual.

The first order of business was to trim the top and bottom halves of the fairings along their scribe lines.  My method involved affixing painters tape along the edges of the scribe lines for better visibility.  Note in the second picture below, the #30 holes at the corners of the scribe lines to facilitate a smooth cut at the vertex of the obtuse angles formed between the scribe lines.

Next, the trusty Dremel tool with a fiberglass cutoff wheel was used to perform the actual trimming along the scribe lines, as shown below.  A light sanding with 220 grit was all that was needed to get pretty close to the final scribe lines.

A preliminary fit-up is made checking for alignment and overall accuracy of the tailcone shape and how it interfaces with the tailcone.

The eight, F-1294C tabs were positioned around the perimeter of the intersection of the upper and lower fairings and subsequently drilled and cleco'd into place.  An alignment notch on the edge of each tab made the process of vertical placement very easy to achieve a consistent location.  More painters tape was used to secure the halves of the fairings during the placement and drilling process.

 

The tabs were eventually moved to the inside of the fairings and had their upper holes match-drilled with the upper fairing and then the nutplates attached.

As the fairings were assembled into a single unit, the instructions called for a 1/32 - 1/16 inch relief between the joints.  Below is a before picture, showing a pretty tight fit.

Finally, the long slot was cut into the aft end of the lower fairing with the same cutting technique as previously described.

More shots of the finished product below.