The original plan was to use the digital level to establish the angles … but it was quickly realized that due to the flexi nature of the mouth of the tail cone that was not going to be a good option. Finally settled on using the digital level to mark the required angles onto a piece of cardboard, and then carefully cut out the pieces from the cardboard to use as a gauge.
Pieces of cardboard cut to be used as angle
gauges for bending the tabs on the tail cone per the plans.
Technical difficulties: This paragraph will only apply to those who have dimpled the tail cone for flush rivets. The plans suggest bending the tabs on the tail cone using the same bending tool fabricated for bending the closeout for the wings. This tool will not work on the DOG Aviation RV-12 because the rivet holes in the tabs have already been dimpled for flush rivets. During the winter I gave this issue some thought and came up with what seems like an easy and eloquent solution to the problem. Another bending tool was fabricated with a much wider slot. A thick piece of aluminum flat bar 3/4" wide was cut and a hole carefully drilled and machine countersunk to create a spacer. The location of the countersink is such that when the spacer is placed under the dimples on the tail cone’s tabs, the spacer sits flush with the outer edge of the tabs. The slot cut into the bending tool is the same 9/16" depth as the original bending tool however the throat is opened up so when the metal spacer with the countersink is sitting under a dimple, the tool barely slides over the tabs on the tail cone. This worked out great for bending the tabs … so for those that have dimpled for flush rivets this is a viable option for bending the tabs on the tail cone.
Modified bending tool with a mouth just wide enough to accommodate the thickness of the tail cone tab and the countersunk bar stock spacer.
Using the modified bending tool is easy … just place bar stock spacer under the dimple in the tab. This creates a flat surface for the bending tool to work with. Next slide the bending tool over the tab and spacer then begin bending to the desired angle. Zooming in on the photo below one can see the countersunk spacer under the tab being bent.
Using the modified bending tool with countersunk
bar stock spacer to bend one of the tail cones tabs.
By the time the modified bending tool and spacer was fabricated, didn’t quite have enough time to finish bending all the tabs … so will finish up that task during the next work session.