Monday, November 25, 2013

F-1204Z Stiffeners & F-1268E Doublers Added

Yesterday’s session in the shop was brief, but fruitful. With the F-1276 fuselage bottom skin now attached onto the fuselage’s skeleton, a few more parts needed to be added prior to beginning riveting of the bottom skin. There are six L shaped F-1204Z stiffeners that bridge between the forward and aft center channel bulkheads … they are attached onto the F-1276 fuselage bottom skin from inside the fuselage by reaching through the inspection holes to position the stiffeners.
A small portion of one of the six L shaped F-1204Z Stiffeners can be seen by looking through the inspection holes.  The line of six Clecos below the inspection hole secures the F-1204Z stiffener in position for riveting.

The ten F-1268 A thru E doublers are somewhat thick metal plates attached onto the outside of the F-1276 fuselage bottom skin. They tie the fuselage’s ribs, center channel bulkheads and bottom skin together. The rivet holes in the F-1268 doublers were previously machine countersunk for the flush rivets being used on the RV-12 project. Subsequently, the underlying rivet holes were not dimpled in the F-1276 skin, center channel bulkheads, baggage or fuselage’s ribs. Of course, this took a little bit of time to figure out a few months ago … but the parts fit together perfectly without a screwup on my part, so all the advanced planning paid off.
 Placing Clecos into one of the F-1268 doublers.

Because the fuselage assembly is lying on its side, as opposed to upside down, decided it would be a good idea to spot check the parts alignment and after a few minor tweaks, all the rivet holes in every bulkhead received a Cleco ensuring the F-1276 bottom skin is in good alignment with the main structural components of the fuselage. In addition, the left and right F-1274 fuselage corner skins were placed in position and secured with Clecos for riveting.
W-1276 fuselage bottom skin in position along with F-1268 doublers, F-1204Z stiffeners and F-1274 corner skins ... all ready for riveting. Clecos were placed in all the bulkhead rivet holes to ensure good alignment.

Quite a few holes are to remain unriveted at this point in time, so they will be identified and marked during the next shop session and then the riveting of the bottom of the fuselage can begin.