Monday, March 30, 2020

Fabric install on right side of fuselage (recovery)

We ran into a little problem when covering the right side of the fuselage with fabric.  Everything seemed to be going well, but after shrinking the fabric, we noticed that the top aluminum stringer was severely warped (scalloped) in the direction that the fabric was shrunk.  After looking into this in more detail, it appears that the mistake we made was to completely shrink the right-side fabric before covering the left side, which caused the top aluminum stringer to bend in the direction that it was pulled.  We could have just covered the left side in hopes that shrinking that side would pull everything back to normal, but we also figured that the odds of this actually working out right and looking good were pretty darn low.  Both sides really need to be shrunk at the same time so that there is no sideways force on the top stringer. 

With a heavy sigh, we decided a do-over was the right way to fix this.  We pulled out a couple of razor blades and cut out the entire piece of fabric on the right side, pulling off the fabric from the tubes where it was glued.  Doing this released the tension on the stringer, and it thankfully returned to its original (straight) shape.  We then cleaned up the glue, reapplied new glue, and started all over with a new sheet of fabric.  Overall, this went quicker than we expected and cost us a little over a week of work, plus about $90 in replacement fabric (including shipping which is not cheap).  Just chalk this one up as another learning experience.  The good thing is that the 2nd time around, we did a nicer job of covering around the window opening because we had already done it once and had some good experience.  Once the right fuselage fabric was glued down and the edges were ironed, we did a slight shrink, just enough to smooth it out so that we had a nice surface for attaching the left fuselage fabric, but not enough to cause the stringer to deform.  

Next, we applied more glue in preparation for installing the fabric on the left side of the fuselage.  Hours: 11.5

Removing the old fabric from the right side of the fuselage
New piece of fabric installed (fuselage is rotated, so Rt side is facing down in this pic)




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