Monday, 26 November 2007

Fabric Removal - The Fuselage

Having removed the skylight, I started to tackle the main part of the fuselage by removing the fabric. The hope is that this will be removed in one piece (or as near as) so that I can use the fabric as a template later on when recovering. This may sound unnecessary but I forgot to measure up where the rudder cables exit the fuselage before cutting the fabric off, but I should still be able to get a fairly accurate measurement from the remains.

The tools required were just a Stanley knife, stout gloves and a mask. Razorback, being glass fiber is nasty stuff, and I had already got a rash from cutting small bits of fabric when transporting the aircraft to the workshop (once bitten, twice shy).

I started by cutting down the center of the fuselage top deck and then peeling the fabric off the sides, taking care not to scratch any of the tubes underneath with the knife blade.

An initial inspection of the tubing revealed very little , if any, corrosion on the upper longerons but the lower longerons are covered in dirt and grime accumulated over the years so I won't be able to see the corrosion until this is all removed and the tubes cleaned.

One interesting point I noticed was a kink in the starboard top longeron at one of the weld clusters which isn't mirrored on the port side. I've been told this may be due to weld 'shrinkage' or due to a deliberate outward curve on the tubes which will disappear when the fabric is shrunk on. If anyone else has any thoughts, let me know.

I wasn't surprised to find that spaces between the inner and outer fabric layers above the doors and around the D windows had been filled with an expanding foam; I already knew it was there, but I was keen to remove it and check that it hadn't trapped any moisture, potentially causing corrosion in the tubing.

So far it seems I may have gotten away with no corrosion in these areas.

What was surprising was the condition of the woodwork around the doors and skylight frame. Once it is all cleaned up a lot of it may be re-usable.

The D window frames are substantial and my plan at the moment is to replace them with smaller D windows. The top of the window will be in line with the top of the door, while the bottom edge will follow the line of the diagonal tube which runs from the back of the seat to the roof.

I still have the fabric around the port side door and window to remove and I need to remove the fabric from the bottom of the fuselage. When that is complete I can finish removing the boot cowl, clean up the fuselage tubes, inspect them for obvious corrosion and then look at stripping and inspecting the wings.

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