Gee, Doctor Sander, the patient looks like it contracted the pox. Nope, not the pox … just a fresh batch of thinly applied non-dyed microsphere filler.
While the application of microsphere filler cures overnight, my attention diverted back to working with the fuel tank. One of the last tasks to perform on the T-1204A-1 top tank skin is to drill the mounting holes for the mechanical fuel gauge. Actually, the holes are already drilled, but only to #30 ... they need to be enlarged to #19. The mechanical fuel gauge is set into the hole in the T-1204A-1 skin then the holes are drilled to #19 one at a time … after drilling each hole a screw and nut are to be used to hold positioning as the next hole is drilled.
Drilling through the mounting hole in the mechanical fuel gauge to enlarge the hole in the T-1204A-1 skin to #19.
The decision was made to apply a dollop of fuel tank sealant onto every rivet. It is a lot of extra work to coat every shop head with fuel tank sealant, but the DOG Aviation goal is to strive for leak free the first time. Batches of fuel tank sealant were mixed and packed into a syringe. The tip of the syringe was worked around every rivet getting a good coating on the metal around the base of the rivet then worked around the rivet a few times until the rivet was entirely coated. Also filled a couple of the corners in the fuel tank. with sealant.
A syringe procured from an animal supply house was used to apply the fuel tank sealant to all the rivet shop heads.
Inside of the fuel tank after all the rivets were coated with fuel tank sealant.