Finally started installing fuel tank ribs with proseal and riveting. Vanity showed its ugly head so I was convinced to put 3M blue tape along proseal lines for that "clean" look. Outer rib including tip reinforcing doubler coverage equaled 50 grams white and 5 grams black proseal. The scale shows the weight including 14 grams for the plastic cup and wood mixer. I tried zeroing tare weight to include the cup, but when you remove the cup to help aid in depositing more white stuff, the digital scale forgets what the original tare weight was. So, I weighed a separate cup and stick and found it to be 14 grams. Therefore I knew I needed 69 grams on the scale to net out 55 grams proseal. Basically, I used all of it on the outer rib. So, roughly 5 more ribs will equal about another 275 grams proseal. We'll see how accurate that estimate was. You basically cannot get any proseal on the tank skin outboard of the 1st rib flanges because there is an aluminum strip that fits underneath the tank skin and the leading edge skin that holds the tank on with screws. That strip buts right up to the rib flange, so tape the tank skin right up to the flange. There is a little extra room on the skin at the very forward tip of the tank skin due to the rib flanges being shorter up there. Add more proseal in that area.
Clean mating surfaces with MEK, wiping over with a clean cloth or paper towel. Do same to the rib flange on outer and inner flange surfaces. Don't forget to MEK wipe the dimples too.
