I'm not going to repeat some of the prep shots since they are the same as the earlier tank. I did, however, drop all provisions for inverted flight.

Here the stiffeners and drain flange are riveted on.

Same point in time as the last shot, showing the filler neck as well. Nothing interesting here.

Unlike last time, the rib riveting came out excellent! Here is the end bay prior to installing the vent line. I riveted these alone and kept the rivet tails and bucking bar clean for each rivet. I'm happy with the results this round, but I sure *hate* doing work over.

After each rib session, I would install the rear baffle with clecoes to ensure alignment.

Another shot of the end bay, but with a little less glare.

The end ribs, vent tube, capacitive senders, and nose support installed. I'm testing the senders to make sure there are no shorts and that a resistor between the skin and plate registers as expected. This is the final shot before closing up the baffle.

The baffle went in smoothly, the only hangup was the inboard z-bracket rivets. I learned on the second tank that the longeron yoke allows for using the squeezer. After cleaning up I installed the tank onto the spar to ensure alignment. The method detailed in the instructions of squeezing Proseal out of a bag worked very well in laying down a bead along the baffle/skin line of rivets.

Make sure you don't Proseal your tanks to the spars - check for any errant sealant if you mount them up to cure as I did.

Another shot of the inboard tank rib while the baffle installation cures.

The access plate installed - done!!!

I followed suggestions from the list and just Prosealed the cover on with no gasket using socket head cap screws in case the cover needs to be removed with the tank on the airplane.

I used a 1/8" NPT tap to allow the drain fitting to sit further in the wing. I left a small gap to the flange which ensures the pipe threads will seal tight. I was afraid of getting the threads too loose if I tried to go further.

Now I just need to wait for some fittings to start tank pressure testing, using the manometer method on several builder's web sites.

08/29/2002 - I am testing the tanks using a low pressure gauge and blowing into the drain fitting with the vent fitting capped and the fuel fitting plumbed to the gauge. I used Fuel Lube to get a good seal at the filler cap - I'll clean it up when done.

I'm testing with 0.75 psi which is quite easy to read on this gauge that ranges 0 to 3 psi. The gauge is from McMaster-Carr and is part number 4026K26.

No Leaks!!!

That was a little early, tank #2 had a leak at the outboard top rear baffle joint. I managed to get some thinned Proseal into the joint from the filler cap opening and no leaks anymore. Yes! I'll also seal up the exterior joint where the air was escaping as an added measure.

<back home next>