I’m waiting for my new 8′ level to show up, so I’m holding up on working on the ailerons. In the mean time, the fuel tanks have been sitting for a good while now, and the sealant is good and set. Before I consider the tanks ready to go, I’m doing a pressure test on them to check for leaks.
This consists of plugging all the holes except one, putting a balloon over the last open hole, then pumping the tanks up with air. The balloon is there to prevent you from over-pressurizing the tank and doing damage to it. The balloon will pop long before the tank has problems.
Once the tank is pressurized and balloon inflated, I sprayed every rivet with a soap water solution. If air is seeping out, bubbles will form in the solution, showing you where the problem is. I did have one place I got bubbles, but luckily, it was just around the balloon itself. I wrapped a rubber band tightly around the stem of the balloon, and even that stopped. But hey, at least I know the solution works!
After checking both tanks, I decided mounting them to the wings would be the safest place for them. It’s quite tricky trying to lift the tanks up under the cradles and start bolts alone, but with the clever use of cardboard boxes, I managed. They are only held in with a few of the many bolts and screws they will eventually be secured by, they aren’t going anywhere for now.
How many Gallons of fuel will each tank hold? 100LL fuel?
Have you selected a powerplant yet? curious what the range will be?
Each tank will hold 30 gallons of 100LL. This will give me a range of about 1000 miles at 165kts or so.
The motor is going to be a Lycoming IO540.
Ed, how did you fuel tank leak testing end up?
Did you also test them filled up with fuel?
I´m building an RV-10 here in Germany and now at the stage of sealing up my tanks.
I love you nice build and am jealous at what time you managed to build yours :o)