Fuel Tanks 5 (5.0 hrs)


Finally, a day in the shop where I left feeling like things are moving along and a lot was accomplished and I was much better about taking pictures today.

Today I started by machine countersinking the tank skins to fit the baffles.  These need to be countersunk instead of dimpled in order to allow the baffle to be easily installed and sealed.  It takes time to countersink all of those holes, as its an easy way to really mess up the skin.  20140101-212345.jpg

Here’s a good close up of the countersinking in progress. 20140101-212358.jpg

After machine countersinking was done, I disassembled the tanks and labeled all the parts.  I then turned my attention to the tank attachment angles and reinforcement plates.  I realized when I looked at the plans, that I had forgotten to trim off the excess (more than 2″) on the reinforcement plates, so that was the first task.20140101-212408.jpg

Next, I clamped the angles in place and drilled the three parts for rivets. 20140101-212416.jpg

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Now after doing this,  I’m pretty sure the reinforcement angle should be higher up to help seal the tank, but its too late now, so I’ll have to cross that bridge when I come to it.  Worst case scenario, I have plenty of scrap and can fabricate a replacement quickly. 20140101-212450.jpg

Time to move on to the capacitance fuel sensor I purchased.  Each tank has two plates that need to be installed and isolated from the structure.  I match drilled all four plates. 20140101-212459.jpg

I made the stiffeners ahead of time, but skipped final drilling them when the instructions called for it.  This was a good call.  I was able to trim the fuel sensor plates to fit the stiffeners at the same time as I did the final drilling.  Saved me a step or two. 20140101-212507.jpgThere is still a lot to do for the tanks before I can start sealing them up.  Next time I will try to compete the fuel sensor and access plates. As a side note, I bought a fly cutter on Amazon for $10.99.  It arrived today and here is a picture.  It can cut holes with diameters up to 6 inches.20140101-212335.jpg

 


About Peter

plbarrett.com | Certified Flight Instructor (Single & Multi-Engine, Instrument, and Advanced Ground) | Commercial Helicopter

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