Wednesday, July 21, 2010

I knew this would happen

Remember how I needed to order the fuel nipple that would pass fuel through the firewall and into the back of the gascolator because I had failed to do a complete enough inventory? Ans remember how I was missing two of the 3/8" sleeves to hold nuts onto flared 3/8" tube? Well, I knew it would turn out that these parts were, in fact, included in the kit and I had done all of that ordering of replacement bits and pieces for naught.  Well, I was right, and I was wrong. I found the sleeves.

The nipple has not yet been found, but its replacement finally arrived from Van's. You may also remember that I had attempted to order the nipple from Aircraft Spruce, but ended up getting the wrong size. Why, then, you ask, did you not just order it from Van's in the first place? Well, consider this: shipping from Aircraft Spruce was $1.28. Shipping from Van's was $8.50. They annoy me this way. Van's typically provides top-notch customer service, but they have yet to provide customer-friendly tools to allow the purchaser to make an informed decision regarding shipping method. In my opinion, that is something they could and should fix.

Do I seem a little crabby tonight? Eh, the paying job has a way of wearing me down towards the middle of the week. Some days go smoothly, others are pockmarked with unwanted interruptions, meetings that inevitably dump ever more work onto my crowded platter, and a crappy commute both ways. Two out of three, today. One bright point though was my sharing of an original, piquant, and pithy insight in one of the meetings: "The fact that I have a hidden agenda may make me duplicitous, but it does not follow that it makes me wrong." I don't think it worked, though. I ended up with the additional work anyway.

Nothing more relaxing than twisting a nipple, I figure, so I treated myself to a little shop time. You may recall that the hole that I drilled for the gascolator looked like it might have been a little off-center. Well, it was. It only took a little filing to get it rounded out to where it needed to be. Two bolts later, the gascolator was attached.

That was the final step in the outgoing fuel system. Now for the return line! The return line starts (well, the fabrication of it starts) at the fuel tank, follows the supply line around a little bit, and branches away to feed down to the bulkhead fitting that I enjoyed installing last Saturday. Because it is only 1/4" diameter tubing, it's a little tricky to get it to follow the 3/8" diameter around turns because the turn radius is a bit tighter. Or so it seemed to me; it's just as likely that I screwed up the math again. Either way, I found that the best thing to do was to be very careful to get the separation distance correct where the two tubes make their vertical climb up to where the fuel tank will be and just eyeball the rest. The two tubes will be clamped together for part of their run and I found it quite helpful to clamp them together early in the process to help maintain the required 1 5/8" separation.

The clamps are quite simple: they're just hose clamp and rubber tube.

I used the scrap of paper with the two Sharpie(tm) marks to set the spacing between the vertical tubes and used the first clamp to hold them in place. Then I just made the bends needed to shape the return tube to the path of the supply line. The hardest part was figuring out the bend required to angle the return line down to attach to the bulkhead fitting. I gave myself a few extra inches of tube to work with, and through a process of trial and error that saw the paired tubes in and out of the fuselage a dozen times, I finally got the length right, the tube flared (with the nut and sleeve on it!!), and the assembly installed for what will hopefully be the last time.

And now it's time for dinner!

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