Monday, May 9, 2016

Section: 13
Hours: 2

Today I double checked my work and reread the construction manual in preparation for joining the leading edge pieces to the spar. When I trial fitted the outboard leading edge assemblies, I noticed I had overlooked breaking the joining edges. Since the holes were already dimpled, I couldn't use my edge break roller. I manually used my duck bills and put a slight break along all the edges.

In looking over the rivet call outs, I saw the note about holes for the tie down lugs. I got out the step drill and enlarged the already drilled tie down holes to 3/8".

Next I noticed there were some empty holes in the spar. On further investigation I realized I had overlooked some nut plates that were called out back in chapter 13. They are all the way out at the end of the spar and were off to the side of one of the manual drawings. I counter sank the holes and riveted in the nut plates. It was a little more work moving the spar around now that the ribs, sub spar and top skins are attached.

Section: 16
Hours: 2.5

I felt pretty confident that the outboard leading edge assemblies were ready for attaching so I moved on to finishing up the tanks. I counter sank the holes at the inboard side of the tanks using the #8 counter sink and finishing up with the #30 because the #8 would not go all the way to the final depth.

I hadn't done the pressure test yet to check for leaks, so I rounded up all the plugs, drains, strainers, fuel caps, balloons, air valve, thread sealant and a bicycle pump and went at it.

You have to insert plugs in the remaining open holes. I spent some time researching the proper torque values and what sealant to use. After perusing chapter 5 and reading several threads on Van's Airfare it looks like you apply thread sealant and then finger tighten the plugs. Then you tighten another 1.5 to 2 revolutions with the wrench. Same thing for the fuel strainer and the fuel drain plug. Here's the sealant that I bought at the local auto parts store.

I found the gas cap was a little loose, so I tightened the nut on the inside of the cap until I felt a little more force on the locking arm when closing it up. Then I taped over the gas cap with clear packing tape to fully seal it.

Here I've pumped air into the tank just enough to inflate the balloon that is tied to the vent line. The balloon stays inflated for about an hour and then slowly deflates, so I have a leak somewhere. Tomorrow I'll get out the soapy water and spray the tank down to look for leaks. Right now I suspect the balloon is leaking, but the soap will tell.


No comments:

Post a Comment