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The Center Spar is installed, meaning that all the holes are drilled and it all fits. This post includes the Center Spar Installation Template I posted earlier as an idea. Scroll to the bottom for the new stuff. I added some additional detail to drilling the spar bolt hole.
Next I set the proper width for the wing spar using the new uprights as shims.
Measured the edge distance for the Center Spar front rivet line.
I decided to use a 30 pitch instead of the 40 pitch on the Upgrade drawing. This will allow me to place the new rivets between the existing holes that were set at a 30 pitch. Should have made the Center line a No Rivet zone and back drilled after installing.
Template ready to be drilled, except I should have waited to drill the new center line/doubler holes.
But I came up with a solution, another template.
Cleco and drill the four missing holes.
Measure 84 times, drill once. Verified that the Wing Spar will fit just right.
Drilled a couple of holes on each end to lock the Center Spar in place.
The competed template ready to be installed. I rounded the corners and the edges to make installation easier. I will have to remove to deburr and corrosion protect.
Template installed using the existing holes for the rear Center Spar.
Back drilled every other hole on the front Center Spar and front doubler rivet line. Time to install the Center Spar for another trial fit.
A view from the bottom.
Success!! This was way to easy ;-)
I need to finish drilling the remaining holes and then I will remove the Center Spar and fit the Front Wing Uprights using the procedure I posted earlier. That's my story.
Trimmed 6B10-4 to make installation easier.
Test fit the Front Wing Upright. I put a slight bend in the flange to compensate for the fuselage.
Setup is similar to the Spar Upright. I measured up 30mm and bent approximately 4 degrees.
Here are my reference points marking the top of the Center Spar and the existing holes in the fuselage. The horizontal lines are machining marks.
Set my rivet line at 12.5mm and the rivet pitch to miss the existing holes.
To the Drill Press. Clamped a block so I could slide the Upright across and just have to hit the mark.
Clamped the old Uprights to set the reference lines
Reference lines for the rivets.
Next I setup and drilled the rivet line.
Verified my edge distance.
Reinstalled the Center Spar to drill the fuselage sides.
But first, need to make sure I have the right gap for the Wing Spar, I used the Wing Jig, and then drilled.
I drilled the holes above the Center Spar first.
And then removed the Center Spar to drill the remaining holes in the fuselage.
Time to take apart the Center Spar and drill the 5/16" spar bolt holes through the Front Wing Uprights.
This should look familiar. I had to modify the drill guide base, cut off about 15mm to use on the upper Spar Cap. After clamping I turned the drill bit over and spun it to mark the center on the Front Wing Uprights. I then removed the Upright and used a center punch and tried to be exact. I used the Drill Press to remove most of the material starting with a 3/32"/#40 drill bit, #30, #20, and 3/16". Then I clecoed the Upright back onto the Spar to make sure I could continue with a 1/4" bit, it was almost perfect and I drilled out to 1/4". This left a 1/32" shoulder and I used the drill guide with a 5/16" drill to finish the hole. This took a bit more time and WD-40 to get through the 1/8" Upright. It was worth the effort, the holes were perfect.
Spar bolts holes drilled, Center Spar ready to install, again.
This is out of sequence. I want to use the existing holes for the XL "T" doubler, so I need a template, hmm ...
So, I slipped the "T" behind the fuselage skin and marked the holes, I will actually drill. This is just a test.
To reinstall the Center Spar I used short bolts to position the Wing Attachment Upright and then clecoed to the Spar and then to the fuselage.
Same procedure for the front, but I used long bolts to go through the Center Spar.
I've started installing clecoes from underneath, it's a bit easier.
A view of the bend in the Front Upright.