For anyone mounting their wings on a RV-9a, this is what worked well for me:
(I wanted to write this up while it's still fresh on my mind)
Inserting the wings (the first time):
I pre-lubed the inside spars with Permatex aluminum style anti-seize so the wing spars slid in easier. Go easy on this stuff because a little bit goes a long way.
I built a table that was to the level of the bottom of the fuselage skin and then used a moving blanket and a fellow builder to teeter totter the wing up and down as it was inserted. The moving blanket was the fulcrum. This arrangement allowed this to be done with the help of only one person while I sat in the cockpit ready to pin the wing. That table also allowed me to work on the wing and even turn it upside down myself after wing removal for its nut plate fitting.
I used drift pins donated from a fellow builder which were turned down to a .003 smaller diameter. These slid easily into the 7/16" bolt holes if everything was aligned properly. Thank you Philip Groelz!
I inserted the top pin first because it was the most accessible. The bottom pin slid in easily when the dihedral on the wing was rather high as compared to the table below. I only pinned one top and one bottom with the .003 smaller pins. That is good enough for the first fitting.
Close tolerance bolts and final wing fitting: I used STP oil treatment on the shank only (keeping it off the threads). This helped a lot with the insertion. Have patience because these close tolerance bolts take time to tap and turn in. (I cheated a little bit here sometimes with an aviation hammer... )
Note: the bottom bolts have the washer on the head side and not on the normal nut side. This is because the side that does the turning is the one you protect with the washer. If you put two washers on those bolts, then you just may not get enough threads protruding from the nuts. Follow the plans carefully here.
Don't put in the 1/4" hardware until the AN365-720A nuts are installed in order to have more room down there.
Someone on a different thread said to use a crowsfoot for the bottom bolts. This was a great idea! The crowsfoot would drop into place and lock there as I torqued things into place. It took an extension bit and sometimes a very slight turn on the crowsfoot to get it to release but it did! I could turn the bottom bolt heads with both hands and not worry about the crowsfoot side with was holding the bottom AN365-720A nut nice and snug in there.
I used a 1" diam x 14" long pvc for a lever arm on the wrench handle for the final torque. (37.5-41.7) ft lbs or so and a little wrench handle is just too much force so the the lever arm made this final tightening easy.
I tried using various torque wrenches on the bottom bolts but what worked well was a torque adapter inline with the extension bits and sockets. I also had a nice 100W equivalent LED light shinning on the area for good lighting without generating too much extra heat. I used a small inspection mirror to help align the holes during the wing insertion and pinning process.
I used a combination of multiple extensions and sockets for the AN7 bolts: 6" & 3" extensions, 11/16" sockets of various lengths and a 5/8" crowsfoot. In my case, I had an overall socket, extension and/or torque adapter hardware length stackup of around 8" from bolt head to the wrench. This cleared the aileron push tube well.
Good luck to anyone doing this. It takes some time so you must have patience.
(I wanted to write this up while it's still fresh on my mind)
Inserting the wings (the first time):
I pre-lubed the inside spars with Permatex aluminum style anti-seize so the wing spars slid in easier. Go easy on this stuff because a little bit goes a long way.
I built a table that was to the level of the bottom of the fuselage skin and then used a moving blanket and a fellow builder to teeter totter the wing up and down as it was inserted. The moving blanket was the fulcrum. This arrangement allowed this to be done with the help of only one person while I sat in the cockpit ready to pin the wing. That table also allowed me to work on the wing and even turn it upside down myself after wing removal for its nut plate fitting.
I used drift pins donated from a fellow builder which were turned down to a .003 smaller diameter. These slid easily into the 7/16" bolt holes if everything was aligned properly. Thank you Philip Groelz!
I inserted the top pin first because it was the most accessible. The bottom pin slid in easily when the dihedral on the wing was rather high as compared to the table below. I only pinned one top and one bottom with the .003 smaller pins. That is good enough for the first fitting.
Close tolerance bolts and final wing fitting: I used STP oil treatment on the shank only (keeping it off the threads). This helped a lot with the insertion. Have patience because these close tolerance bolts take time to tap and turn in. (I cheated a little bit here sometimes with an aviation hammer... )
Note: the bottom bolts have the washer on the head side and not on the normal nut side. This is because the side that does the turning is the one you protect with the washer. If you put two washers on those bolts, then you just may not get enough threads protruding from the nuts. Follow the plans carefully here.
Don't put in the 1/4" hardware until the AN365-720A nuts are installed in order to have more room down there.
Someone on a different thread said to use a crowsfoot for the bottom bolts. This was a great idea! The crowsfoot would drop into place and lock there as I torqued things into place. It took an extension bit and sometimes a very slight turn on the crowsfoot to get it to release but it did! I could turn the bottom bolt heads with both hands and not worry about the crowsfoot side with was holding the bottom AN365-720A nut nice and snug in there.
I used a 1" diam x 14" long pvc for a lever arm on the wrench handle for the final torque. (37.5-41.7) ft lbs or so and a little wrench handle is just too much force so the the lever arm made this final tightening easy.
I tried using various torque wrenches on the bottom bolts but what worked well was a torque adapter inline with the extension bits and sockets. I also had a nice 100W equivalent LED light shinning on the area for good lighting without generating too much extra heat. I used a small inspection mirror to help align the holes during the wing insertion and pinning process.
I used a combination of multiple extensions and sockets for the AN7 bolts: 6" & 3" extensions, 11/16" sockets of various lengths and a 5/8" crowsfoot. In my case, I had an overall socket, extension and/or torque adapter hardware length stackup of around 8" from bolt head to the wrench. This cleared the aileron push tube well.
Good luck to anyone doing this. It takes some time so you must have patience.
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