Week 7: Right Wing Frame

This week I continued working on the right wing. About half the time was spend countersinking the main spar. I think I have them at a good depth, but I will find out for sure when I start attaching the first skin. If anything they will need to be a little deeper, but I wanted to be sure not to go too deep as that could comprise the strength of the joint. It is also always easier to remove more material than add some back in...

When that was done I was able to start attaching the previously assembled wing ribs. I first did a test fit, and found that I would have to be careful about when the flap torque tube was installed. I had to remove the next couple of ribs to have enough room and then was able to get it inserted into the bushing on each end. The bushings were a tight fit, so I used a teflon lubricant spray to make it a little easier.

After I had everything test fit, I decided to remove ribs 1-4 to make riveting to the main spar easier. The rivets install from the rib side but do not extend through the full thickness of the spar. This meant removing the flap torque tube and reinstalling it after the ribs were in place. With those done I was able to permanently attach the rest of the ribs as well.

Once all the ribs were riveted to the main spar, I attached the rear spar to the trailing end of the ribs. I had planned on adding the skin support to the rear spar at this point, but when test fitting it I noticed it would prevent an angle from being installed at the outboard end of the spar. This angle has to go on after the wing is removed from the twist jig, so I will wait until then to add the skin support.

With the wing frame fully assembled I began attaching it to the twist jig. I have the outboard end attached, but ran into an issue getting the AN7 bolts through the holes in the wing spar on the inboard end. I need to get a 7/16" drill bit to open those holes up to the correct size. When that is done I will re-check that both of my work tables are perfectly in-line and level so that the twist jig can set the wing in the correct position.