Completed left flap - 3 hours

Now that I have some rhythm to bucking the flap rivets, I managed to crank out the bottom side of the left wing in no time. Everything went extremely well, again only had to drill out the odd rivet and re-try. 


But, just as I was nearing the finish line setting the last couple of rivets, wouldn't you know I let the gun slip and I've put a dent in the bottom of the flap skin. Ahh, stings. It's not structural, just cosmetic....but still not what I wanted. A little super-fill from aircraft spruce and primer and all will be just fine in the end.

I finished off the flap by using the squeezer on the end rib rivets and I was done.

Started assembly of the left flap - 3 hours

I started in on riveting the left flap. took some time to figure out best how to rivet and fall into a groove. But in the end my thin tungsten bar was the best. I quickly figured out that if I taped up the one end it would allow the bucking bar to sit high up off the work and would allow me to ensure that it was sitting parallel with the skin in such a small tight space.

I managed to set the top side, only had to drill out the odd rivet.


I used MK-319-BS rivets in those areas that you just cant buck. I use electrical tape to help prevent scratches when pulling the rivets. It works great.

Prep'd Flap skins for priming - 6 hours

Bit of a long day for the flaps. I had to debur the flap skins. Once that was done, I scuffed with scotchbrite. Next step after that was to dimple all the holes. Mindless work but sitting in front of Netflix while doing it passes time easily. I was sure to edge roll the flap skin where it mates with the bottom skin before dimpling.

 
Once all was ready, I took the pieces outside, wiped everything down with wax and grease remover, MEK and then primed. I decided not to acid etch these as it is quite a bunch of work and since the flaps are easily replaceable if needed I took a chance.
Later that evening after the primer had a few hours to dry on the skin, I mixed up some 3m 2216 structural epoxy to use as a liquid shim between the flap ribs/rear spar. I didn't need much of a shim at all (about 0.010") so the liquid shim will be just fine.

It works pretty good as it sets up incredibly well after about 8 hours ....however, one thing I didn't count on in its amazing ability to destroy a cleco.

Began assembling Aileron brackets - 2 hours

I gathered up the nerve to assemble the aileron brackets. I was dreading this step as I find driving the bigger, longer rivets at bit of a pain (more about the difficulty in drilling and removing rivets out of really thick material).

Well....I decided to jump in. Surprisingly everything when extremely well. First step was to set the AN426 flush rivets using the pneumatic squeezer.


Next I needed to set the AN470AD-11 rivets. Now this is where I was getting nervous. I find setting the AD470 rivets a bit more tough with squeezer as it is a tad tricky to ensure you are dead straight with the dies. (Dead straight results in great rivets....while if you are slightly off, it increases changes of a slightly slumped rivet head). It turns out that my squeezer just did not have enough power to set those AD4-11 rivets. So I pulled out my alligator squeezer. After some test pieces....Bam! Turns out it does an amazing job!



Since a few folks seem to have some questions on how the rivets are oriented on the hinge brackets, here is a few views of how I did mine.

Primed the aileron brackets, Prep'd flap parts for priming - 5 hours

I started the day off with acid etching all of the aileron bracket parts including the flap ribs. I set up and gave them all a coat of primer. I was careful not to get a thick coat on the aileron bracket parts, just a very thin coat. Have to make sure they fit together nice and still have holes line up.

Another big job was to start prepping the flap skins for priming. Lots of time taken in taking plastic off the flap skins and deburring. I managed to prep the right flap.

Re-drilled new flap ribs - 5 hours

I had rush shipped new flap ribs so that I could carry on with a big build this long weekend.So one of the big jobs was to re-assemble the flaps and begin the process of match drilling the parts. Learning from past experience. It takes a lot of care not to enlarge a hole that has already been match drilled. So it was a lengthy process, but in the end it worked out well.

I also deburred and dimpled all of the new rib holes (with the proper dies this time) and it turned out perfect.

Even more fitting and match drilling aileron brackets - 4 hours

One of the last items that I need to do is complete the rivets in the far outboard end of the wing (top skin). My compact wing stand did not allow me to reach these rivets in the stand, so I need to do them off the stand but before I begin to attach the aileron hinge bracket. So I made short work of the right wing.

 

Now that the right wing was ready, I started to match drill the aileron brackets to the wing. I really wanted to avoid getting aluminum shavings into the wings, so I used some scrap cardboard to direct shavings away.


 
 I also fitted the aileron stiffener S.B.
 

Another item on the to-do list was to address a bucking bar mark on the wing spar. A small mark was made accidentally when the bucking bar slipped while riveting, the mark was small and did not have an  edge, but the anodizing was scratched. So in the interests of maintaining corrosion protection, I removed the rivet, buffed the spot out with scotchbrite and primed it. Was it necessary....no, but I feel good that I did something with it.