Finished the right flap - 6 hours

I dove into the right flap feeling confident that I had the knack, and boy was I flying. Again, had the odd rivet to drill out..maybe 2 in all if my memory serves me. It was very easy to reach all the rivets with that thin tungsten bucking bar. Again, the fact that the one end is taped up really saved the day and helped greatly with setting the rivets straight.



Unfortunately I really had some difficulties squeezing the rivets in the end rib. They just wanted to fold over (even when the length was correct). I was using the no-hole yoke and I have to say from past experience, it can be temperamental. Some days it sets just fine, other days not so much. Today it wasn't working well. I had to drill out and re-set a bunch of them, only one hole (top side at the very bottom) I had to drill out a couple times, and ultimately I decided to use an MK-319-BS rivet, which is a tad annoying cause on the left flap I actually was able to set a solid rivet there. 

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.