Fitting the flap hinge - 2 hours

Fitting the hinge on the flap is fairly easy. After some time looking for the hinges that I tucked away 8 months ago, I finally found them and drug them out.
I used an edge marking tool to measure in 1/4" on each side as noted on the plans.

Next I clamped the hinge onto the flap assembly and checked that the line match up through the holes. After double checking that my hinge alignment was consistent with what is shown on the plans. I began to drill and cleco, re-checking alignment as I worked from the center to the ends.






Here is where my alignment ended up on the outboard rib.




and the other flap
 
 Well...Enough for the weekend. I am airplane'd out.
 

Debur and dimple the skins - 4 hours

A majority of the skin prep time was spend yesterday. Today I just needed to debur and to dimple. Takes some time, but in the end it is straight forward. The deburing when quick, then it was a matter of dimpling. Of course the smaller inboard skins can be done solo, but the longer outboard skins required an extra hand.

I temporary cleco'd them on the wing to get them out of the way.

I was sure not to dimple the spots that are to be drilled in the future for the wing root fairing.

But all in all, it looked great.

Devinyl and edge prep the skins - 7 hours

Well just when you had enough of dimpling and deburring when finishing the wing structure. Now you need to do the same for the wing skins. A very long a tedious process. But if there is some good music or some Netflix on the laptop. Time just passes by.

First I started by working the edges of the skins with a file to clear the shear marks off.

Next was the very boring and lengthy process to devinyl the skins



Now...I then dug out the 3M wheel on the die grinder and worked the edges smooth (doesn't take much, just a light once or twice over). Then I worked each corner with a file to round the edge. Thanks to my buddy mike he showed me a technique to help ensure a nice round edge. The technique is hard to describe (much better to see it). Essentially you push into the turn as you make it....so for example push the file left as you work the corner towards the right and back into you. Most folks drag the file with the direction that your turning. Increased the chance of an oblong fillet. Takes a little bit of technique but the fillets look great!
 
Once I was done, I then rubbed down each edge and corner with maroon scotchbrite. 
Next I pulled out the files and started the 'scarf joint'. Essentially you work the corner of each material (where they mate) so that the thickness between the two pieces are not stacked, but there is a transition. This goes fairly easily with a file. But be sure to make sure you keep the file flat to the piece.

Next was I pulled out my edge forming tool and worked the edge of each skin that meets the leading edge, and worked the edge of the outboard skin that overlaps the inboard skin. 

Here's a fun little tool

Went over to Mike's for a BBQ after work. When showing me some of the cool parts for the Stewart S-51 (works of art by the way!!) A cool little tool caught my eye.

What is it. Well...I picked it up and noticed right away that the 'hole' was about the same size as my mushroom head rivet set, but I couldn't figure out how or where it was used/placed.

Well with a big grin Mike showed my what it is used for.


It's used to keep the rivet gun in place when bucking solo.

What a cool little tool!!! Now I want one!!!!

And just a little more debur and countersink - 3.5 hours

Well this morning I found myself really questioning the dimpling of the inboard ribs. I had dimpled all the holes on the rib yesterday. The plans on drawing #12 to leave certain holes un-riveted for future attachment of the wing root fairing. Well of course I interpret this as dimple it all and not rivet some holes.

So after I did some checking on the forums this are seems to be a bit of a tricky area for some builders. First off the holes noted to be left open do not match between drawing #12 and #38. Next issue is do you not dimple these areas, or do you drill and dimple them now. Well...more reading on the forums and a message sent to Wirejock (Larry Larson) I think I have it figured out.

I've decided that drawing #38 is the correct drawing for locations. Everyone says "about every third hole". Ok...That's settled. Next Wirejock recommended leaving the hole undimpled and keep the #40 pilot hole. He said that I will use these holes to cleco on the fairing later.  Good enough for me!

So...Of course I had to flatten out the necessary dimpled holes on the left wing rib that I had done yesterday. Not a big deal as you typically can flatten a small dimple without structural issue. Better yet, down the road I will have to drill open these holes to a larger diameter anyway so its totally fine in the end no mater what.

Once I had the left wing fixed up. I needed to complete the few countersink holes and rib dimples that where left on the right wing. I then cleaned, masked off the front and rear spar and primed.

While I waited for the primer to dry, I prep'd the right leading edge skin (debur, edge roll, and dimpled) same as yesterday.

Little more debur, countersink, and dimpling - 4.5 hours

I had finished the majority of deburing and counterskinking however there is just a handful of places where I just couldn't reach the end (inside) ribs where my wing stand structure blocks access. I've built a slightly smaller wing stand structure than indicated on the plans to maximize space in the garage. It works, but I have to make some concessions to make it work. ie. I have to climb under the structure to access between the wings. I will have to rivet the skin on the wing, with one wing at a time. And of course in today's work session, I have to take the wing structure off the stand to access a few locations. Not the most efficient setup, but given that I need the space in the garage, this is a totally workable situation.

So I had pulled the left wing off the stand and finished the 6 or so holes that needed to be countersunk, as well as the handful of holes that needed to be dimpled.

Now it was time to countersink the rear spar (top) holes. The bottom ones are very easy to do with the pneumatic squeezer. The top side is another story due to the angle and interference with the rear spar. I've been giving this area some thought for a while, and I figured that my vice grip 3/32" dimpler would do the trick. I tested a couple of holes first and checked with a rivet. The dimple is not as nice as the pneumatic squeezer, but it works.



Once I was complete I pulled out my microstop countersink (having it set up for the main spar I just did) and I started to check the holes. Of course the holes that are dimpled with the vice-grips take some material off. I then checked the bottom of the rear spar that was done with the pneumatic squeezer and little to no material is removed. I decided that this is the correct setting and went to work cleaning up the top side holes on the rear spar.

Next order of business is to clean an prime the spar where the countersink holes are made. The manual indicates that this can be done as a spot prime while countersinking (i.e. when doing the tank screw countersinks) buy I opted to prime the whole face as some builders choose to do. I masked off the front spar and primed it. I had also primed the top of the rear spar where the machine countersink had removed the primer (and where the dimpling operation flakes off the paint).


As I let the primer dry...I moved on to starting to de-vinyl the wing walk doubler. Next operation was to debur. Now at the back of my mind, I had to keep my dimpling operation correct. I had chose to dimple the ribs for the wing walk doubler with tank dimple dies. The idea is that if I dimple the ribs/doubler skin with tank dies, and then dimple the skins with regular dies this will provide slightly better nesting. However....months ago when I dimpled the rear spar....I didn't use this thinking and I dimpled with regular dies. Confusing I know but basically when it comes to the doubler the bottom line for my build was this;

Dimple the rear spar line with regular dies, dimple the rest with tank dies. So...to make sure I mitigate the risk of messing this up at a later date. I dimpled the rear line.
 
Of course it wasn't midnight yet and I was still wide awake...why not do a little more I thought. So whats a little more deburing and dimpling? I took the left leading edge out and debured. Now...most important for me to remember. I used the edge forming tool and ran through to two edges. Next I dimpled.

More deburring and countersinking the wing - 3.5 hours

I decided to use 3/32" tank dies on the ribs and wing walk doubler (with regular dies for the skin). As such I double checked the countersink needed and came to the conclusion that it is the same depth of countersink that is needed for the thicker 0.035" skin. (As the wing walk doubler is 0.025" thick).

I ended up completing all the wing spar countersinks. Wow...what a lot of work. It's fun a first, but becomes very repetitive. I decided to re-tackle deburring for a bit before calling it a night.