Hinge Nightmare

After the primer had dried over night I started the shop day by putting together the upper hinge assembly to finish the V-Stab.
Clecoed everything together and then rivetted the thing with AD4 rivets. After doing the three closest to the bearing I tried it to see if the bearing was still moving freely.... and: Damn! It got stiff again and would hardly move at all. The same problem I had before.
Thanks to the Van's Airforce website I had found out that the only reason why the bearing could lock up is pressure from the cage surrounding it. I checked the assembly again after drilling out the three rivets and I found a hint of primer on the inside of the assembly right where the bearing is sitting on. I could hardly believe that this little could have such a huge effect but I was getting desperate and in lieu of another clue I went on and scrapped off the little paint spray dust that got on it. Once it was all shiny on the milled surfaces again I put it back together started rivetting and .... you wouldn't believe, it worked!. I set all 5 rivets and the bearing was moving freely just like before when the hinge had been clecoed.
So, be careful with the milled surfaces and make sure they are totally plane and clean before wasting your time on it!
The image shows the finished upper hinge assembly next to the primed parts of the previous attempt (notice the thick layer of primer in the bearing cut outs) and also visible are the unmodified parts of the hinge as Van's sent me an extra set of parts.

Screwing on the hinge onto the V-Stab was a piece of cake after that. You'll see pictures of the whole assembly when I trial fitted the rudder spar to the V-Stab.

Preparing the Rudder Ribs

So Van's had sent me the replacement parts to rebuild the upper hinge assembly for the V-Stab and so it was prep time again. As I wanted to prime the parts I took care of some more parts as the rudder ribs got drilled anddeburred and were ready for priming as well. As my Cortec primer finally arrived I wanted to use this expensive stuff and see if it really works wonders or not. This type of primer (Cortec VcPI-373 and the surface preparation with Cortec VcPI-440) is supposed to be applied with a spray gun and I had to learn how to use this tool before I felt good enough to try it on the real parts. I'm still learning the little details but for primer work I'm doing good enough.
I have to say that I'm pretty impressed by the Cortec stuff. Environmentally not too harmful, no nasty fumes and still a great result on aluminum.

V-Stab finished... almost

And so I finished riveting the skin to the V-Stab the other day. Nothing surprising happened (I consider this a good thing). The only noticeable thing that happened was that my shop A/C broke and with over a 100 degrees it's a bit too hot out there to work without it. A replacement unit is on the way (the first just got 3 days old before it broke).
Fitting the nose of the V-Stab looked like a real bad job but when I screwed it on it just pulled itself in place. NICE!
So that was it with the V-Stab - except for screwing on the upper hinge assembly which I can't do as the parts are still on their way from Aurora. The previous parts couldn't get riveted without causing the bearing to freeze up,
On of the first assembly steps for the rudder is to trial fit the hinges with the rudder fittings and I don't want to get too far ahead this time. There might be a reason why Van's wants you to do it before assembly.
So, I'm limited to deburring and finding a place where to store all those parts I will eventually have assembled ...
Overall time for the V-Stab was around 35 hours.

Stabilizer skinned

In the morning, before going to work, I finished squeezing the last 9 rivets for the nut plates. I just couldn't let it sit like this.
In the evening I put the skin on and the fit appeared to be good. So I continued clecoing the skin on, beginning from the leading edge on one side. Everything looked good but I wanted to be sure and so I turned the Stab and tried to cleco the other side as well (raising the Stab on some coffee cans to clear the clecos from the workbench). After I did that I was pretty amazed that it looked like I was already ready to rivet the skin on - but then I noticed little buckles near the leading edge in the front areas of the ribs. It wasn't the radii that had been excessively trimmed in the previous steps, it appeared to the be the ribs being too long and the upper front pinched into the skin. So I took the skin off (oh my, why did I have to send my air cleco tool in for repair TODAY?) and the scratch marks on the inside verified that it was the rib webs being a bit too long. The die grinder took care of that and I made sure I wouldn't have to do this cleco party again! Scotch-Brite polishing, re-priming the rib noses, priming the inside of the skin, particularly where it got scratched and along the rivet lines didn't take long.
Then re-skinned, aligned and adjusted and finally riveting started. I got as far as finishing one side and starting the leading edge on the opposite side. The process is a bit slow as you have to go one by one in the leading edge area because of the high tension there.
Anyway, the V-Stab is almost finished!

VS skeleton ready, skins prepared

Tonight I finished the assembly of the VS skeleton, and put it aside to make room for the VS skins. Final drilled the #19 holes in the front and main skin and dimpled the nut holes and the rivet holes for the nut plates. I'm not sure how straight the edge of the front skin has to be that has to be trimmed after removing some excess material. I was very careful when removing the material but the edge doesn't seem to be completely straight. We'll have to see how that will look when the two skins will be put together.
When riveting the AN426AD3 rivets for the nut plates my hands grew tired on the last batch of 9 rivets and I had to give up for the night as I didn't feel I could still do a good job squeezing them. Those rivets are small but a large number of them gets me tired after a while. I think I'll be dreaming of a pneumatic rivet squeezer tonight. If only they'd be more affordable...
Just summed up my worked hours on the VS ... about 26 so far.

2 steps forward, 1 step back

It was a busy weekend and I had a lot of fun, until I discovered that I got carried away and riveted way too many holes that weren't supposed to get riveted just yet. Well, at least I had a lot of practice with my rivet removal tool - oh, how much fun I had!
But there is hope! It seems I am learning from my mistakes as I didn't repeat the same mistakes on the left side of the rear spar, so the caps went in well and also the countersinking seemed much better this time.
I am still having trouble with the upper hinge assembly, as the bearing seizes when I rivet the brackets. The lower hinge worked just fine, but the upper one I riveted 3 times before giving up. I sent an email to Van's Tech Support.
The primer rattle cans arrived and I started priming the first parts of the vertical stabilizer that were in the queue for assembly, I also started riveting my first pop rivets. That Avery gun worked great and I had so much fun that I just riveted along. Unfortunately, I riveted much more holes as I should have, but I am repeating my self. After removing the unwanted rivets it looked like I got hardly anything done besides burning time...
Fortunately I spent Saturday at Aero Fair in Payson, AZ (KPAN). The flight was a lot of fun and passing Apache river and Roosevelt Lake was very impressive. To clear the mountains in thermal conditions I flew up to 9500 ft. I've never been that high in my little butterfly LSA :-)

A good day at the factory

Yesterday evening I had a real good time at the aircraft factory! At least, that's what I'm thinking now as I haven't found other issues yet I might have created.
I copied the assembly preparation for the left upper and lower spar cap from the already finished right side. This time, though, without making the same mistakes again!
I've also learned how to avoid having different results with the countersinking cage for every hole dealt with. My friend Tom who built an RV-6A told me to go real slow in RPMs when using the cage. So I put the cage on my electric screwdriver and - voila - no vibrations that elongate a hole and a nice and repeatable(!) depth. I tried to use the drill press, too, but it created the same problems as my pneumatic Sioux drill did and I even tried to slow the drill press down to around 500 RPM. Either way, I got different depths and sometimes elongated holes. The screwdriver is the way to go for me.
So far I've spent about 14 hours working on metal.
Sorry, no photos yet, I was too tired last night when leaving the factory.
Oh, because my Cortec primer (VpCI-373) is not going to be here soon, I ordered some rattle cans of Tempo Zinc Phosphate to get started with the riveting. It will also help with priming small amounts of parts that wouldn't justify the setup and cleaning of the paint gun.

right VS spar assembly ready

I finished the right side of the VS spar today and promptly ran into my first problem. Among all the match drilling were 6 holes that were much bigger than the others (#12). I was so in my drilling flow from all the #40s and #30s that didn't pay too much attention when drilling the biggies. It seems that I didn't center the drill bit when I drilled and I created elongated holes in the spar for half of them. The match drilled parts underneath had perfectly round holes in them so I know it must have been a centering fault.
Fortunately, it seems I could fix that by widening the holes a bit with a Dremel tool without removing too much material.
This taught me a good lesson though - never just drill without double checking that you really want to have a hole right there.
This section required a lot of material trimming and I'm not sure if I'm using the right technique (filing) but the result sure looks great, so I'm not too worried about it. It's going to be about 3 weeks until I get my primer, so I shouldn't go too fast right now.