Ron's RV7 Aircraft Factory


Welcome to my personal blog. This site was created as an informal description of my build progress in the construction of a Van's RV7 aircraft. A place where family/friends/builders/curiosity seekers can follow along. It is not intended to be a detailed description of every step in the building process as that would be much too time consuming. There are plenty of sites that do a great job in that arena, that is not my intention with this site. My intention is for this to be a philisophical/motivational/inspirational account of the emotional ups and downs of the life changing journey...and it will change your life. I hope this will give you an idea, through my eyes, of what its like to make this transformation. A note to other builders, I am not an expert so do not put your safety at risk by attempting anything you see on this site until you have done your own research, or send me an email so we can discuss it. Any deviations from the plans are not approved, nor endorsed by Van's Aircraft or myself. Thanks for visiting.



Saturday, May 2, 2009

Ouch...first mistake! HOBBS: 17.5 hrs

These are the angle alum that splices together the rear Horizontal spar. These had to be bent to a 6 degree angle...more on that later.


Starting to cleco the horizontal stab parts together, this is exciting to see it start to look like part of an aircraft!
Adding the skins for the first time....

This rib needs to be match drilled through the rear spar and the nose rib. The plans were a little unclear on exactly how to do this. My strategy was to assemble the skins so I now exactly where to locate the mounting holes for the rib. I wanted the rib edge to flush with the skin. You can see where I marked a red line with my Sharpie.


Aaaw, look at that...its a horizontal stabilizer!!! This was fun, assembling everything to see what it looked like.

This is how I came up with my 6 deg angle mentioned earlier. Hmm, how to measure out a 6 deg angle?? My plotter from pilot training, that should look familiar to all the pilots out there. Just happend to have it laying around. Worked good, probably not too precise but close enough for this task.


Cutting the nose rib to fit....the red lines show the task at hand.

Used a cutoff wheel in my dremel tool, worked great, they came out nice except for one thing. Although the plans dont call out an inside radius, it does show one. I should've added a radius. Sharp inside corners like this are great for stress concentrations.

Not wanting to have these ribs start to crack, I added some relief holes in the corners. They came out nice and should eliminate the stress concentrations I was worried about.

I had heard of other builder getting these holes too close to the edge. I thought I would be clever and mark my holes on this nose rib instead of the main rib, that way I know I have my minimum 2d (2x rivet diameter or 0.25" in this case) edge clearance. Seems all well and good, the intentions were definitely well founded. But here is where my trouble started....
So here is an illustration of why those notches were needed. They fit around the splice angle aluminum. Although I have it upside down in this pic, you get the idea.
So I mark my holes accordingly to match the nose rib. Now I have to drill through the rear spar and into the main rib so all three parts line up. Once again, seems like I am on the right path here.


But here's my SNAFU...since I wasnt exactly sure where this hole would come out, nor did I think about it to be honest, I was kind of stuck since I had already drilled the nose rib. In this pic you can see the drill hole in the middle. I am clearly too close to the edge!! It should be 0.25" and it is about 0.15"...only 1/10 of an inch, doesnt take much. Damnit...and a few other choice words! :) I didnt think it through from start to finish before commiting to drill holes. So, that was it for the evening but I tossed and turned all night trying to think of a way around this mistake without ordering new parts. When morning came, I knew the right course of action was order new parts, and redo it the right way. No cutting corners, I dont want to be in 4G pull, wondering about that rivet that I should've replaced and whether my tail is about to come off! My first mistake, and it came fairly early. Since it affected four parts (2 nose ribs, main rib and the rear spar), it was a $50 hit to order new ones from Van's, on top of the lost time. Lessons learned: #1, think it through from start to finish before committing to drill holes...I was well aware of the first steps but forgot about the last step. #2, if you have to do two symmetrical sides...do them one at a time so any mistakes you make dont propogate to both sides, it would've saved me one nose rib in this case if I hadn't drilled both of them at the same time.

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