Well, it was bound to happen, but here we are. I am re-ordering my first part from Van’s. I get it – everyone does it, but that doesn’t make it any easier. I will admit that it is a real confidence shaker. I find myself going back over other work and looking for defects now too. Happily I’m not finding any, but a significant mistake will do that to you. Ugh… this is frustrating. Here is the big problem:
You need to fabricate these little guys completely from scratch out of angle aluminum provided by Van’s. I did a really good job on the dimensions, the drilling, and the round overs. Overall I was extremely proud of them until one tiny little knick on the front one on the left with my bandsaw. I made a shallow gouge (measured at 1/64th inch) on the surface of the part. That is more than enough to encourage cracking and breakage along that line over time and these two brackets are the mounting brackets for the entire horizontal stabilizer. Kind of a big deal. Suffice to say I’m not pleased with this effort and will not be using these parts on my plane. I have ordered more aluminum from Van’s today and hope to have it shortly.
I tried to zoom in so you can see the gouge. I know it is slight, but again, this is all it takes to encourage cracking along this line. Airplanes endure a lot of vibration, fatigue, and numerous stresses during flight. Lines such as this are starting points for that fatigue to manifest into catastrophic failure. This plane has to serve me for decades! I won’t accept anything except a plane in perfect condition. Time to refabricate this part until it is perfect.
The rest of the day was spent getting ready to build out the other spar on the horizontal stabilizer. Similar to the rudder, it involves using the bandsaw and cutting some spar caps to size and tapering them at the ends. It wasn’t too bad – just tedious work. Then came clamping them down, match drilling the holes, deburring everything, then clecoing them back down and match drilling the flanges on the sides. I realized that I was starting to make some silly mistakes like skipping holes or missing some spots to deburr so it was time to go inside. I have long recognized the diminishing return on labor when you are distracted or tired. Nothing good would have come from attempting to push through it.
Total time today = 4 hours
Total time empennage = 46.5 hours
Total time aircraft = 46.5 hours