Rear Spar (2h) – First Mistakes

Rear Spar (2h) – First Mistakes

OK. It’s been a few days since I last updated this blog and the reason why is because I was so pissed at myself that I did not want to come here.

I knew I would make a mistake sooner or later, so I guess it’s best it was sooner. The first and most important lesson that I learned is that this project is not a project to relax after a stressful day. I had a really awful week at work last week and I was trying to use this project to relax and this definitely did not help. But ok, let’s dig into the mistakes (yes, plural) I’ve made: 

  1. HS-411 – This was the first piece of the airplane that I had to rivet. The plans call to use a -5 rivet. I did place all the rivet and measured the shop head using a rivet gauge and the gauge tells me the size of the head is perfect. But it’s clear from the images that the length of the rivet is just not enough. Upon researching, I found this recent thread on the Van’s Air Force Forum: http://www.vansairforce.com/community/showthread.php?t=163172. Scott explains the difference between the AC43 specs and the MIL spec that Van’s engineering uses and basically says that they decided for a -5 rivet just because of the number of support calls they had with people messing parts with a -6. The RV9 even calls for a -6 in the same part. I will drill these rivets out and replace them for a -6. 

2. Still on the same part. When I was enlarging the holes in the base of the piece I was not careful enough and I did let the air drill touch the top of the HS411 part, nicking a piece out of it. This is something I would just not be able to sleep at night thinking about a crack fracture spreading and breaking the entire part. So I decided to just order a new one.

3. The next mistake is the one it really got me mad because man I did spend a long time reading over and over and over again the instructions before drilling and still I messed up. It was the HS-000003 spar doublers. These 2 pieces are part of a Service Bulletin from 2014 to prevent cracks. In my opinion, the instructions were just awful for this part. I did line up the existing holes in the spar with the holes in the spar doubler and when they lined up exactly I thought I had everything in place. These 2 parts do not have any indication saying one is to be used in the left and the other in the right so I assumed they were exactly the same. When I match drilled I quickly realized there was something wrong, looking at the other side I saw this: 

Yeah, This does not look right! So I basically ruined 3 parts. HS-814, HS-702 and HS-810.

New parts ordered and lessons learned. I’ll for sure be way more careful from now on. Just to try to avoid expensive mistakes too I decided to buy the DVD’s that George Orndorff recorded (http://www.fly-gbi.com/rv-678empmini.html). I do realize the kit has changed a little since he recorded the videos, pretty sure the HS000003 part is not there, but if the DVD can help me avoid 1 mistake it’s going to have paid for itself already. Buying new parts are not that expensive, but shipping and taxes are. 

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