Problem Solving

Mark had an enjoyable and productive week.  We've discovered that although we would really love to spend more time on the plane during the week, we simply have to devote some of our attention to our jobs and the other committments we have.  We've also discovered how gratifying it is simply to solve minor problems that creep up in the course of building.

On Monday (3/8/10) Mark spent about an hour working.  In that time he was able to screw the forward skin on the VS.  It really is incredible how well it fits!

He then clecoed the hinge brackets onto the rudder spar before a trial fitting against the VS. By doing this he could determine what washers would be needed for a good fit.  Amazingly the rudder was able to move with seemingly no friction using the first washers he choose.  Mark was really pleased and admitted that the way these pieces so easily came together gave him a sense of confidence for the rest of the project.  "It is going to be nice to fly a plane where I know exactly how each fastener was put in and how solidly it is built!"

Mark had to devote his Tuesday evening to his graduate school work and therefore was disappointed that he couldn't work on the plane.  However he and his dad were back at it on Wednesday 3/10/10.

The plan was to begin with squeezing the rivets that attach the main rudder rib to the spar through the spar caps.  The very first squeeze caused the rib to pull away from the spar so they had to drill it out. When Mark tried to describe what dilling out a rivet without messing anything up is like he said "it is like drilling a cavity. Instead of hitting the root with the drill, you end up enlarging the hole which is just as painful!" 

On the second attempt they decided it would be better to put the rivet through the spar side with the manufactured head on the spar side.  When they tried this arrangement the rivet bent! Thinking that the rivet bent because the rivet squeezer had been at an angle, they tried again.  The second rivet also bent.  As soon as this happened it was time for a little problem solving; if a rivet bends when you squeeze it, there is a good chance that it is too long. After checking the length of an unsqueezed rivet and confirming their suspicions their next challenge was to drill out the rivets.  Yep. . .you guessed it, Mark "hit the root" and enlarged one of the holes. That rib goes into the scrap heap!The rest of the evening was spent fabricating a rivet squeezer holder that will hold the entire squeezer solidly while squeezing the big rivets.

Thursday night Mark spent most of his time trying to figure out the best way to grind down the rivets slightly.  He finally discovered that he could put one of the too long rivets into a piece of scrap aluminum bar, clamp it down, and grind off a bit of the length. This method resulted in a perfect fit when it was placed in the spar for a length check. After grinding down the remaining rivets he decided to squeeze away and managed to expertly fasten the main rudder rib to the spar.  While it wasn't the most work Mark had completed in an evening, the simple fact that he solved the a problem made the evening productive.

The new rudder rib was sitting on the porch when we got home from work on Friday.  Mark hustled to the garage to debur the new rib (actually it was two of them. . .just in case).  While I worked on dinner Mark was able to get both ribs primed and ready for attachment to the spar.  It took me a while to get dinner together so he had time to attach one of the rudder hinge brackets with the fancy rivet squeezer + support.  They are some of the best looking rivets if I do say so myself. 

 Dad came over to help, which is a good thing because Mark needed an extra set of hands to hold the long rudder spar when squeezing the rivets. Between the two of them they made short work of the rest of the rudder skeleton; only needing to drill out one rivet. (They didn't have any problem with this one as they were able to use the drill press.)  They finished the evening by installing the remaining ribs using pulled rivets, a welcome change after all of the squeezed ones. Ahhh compressed air doing the work. 

Today, the first day of Spring Break, was devoted to prepping the rudder skin and then closing it all up.  The skin was filed, and clecoed onto the skeleton to ensure a proper fit, and then unclecoed.  Mark and Dad developed a good system, with Mark taking care of unclecoing and cleaning the holes, and Dad pulling the rivets.  We're now at a good stopping point, as we're headed out of town for a few days of R&R.