314 hours on the hobbs, Finish the Rudder and Let the elevators rise!!!!!

....Some final thoughts on the rudder. Just a couple more pics to show the details of the temporary hinge pin that I had to forcefully remove in order to separate the VS and rudder as described in my previous post. See the etched marks where the 1/2 inch cold chisel was placed to try to hammer out the pin from the hinge. Nice thing to have to do to something attached your aluminum airplane, huh!

The marks on the curved part are where the cold chisel was place. The marks on the top part were made by the hinge as I tried to pound this little sucker out.

Next is the tip of the temporary hinge that I had to cut off with the dremel tool. Not a real good pic, but if you look closely, you can see the ridge that had built up on the end, right next to the hinge plate, which is why I could not remove it easily. Thanks a gain Van's for not elaborating on the need to drill out the hinges to final size. (Still pissed off about that!)

And lastly, a set of new temporary hinges from Aircraft Spruce (Actually made by Avery tools). I ordered these fr several reasons: They have the threaded end on one end along with a threaded holder for ease of placement/removal, and they are short enough to allow for full control surface travel one placed in the hinge. They don't have that stupid long extension that gets in the way. The threaded holder allows me to get leverage on the hinge via the screw threads instead of having to pound it out with a hammer. Of course, now that I know I need to finish drill all the hinge holes to the correct size, I don't expect to ever have a problem with this again.

Now on to brighter things - -no more rudder for a while -  on to the elevators, which make the plane go up and down......

The process is very much like building the rudder. Starts with stiffeners as the main support element for the elevator skins. Here is my little work table setup that I clamped to the work bench. I decided to trim the stiffeners outside this time to keep from messing up my inside workroom work benches. Thankfully the elevators are a bit smallers in all dimensions from the rudder, so all the structural pieces are a bit smaller as well. I clamped a small piece of partical board to the the end of the workbench to allow several edges to place the angle for the stiffeners depending the cut I needed to make, and used my dremel tool with a extension shaft that I got for christmas to provide a bit more control while trimming the stiffeners.

I use two different types of REINFORCED cutoff wheels. If you use a dremel tool, and I can't for the life of understand how you will be able to finish a kit like this without one, do NOT use the small flimsy non-reinforced wheels that typically will come with a standard dremel tool kit. Use the larger, reinforced ones, adn remember to where ear adn eye protection when you trim the stiffeners from the angle. Why use  dremel instead of the shears as Van;s suggests? Because the shears leave serrated edge on the metal and are not well suited fortrimming smaller parts. The edge has to be filed down to remove any stress risers, whereas the dremel cut is much easier to cleanup with the Scotch Brite wheel.

And a shot of pretty much all the equipment to get the job done. Be sure to buy the economy pack up cutoff wheels - you will run through many of them:

A shot of the rough cut stiffeners after using the dremel tool to trim them to initial shape. Edges are very sharp and jagged at this point, so be very careful handling these pieces..

Note that I always leave some excess from the cutline on purpose so that I can bring then down to final shape using the scotch brite wheel, which is much easier to control. I also take the time to get the tail end each stiffener small enough so that when the elevator is bent the edges of the stiffeners will not interfere with the skin.

Thes next three pics are of yet another screw up that may actually cost me a new right elevator skin. I had cleanup the stiffeners and dimpled them, and was then in the process of dimpling the right elevator skin. I thought I had developed a sure fire method to prevent pounding a dimple hole in an unwanted place on the skin, but I managed to find a way around it.... THe pics that follow are what is know to us builders as the dreaded figure 8 dimple, because that is what it looks like when you screw it up. The new hole is close to the actual hole and this creates the figure 8 effect. IN my case, I tried to smooth out the bad one with my flush set, which worked pretty well, but then I tried to dimple the original hole and ended up with a crack that I now have to resolve somehow. I have posted the pics to VAF to get some opinions as to the best method to try to finx this. Hopefully I won't need a new skin. The first two are on the underside of the skin, and the last pic is looking at it from the outside. Can't let this crack go unattended or it will surely continue to crack later on...

As a well known participant on Van's Air Force forums always says, "It's just one damn thing after another...."

Oh, and to finish up - went on the annual dove hunt with my youngest son and my neighbor, a fellow CFII and coworker. We caught a couple of pics of some awesome sunrises out there that I thought I would share. This is out in Northeastern Colorado in farm and cow country. I can't wait to see some more of these types of scenic views from the air. Hope you enjoy them.

308 hours on the hobbs - Back to the Rudder (UGGGHHHHH!)

Had a bit of a scare the other day that I might have ruined both my VS and Rudder. Before I get into that, let's pick up where we left off before Oshkosh. I was almost done with the leading edges of the rudder. Lessons learned were:

The bend that was made with the bar  as described in my previous posts is only an INITIAL bend. You still have to do more bending (most end up doing this by hand) to get the holes in the edges to line up with each other so they can be pop riveted into place.

The plans clearly show that you MUST bend the leading edge skin near the edge of the spar flange in order to close them up so that the nicely curved edge is the proper distance away from the spar web. Very confusing since they spend so much time telling you how to bend the skin so that you DON'T end up doing exactly that.

Anyway, I used a techique of pushing down on the outside and up on the inside of the skin on the top to try to keep from creasing the skin next to the spar flange. Creases in the skin right next to the spar flange cause stress risers when flight loads are imposed on the control surface, which can cause crackes to form. I know this sounds confusing to you other builders out there. Just think of it this way. The initial bends were made with the skin down or on the surface of the board with the J bolts. The final bends are done in the opposite manner, pushing down on the skin on the top side to close the gap.

Here is a pic of all three sections closed up and pop riveted.

That pic does not show the crappy way that the middle and bottom skins turned out. To put it simply, the initial bend method that used (with the J bolts holding the bar and skin down flat on the table, worked SO well that I actually over bent the edges of the skins. They were initially bent so that the edges were almost at a 90 degree angle to the spar web. which the way that they should END UP when you are FINISHED bending everything. UNfortunately, as I stated previously, I still needed to finish bending the skins to close up the gap that still existed after the initial bends on both sides were completed. this ment that the edges of both skins ended up being well OVER 90 degrees to the spar web, causing them to curl up adn back toward the spar web just enough to caause me some severe headaches. This next pic shows the outcome. Notice the stressed edges of the inside skin in between all the pop rivets. This is the inside skin still wanting to curl back toward the spar web, but I am effectivey forcing the inner skin to attach to the outer skin. The result is that the edges of the skin are not flush with each other throughout the entire length of the edge:

I had problems getting some of the pop rivets to grab the inner skin so that it could be pulled tight against the outer skin. This was because in some areas the inner skin was curled inward  a bit more than the rest of the edge. So I was left with a decision, Replace the entire rudder skin since I had streched it too far, as one tech counselor told me, or devise a way to get the inner skin close enough to the outer skin so that the pop rivet would grab it. I chose the latter. I've spent way too much time on this damn thing already to even think about replacing the otherwise nicely attached rudder skin. I came up with a sort of lever that used 1/4 inch thick by 1 inch wide steel bar from HD, and a couple of small wood dowel sections, one taped to the end of one side of the bar, adn the other taped to the opposite side of the bar in a location where it could be used as a lever to push the inner skin outward after inserting it inside the curved section. Again, confusing as hell, I know. I forgot to get a pic of the lever so I will do that post again tomorrow. It actually worked fairly well, but required three people to get it to work correctly - one on the lever, one on the pop rivet gun, and one holding the rudder down so it would not move. Quite the operation but it did the job.

The LE skins are now all pop riveted into place. The only problem is that the middle and lower sections of the rudder LE are a bit concave when you look at them. This is due to the outer skin being pushed into the inner skin, and being drawn closer to the Spar web due to the over bent inner skin. Not happy with the outcome, but I have learned my lesson, so the elevators adn airlerons should come out looking very pretty.

Now on the next problem. After getting the LE skins closed up, I wanted to see that baby all hinged up on the VS. So I pulled down the VS from the garage shelf that I built, pulled out the 3/16" aluminum temporary hinge pins that I purchased, installed the rod end bearings in the rudder per the plans, and proceeded to insert the rod ends into the hinges. I found that the hinge holes were not quite large enough to fit the pins, After some research, I arrived at the conclusion that a 3/16 inch reamer would clear out each hinge hole enough to insert each hinge pin., and this seemed to work OK, but I noticed that each pin did have a little bit of resistance when going through the hinge holes. Then I swung it back and forth, with the RV grin all over the place, with the knowledge that had just completed my first full assembly of a stabilizer part and its corresponding control surface.

Then came time to remove the pins so that could move on to the elevators. Well, the bottom and middle pins all came out fine. but the top hinge pin would not budge. Short story is that a ridge had built up on the hinge pin due to inadequately reaming out the hinge holes, and this prevented it from coming back out of the holes. I ended up taking a small cold chisel that would fit in the confied space where the hinge is installed, and avery hard hammer, and banging the living hell out of it until it finally came out far enough for me to bend te hell out of the steel hinge half so that the bearing of the rudder would finally be free so that I could get he rudder off. Then I had to take my dremel cutoff wheel and leterally had to cut the tip of the hinge pin off in order to get it off of the hinge. I'll just close by saying that this ruined a perfectly good evening, and I almost ruined both parts in the process.

Further inspectiosn revealed that the hinges were still in good shape, and the rod end bearings on the rudder appear to be OK as well. SO I think I averted disaster yet one more time. The moral is that 3/16 " is a bit too SMALL for the 10/32 bolts that will eventually fit in them, as well as the 3/16" hinge pins that used. What I really needed was a number 12 reamer, which I did not have (have one on order as I write this). I did, however, have a number 12 drill bit. SO I used that to further ream out the holes. Just trust me when I say that the amount of material that was being removed by both the 3/16" reamer and the #12 drill bit, were basically dust particles, but apparently this was enought to make the difference in the pins fitting correctly or fitting too tightly in the hole.

Pics will help clarify this mumbo jumbo I hope:

Look towards the top of the pic on this one to see the sligt divet or inward bend of the skin. This is that concave result I spoke about earlier:

While I really wanted to try to put solid rivets in everything on the rudder, the trailing edge finally beat me into submission. You are given the option here to use pop rivets since the clearance in this area is so small. I was in the process of making a small bucking bar out of the 1/4 inch thick steel bar I mentioned earlier, but I finally caved in and said WTF and took the easy way out by using the pop rivets. Nice hole, eh?

Here is the original "happy moment" when I thought everything was coming to gether nicely. The hinge pins are in place and the two assemblies are now joined into one.

Next is a pic of the bottom temporary hinge pin in place.the temporary pins are used so that you do not put unnecesary wear and tear on either the hinge hole or the threads on the actual bolts that are used. the pins are smooth and are soft aluminum so they are not supposed to cause any damage or difficulty. (HA!)

And another seemingly happy moment, all before I realized I could not remove the rudder due to the stuck hinge pin:

And one last shot of the hinge pin assembly before I call it a night. Tonight I reattached the lead counterweight to the top of the rudder, hopefully for good this time. Torqued it to 30 inch pounds. Just a little powder coat touch up on the hinge brackets, and the VS and rudder can go to sleep for a while while crank out the elevators. 'Gnight all!

Oshkosh Airventure 2011 Interrupts the build!

At about 302 hours I had rolled the leading edge rudder skins and did my best to finish closing the skins and pop riveting them together. It became clear that my initial rudder bend had actually worked so well that I ended up over-bending the skins. This created some problems when I tried to insert pop rivets in the last couple of holes in the bottom section. The inside skin would cleco OK to the outerskin, since the shaft of the cleco is long enough to reach inside, but as soon as I let loose of the cleco to try to insert the pop rivets. the inside skin would tuck away from the outer skin to the point that the pop rivet would not be long enough to grab hold of the hole in the inner skin, no matter how hard I tried to push in on the outer skin to close up the gap.

At this point I had about 1.5 weeks remaining till Oshkosh, and it felt like I was in hell week trying out for the Navy Seals just so I could finally get head up to Airventure 2011. The trailer was in the shop for some needed brake repairs which I had to force them to make twice before the problem was finally resolved. I learned after I got back that the tech that supposedly worked on them the first time was fired after failing to properly fix my problem. Apparently he had done the same thing to two other customers before me, so the shop manager cut him loose. I have read some stories about aircraft mechanics doing essentially the same thing while working on some airplanes. Just one more reason why I only trust myself to work on MY airplane when the time comes.

Work was also making me insane, since I was finishing up a project that I had worked on for the last 10 months. I was also in the middle of refinancing my house after seeing that interest rates had finally fallen lower than my current rate, so I was going through all that crap as well. When I hit the problem with closing up the rolled leading edges of the rudder, I had had enough for a while. The "so-close-but-yet-so-far routine with the rudder, combined with all the other madness that was happening around me, was really wearing me down. So I suspended the build to give me enough time to deal with everything else and placed also focus on preparing for Oshkosh.

This trip to Airventure 2011 was special for me. My youngest son Adam decided to tag along. I sort of half bribed him to come along by offering to charter a fishing boat to do some fishing on Lake Michgan, since we would be "in the neighborhood." In the end he had a great time, and even voluntarily mentioned to me that he could not wait to go back next year. That was music to my ears, and it was the reaction that had hoped he would have.


Some pics of where I left off on the rudder
All covered up to prime the leading edge of the inside skin:

Top and middle sections rolled, bent into final pistion by hand, and clecoed into place. Right side of the lower half still needs to be rolled. Many others before me had siad to do this in sections and don't try to roll all three sections at the same time. Exactly what I did.

Close up showing that the skins seem to be  butted up against each other nicely. What you don't see is the extreme curvature of the inside skin. So at least the kerf seemed to do its job by allowing the skins to lay flat against each other.

This last shot starts to show how "over" bent the inside skin became after I coaxed the skin into the final position. so that the holes of both skins would line up more or less in along the center line of the spar. If you look back at some of the early photos takne right after I performed the bend with tube, you will notice that the flanges and holes are almost 90 degrees perpendicular to the rest of the rudder skin. IN this pic, you now see just how much further I had to bend the skins over just so that the holes of both skins would overlap so that you can apply the pop rivets to close them up. Not real happy at all with the turn out of this. In fact, this is where I stopped taking pictures. You can just see the curl of the edge of the skin, and how it is obviosly now more than 90 degrees opposed to the spar, or starting to tuck further inward. This is the problem I spoke of earlier. The combination of hand forcing the skin into position the rest of the way and the over bent edges that resulted, is what caused the difficulties with the pop rivets. I will take more pics showing the crappy but still acceptable result of attaching the leading edges with the pop rivets, adn then you will understand even better what I am talking about. I will do pics of Oshkosh next cuz rehashing this process is painful, and I need some "happy" photos to take my mind off of the crappy result I got.

Practice is over, time for the rudder roll

Here are some dimensions I used to cut the slots and drill the hole for the J bolt. I used a 1/4 inch clearance from the edge of the skin to keep the J bolt and the pipe wrenches clear of the skin. Lots of measuring going on here....

Preparing the plywood table - J bolts and rudder in place

And a slightly better shot

Did I mention a lot of measuring? These slots are so close to each other because I had to cut a different slot for the bottom section of the rudder. The distances between the middle adn top section are not quite the same as the bottom and the middle, so you have to make adjustments of you plan to do one section at a time, which I highly recommend.

Preparing to tape up the bottom section

All taped up and J bolts in place

and the other end....

and this shows the clearance from the edge of the skin...

Next shows the J bolt detail and how much I cut off. Make sure that the J bolt is high enough to clear the skin, and long enough to force the bar to stay in place.

Left side rolled. I actually rolled the top and middle sections at the same time since my pipe was long enough to do that, and then I rolled the bottom separately. Many people report that trying to do all three at once it quite difficult, since it takes a fair amount of force to bend that much aluminum at once. Better safe then sorry, so I chose to do separate sections. As you can see I am way short of the mid point, and I am frustrated at how much more work this appears that it will take to get these holes to line up so they can be riveted so I can finally be done with this assembly. The rudder is a lot of work, but if you just keep working on small portions of the assembly at a time, it will get done.

Next is something I overlooked yet again. More primer (yuck!) Thanks to Steve Riffe and a thread on VAF, I found another rudder pic from him that showed the primer applied to the outside surface of the underlying skin. This is an important thing to do since the outer skin will lay on top of this one, and once riveted will have to endure all sorts of vertical weather phenomenon, such as rain, snow, etc. Failure to prime or protect these critical areas may result in corrosion and the need to build a new rudder (double yuck). So, I ahve masked the outside edge of the underlying skin (the skin I just rolled), and will prime that edge tomorrow. Then I will proceed with the rolling of the other side of the skin, and then try to figure out how to force the edges to get close enough together to allow clecoes to be inserted in the holes, followed by pop rivets.... Hopefully I can call the rudder finished by this weekend, and then it will be on to the right elevator assembly.

Time for bed... To be continued as always....

Finishing Rivets and Preparing to Roll the Leading Edge of the Rudder Skins

Before you can start riveting the skin, you need to place a small dab of RTV sealant where the two stiffeners meet at the rear of the rudder. You know, that now impossible small space at the back of the rudder where you can't hardly do anything! Luckily, my wife works at hospital. After asking the right people, she was allowed to bring home several sizes of dosage seringes. These make the job of putting the sealant in the right place much much easier. You take the RTV from the tube, squeeze it into the seringe, and get it as close to the stiffener joint as possible, and squeeze away. You are trying to coat the very ends of each stiffener, as well as the last rivet that is set on each one, to prevent cracks from forming in the skin in this area due to vibration.

The RTV and seringe that I used:

And here is the RTV after using the seringe to put the RTV on the stiffeners:

Here is the flat sets that I used in the squeezer to set the flush rivets on the skin

I ground down the edges on the flange yoke similar to the way I did this for the other yoke. I also did it for the no hole thin nose yoke. Finally I have a set of yokes that should no longer mar up the surface of anything.

And now to set the remaining rivets on the R710 support bracket on the bottom of the rudder. Again, most folks use the pop rivets here, but IO felt up to the challenge to try to figure out a way to set these holes with the usual hard AN426 flush rivets used to attach the skin to the frame.

Step 1: Re-mount the rudder against the bench with the bottom side up so that I could access the holes in the bracket. This was quite the imaginative process, trying to figure how to secure everything correctly, without damaging the rudder. Solution was to basically take a long piece of particle board that has been my trusty drill board up to this point, set it along side the work bench, and proceed with clamping the rudder skin to it as shown in the photos:

And now we can start riveting the remaining 6 rivets on the sides of the support bracket. What I did was:
1. Used the fat man bucking bar which is short enough to fit inside the access hole of the bracket, setting it on a piece of the underlayment foam that I recently used to install my hard wod floors in the house, and slid it up into position for the forward-most rivets on both sides. I held it in place against the rivet with one hand, while holding the rivet gun with the other, adn I was able to successfully set the two forward rivets. Then I was able to use the hand squeezer with the flange yoke to set the remaining 4 rivets.

When I finished, all of the rivets on the side of the bracket were nicely set with normal hard rivets. Again, having the correct yoke and rivet sets, and a bucking bar of the correct size, allowed me to accomplish this with relatively little fuss.