Back to Building = Thinking it Through....

Hopefully if you are  a fellow builder you will not have to endure the lengthy pauses I seem to experience at just about every turn in between building efforts. I am doing a horrible job of sticking to my original goal of 3-5 years for completion, but life gets in the way sometimes, and so you just keep doing what you can do I guess.

One of the problems of having lengthy delays is that it is easy to forget just exactly what you doing or what your were thinking about at the time that you stopped working on the plane. You forget where certain tools are located, and you forget the small details about certain activities.

So I spent a short time tonight just reassissing where everything was at. I know that I still have a crap load of deburring wing ribs to do, but I also realized that I still had my horizontal stab sitting on my work table - constantly getting in the way. Only problem is that I knew that I had left it there after taking it down off the wall of the garage some time back because there were still several small things that I needed to do before I hung it back up again.

- final torque the 4 mounting bolts for the center bearing/hinge.
- smooth out the cut lines where I had trimmed the edges of the HS to allow proper clearance for the elevator counter balance arms
- re-prime a couple of areas around the center joint of the HS forward spar and support angles, and also around the tips
- smooth and re-prime the area of the rear HS spar flange that had to be trimmed to allow clearance for the control horns during full down travel of the elevators.

After reviewing those items, I also realized that I still needed to drill and mount a couple of K1000-4 nut plates to accept an AN4 bolt along the web of each elevator. Here is a shot of a 3/16 inch cleco that I inserted through the large hole of the nut plate first, and then inserted the clec through the large tooling hole in the forward part of the rib web of the counterbalance support and the tip rib of each elevator.

This additional nut plate allows me to secure additional lead weight to the elevator in the event that more is needed to balance the controls when the time comes for that. You simply take a piece of lead, drill the necessary hole, and mount it to the web using an AN4 bolt and the nut plate. The subject of some controversy among builders is where to place the nut plate - on the inboard or the outboard portion of the elevator. I have chosen to mount the nut plate on the inboard side of each arm, so that any additional lead and the bolt head will be located on the outboard side of the arm (where the fiberglass tip fairing will be installed).

The reason is simple. if the bolt ever becomes loose for any reason, bot the bolt and the additional lead weight would be retained in side the fiberglass tip fairing. If either of these items are located on the inboard side of the elevator, then they could become lodged between the elevator and the horizontal stab, effectively jamming your controls and causing some very serious problems. Some builders sluff this off and decide to put the bolt and the weight on the inboard side because it is more accessible since it is not covered by the tip fairing, and this is true. I guess I view this as being safe rather than sorry. So it is a builders choice.....

I will need to enlarge the hole for the AN4 bolt (1/4 inch hole I believe). SO I will drill it out a bit, then drill the holes for the rivets, and check that little assembly off the list of to-dos.

Last item for tonight is something that I spent considerable time researching, adn I am still not 100% sure I am going with this solution, bit I think it will work.  Here is a series of pics that shows a pipe support bracket that I intend to use for securing my wiring conduit to each wing rib. I found them at HD. Unfortunately, they are just wide enough to allow the conduit to slip very easily through each hole. I figured I could place a zip tie on each side of the bracket around the conduit to hold it in place.

Using these is  a bit easier than drilling large holes in certain areas of each rib and running the conduit through the holes. The only thing I still need to check is if the aileron pushrod will clear the conduit in the last lightening hole of each rib. There are some other nylon brackets that are designed to do the same job as these, but they are more expensive and come from specific aviation suppliers. It tool me forever to find the information about them on VAF. Anyway, these brackets from HD are readily available, and aside from being a bit bulky should do the job. All you do is mark the rivet hole locations for each hole, drill them, and mount. Most use pop rivets for this which is perfectly fine. I also like the fact that they are non-conductive and therefore are perfectly suited for supporting electrical wires and such.

463 hours - Drum Roll Please......................

Got my reamer in the mail today. It was a pleasant surprise since I was not expecting it until tomorrow at the earliest. Made quick work of finishing the bolt holes in both elevator control horns. Immediately afterward I enlisted the help of my son again to remount both elevators and check for the hole alignment, freedom of movement, and alignment of the elevators with the bolt installed. The bolt went into all three holes a bit snug, but good enough to insert it by hand. So far so good...

And as for the outcome of the alignment and freedome of movement, well.......this should provide the answer:

Everything moved just as it had before - no binding, no noise, no scraping - nice and smooth on both sides with the center bolt in place.

Did the laser show one more time with the elevators clamped in trail at the counter balance arm:

Still a couple of things left to do before I consider my self done with the tail section to the point that I can move on to the wings:

Solder and heat shrink a 12 inch extension to the electric trim servo wires
Touch up primer in a few areas on the elevators
Debur the edges of the bolt holes in each control horn
Mount the electric trim servo to the left elevator (Will probably not bend the cotter pins for the clevis pins yet)
Wash and clean all the empennage parts in preparation for the tech counselor visit

Sure is nice feeling to have all the hard stuff done. My next major goal is to finish at least one of the wings by the time I go to Oshkosh this year. Also just found out today that the Steve Miller Band is coming for the opening day concert - and that is TOTALLY AWESOME!

462 hours - took the plunge and drilled the mounting holes in the control horns

Went to A&A Tradin post and got a whole bunch more drill bits so I could step drill the hole to the proper size. Only problem was that I do not have 1/4 inch reamer so I had to order one from Cleaveland tools today. This whole process was one of proper clamping, using the proper drills and drill bits, and having a very straight and snug drill guide/bushing and the proper size drill bit to use for the pilot hole. Then you end up playinv a bit of "musical elevators" by adding/removing them from the HS as needed. I did not like having to remove th left elevator after having determined that is seemed to be very well aligned with the right one with the laser level test the other night.

SO here is the beginning - drill bushing has been turned and ground down just enough with emery cloth to fit snugly inside the center bearing. I used a #27 drill bit as previously described, and my air drill for the pilot hole. Main reason for thusing the air drill is that I wanted to be able to easily verify that the drill was level. This is easier to do with the smaller, lighter air drill. ONly problem is that it lacks torque for drilling into steel, so drilling the pilot holes took forever, but it eventually worked.

The left elevator is removed from the HS so that you can get the drill in position to drill the pilot hole for the right side. the HS/elevator is turned upside down, and the counterbalance arm is clamped flush with the HS skin. ONce the pilot hole is drilled you remove the elevator from the HS, and reclamp the HS to the table to finish drilling the hole to the proper size.

Here is the pilot hole for the right elevator. Also note the clamps on both ends of the table.

My drill sequence turned out as follows:

#27 (pilot hole)
#12
Letter A
Letter C
1/4 inch reamer for the final hole.

Here is the hole after using my electric drill to upsize the hole with the bits specified above:

The air drill just does not have enough torque to upsize a hole in the steel control horns, so I switched to my electric drill, which worked out much better, I also oiled the drill bits periodically. This is necessary, and all I used is 3 in 1 oil to lubricate the bit a couple of times until the hole was drilled. In the above pic you can also see one of the many concerns about about getting this hole drilled correctly.

You need to have enough clearance from the welded joint for the shaft and the plate for the bolt head on one side and the lock nut on the other. Both of these have dimensions as follows: 7/16 inches from side to side, and 1/2 inch from point to point. Some people seem to have issues with this clearance, but it does not seem to pose a problem for me on either elevator. Plently of room for the bolt head, assuming my holes are drilled correctly, of course.

Oh yeah, if you look closely you can see that part of the weld appears to be missing. I ahve verified twice now with Vans that this is by design. Some folks on VAF from a few years ago were adamant that this was a defect in the part, and that it needed to be replaced. this small opening is provided as a relief area for the weld, as well as ensuring that there is enough room for the bolt head and the nut to sit flat against the plate of the control horn.

And here is the electric drill I used to upsize the hole.

And here is a better shot of the right elevator clamped into position for final drilling:

And here is the upsized hole for the left elevator after having removed the right elevator from the HS, reinstalling the left elevator on the HS, clamping it in its neutral position, drilling the pilot hole, removing the left elevator from the HS, and reclamping the elevator to the table for final drilling. Like I said, musical elevators.......

This one is a bit blurry but I should still have enough clearance for the bolt head or nut on this side as well.

And finally here are the drill bits I used with the aluminum drill guide/bushing:

So no clearance problems to speak of, just need to verify that the elevators will still be as closely aligned as they were before I drilled thise holes. If they are off even just a little bit I will not be happy. I'll have to wait until I get the reamer in the mail to finish the hole so I can reinstall both elevators and the bolt assembly to see how it turns out. Sure wish I would have purchased that darn 1/4 inch reamer when I bought a whole bunch of other ones a while back. I would either be crying in my beer by now for screwing up, or jumping up and down with joy shouting I AM DONE WITH THE EMPENNAGE at the top of my lungs.

Sounds like a good time to clean up the shop and finalize my plans for the wing jigs and stands.

460.5 Elevator alignment - laser level style!!

In a very short amount of time I was able to pretty much confirm that my elevators are in what I would refer to as an "acceptable" alignment with each other and with the HS, without the need for any other adjustments. I now feel pretty good about proceeding with the drilling of the holes in the control horns for the center bearing bolt attachment, and will proceed with that task tomorrow or Tuesday of this week.

Today's tasks were simply to try out a techique for the elevator alignment process that was suggested on several posts I found on VAF. THis involves using a laser level such as those found in most home improvement stores these days. Fact of the matter is I own a very good laser level that my wonderful wife had given me as a gift many years ago, which I had seldom had the opportunity to use for much of anything. In fact, I almost sold it in a garage sale a couple of years ago, and now I am glad I hung on to it.

Following are some very cool pics that frankly I was not sure would turn out very well, given the frequency spectrum of the laser light from my laser level. Turns out that most of them came out great, and I hope you think they are cool as I do. The bottom line is that this process proved beyond a shadow of a doubt to me that my elevator trailing edges are just about perfectly aligned with each other, which was a nice thing to see after applying such a precise method of alignment.

The laser level is a Laser Track from Craftsman tools. It came in a nice case, complete with two difference mounting bases for wall or free standing alignment applications, adn some funky, red colored procetive workshop-looking glasses used to enhance the laser light track in areas with high levels of normal lighting.
 I used the 3-point adjustable base shown in the pic below:

I waited until the evening hours to do this to help darken everything enought to be able to clearly see the laser light. I set the level on a card table, and moved the table with the HS and elevators closer to the garage door, which also shows the laser line quite well. With the garage door closed I started with the laser line clearly displayed on the garage, and then I slowly moved the lone down until it started to intersect with the HS. Then I made fine tuning adjustments with the adjusters in both sides of the rear of the level, until the laser line was displayed across the trailing edge of both elevators.

Here is the setup with the lights still on and the garage door closed:

And next with the laser level in position on the card table:

And next is the proof that things seem to be pretty well aligned. Here is a shot from the center (Remember to click on these pics to blow them up a bit bigger to see the details):

Next one is taken from the right side. The laser runs down the entire length of each trailing edge

And finally from the left side:

It was a little tricky getting the laser dialed in to the right spot, but once I figured out how to manipulate the adjusters I was able to get it zeroed in on the trailing edges rather well. The laser lightens up just a bit at both tips, and I actually expected this, sicne the elevators are tapered. As far as I am concerned, this process confirms what I was seeing with my manual measurements, that both elevators are actually quite well aligned, and I am happy with leaving the counter balance arms on the tips completely flush with the HS skins and leaving the control horms in their respective positions to drill the center bearing bolt attachment holes.

I spent this afternoon visiting my good friend adn fell ow builder (RV10) Mike Rettig. He is about done with his tail kit as well. Was good to talk shop and Oshkosh with someone again. He is coming along nicely on his build as well. Yes, Airventure 2012 is just around the corner! Have you made your travel plans yet?? Rest assured, just I have for the past three years, I will be there for my forth. I can hardly wait.

460 hours - finish trimming excess HS skin and check elevator alignment

Every so often during the build, probably more frequently than I am willing to admit, I have an episode of utter stupidity. Such an episode was experienced when I was trying to perform a preliminary alignment check of the elevators the other night as I described in my previous post. Short story is that I think everything is alright now, and my elevators may only be off by about 1/16 of an inch or so. So it is not as bad as I made it out to be in my previous post, and I will explain why as I work through the pics from today's activities.

I may wait to drill the center bearing hole in the control horns  until the tech counselor comes over to inspect my work, to see if I should go ahead and ajust one of the elevators to ensure that the trailing edges are completely aligned with each other.

I have a feeling that this is one of the things that may cause what some people end up describing as a heavy wing on their first flights - misaligned control surfaces or stabilizers, or both. This can result in differential lift between the two surfaces, and the plane will react to that condition accordingly. The question that I must eventually answer for myself is if a 1/16 inch difference is enough to warrant the adjustment, or if I can proceed "as is" with little or no potential impact? I am not after perfection, but I also know that misalignments ultimately result in increased drag as a result of the counter measures that are required to correct them. This, then, will also affect the overall performance of the aircraft.

So with that, here we go with today's exciting adventure....

First pic is of the elevator/HS assembly on the table. I got rid of the foam underneath, replaced that with my drill board, put  a couple of rubber tool box liners on the board, and then set the HS on top of that. I then put another piece of tool box liner over the top of the HS, followed by a long 2x4. Then it just worked out that one of my 4x4 padded blocks, standing on its end, was just about the right size to allow me to clamp it in place to keep the HS from flipping over backward.

Remember that you can click on the pic to make it bigger to see more of the details. So why did I need to do all this special clamping? Well, previously I had the HS turned upside down. The control horns are facing up in this case, making it easier to work with the entire assembly on the table without worrying about everything tipping over. Unfortunately, when everything is turned right side up, the control horns are now facing down. This makes it somewhat difficult to safely position the HS so that both elevators can swing  up and down freely, which is what I needed to do today.

You have to allow the HS trailing edge to hang over the edge of the table or bench, to allow the control horns of the elevators to acheive their entire range of motion. The elevators are then mounted completely off of the table. This raises concern that the weight of the elevators may cause the whole thing to come sliding off of the table, so I wanted to be sure to prevent that from happening.

The above pic also shows the top edge of the HS skin at the tip where the counter balance arm of the elevator is located. So I marked and drilled and cut the same way that I did for the bottom skins, and now the elevators can swing freely through their entire range of motion, limited only by the orientation of my temporary hinge pin placement (top or bottom):

The first pic above shows the completed trimming of the right side top HS skin. The clearance with the counterbalance arm per the plans is a minimum of 1/8 inches. The second pic above shows the 1/4 inch hole drilled on the left side, just prior to using the dremel cutoff wheel to cut the excess aluminum away. This pic is also a bit deceiving, because the elevator is actually in the up position, and therefore the counterbalance in the pic is tipped downward toward the floor.

The elevators are actually overbalanced right now because there is no primer, paint, or clearcoat applied, and the fiberglass tips and hardware to attach them are also not present. This actually made it easier for me to finish the top side trimming of the excess HS skin near each counter balance arm, because it kept the counterbalance arm out of the way without having to remove the elevators, like I hd to do the first time a couple of days ago, because the excess skin was still on both sides of each arm.

And another pic showing the clamping arrangement of the HS. The only other thing I still need to do to make this work perfectly is to clamp some additional blockes to the leading edge tips of each side of the HS to keep it from sliding to one side of the other while mounting the elevators. It takes a small amount of initial force to get the bearings to slide in between the hinge brackets, and this can be just enough to cause the HS to move with my current clamping arrangement.

Next are some pics that show what I needed to do to get the elevators to balance themselves in the almost "in trail" position with the counterbalance arms. I used a screw driver and a punch as counterweights and played around with the location on each elevator until they balanced.

Next is a shot of my digital smart level I used to check the range of motion on each elevator

Results from the top side were that I have plenty of range both up and down on both elevators. Plans state that the max travel is 30 degrees up and 25 degrees down. I found that the elevators would travel as far as about 35 degrees up, and I have clearance for about 32 degrees of down before the horns hit the edge of the trimmed bottom flange of the rear HS spar. At about 35 degrees up you encounter a bit of rubbing on the inboard LE of the elevator skin against the extended portion of the HS skin edge. This serves as a gap seal and seems to be quite effective, but the tolerances are very close between the HS skin and the elevator LE, so this needs to be carefully checked and adjusted if necessary.

While checking the elevator LEs during the range of motion tests, you can also see how well your elevator LE rolling exercise worked out by checking the gap line between the extended HS skin edges and the LE of each elevator. It's not very appealing seeing all the uneven bend lines in the elevator compared with the straight line of the extended HS skins. But what is important here is the freedom of movement of the control surface and clearance between all the skins, regardless of how ugly or non-linear the lines might be.

If you have achieved that, but the elevator LE roll has left some uneven or unsymetrical lines, I read a post that suggests that you can take a rubber mallet or perhaps a wood dowel and continue to reform the closed LEs enough to correct the uneven appearance. As far as I am concerned, both elevators swing freely with no binding or resistance. So unless someone more knowledgible than me tells me that I should try to "pretty up" the uneven LE rolls in a couple of places, I will probably keep them as is for now.

I was quite pleased with the movement of each elevator - very smooth and quiet and solid, with no play or slop in the hinges at all.

Next are some shots of attempting to place the elevators "in trail" by clamping the now freely moving counterbalance arms flush with the HS top and bottom skins. This was the first step in checking the alignment of the elevators.

The next step was to take something rather long that is truly straight, and lay it across both elevators, and then measure the angle or gap between the elevator skin that the bottom of the straight edge. This is done on both elevators. Then you compare the measurements. If they match, then you are golden. If not, then one elevator is not aligned with the other one, and you have some decisions to make.

Here is the pic of a piece of angle that used that is 36 inches long x 1/8 inch thick x 2 inch sides. I confirmed that this piece of aluminum is absolutely straight and true. I drew a center line on the angle, and lined it up with the cetner bearing on the HS. Note the gaps between the ends of the angle and the elevator skins on both sides.

And from the front:

This is where I got confused the other night. I originally thought that the straight edge was supposed to sit flat across both elevators. So when I saw the gap on one side, and pushed down on that side of the straight edge, I ended up with about a 1/2 inch gap on the other side, and completely freaked out, because for some stupid reason I was expecting the traight edge to lay flat across both elevators.

So, stupid me has since realized that the elevators are tapered, being wider at the root end and narrower at the tip end. So of course a straight edge is not going to lay flat across both elevators. DUH! Once I got that sorted out in my head, I took the correct measurements,and determined that I am only about 1/16 of an inch out of alignment, depending on where you place the straight edge. That may be acceptable or it may not, so we'll see.

Next is a pic of the control horns. One elevator is balanced and the other is not, which is why the horns appear to be out of alignment. I took the bolt that is supposed to be used to attach the horns to the center bearing once the holes are drilled, and laid it across the top of each horn. I am concerned that this bolt may not be quite long enough to cover the distance between the two horns,esecially after all the required washers are added to it. I believe I have also read some posts from other builders about this problem as well, so I may need to do some research to find out how to handle this one.

And lastly is a pic of the elevators in their overbalanced condition. It is really cool to see this assembly in place and moving as expected. So things are not quite as bad as I made them out to be the other night. Just another day on the build......

I will make a few more checks for alignment, and record my findings and specfic measurements. I also need to flip it over and perform the same checks from the bottom side. One note about the Avery tools temprorary hinge pins: I had to take them out and reposition them from the bottom in order to check the range of motion for the UP position. This is because the threads of the hinge pins are still a bit too long for the opening in the elevator at the tip to allow for full range of movement both up and down. The one at the root is almost completely underneath the HS and elevator skins when installed, but the one at the tip still sticks out a bit far to allow movement of the control surface on the side where the threads of the pins are sticking up.

So your choices are to grind or cut off the excess threads, or to take them out and reinstall them on the other side of the elevator to allow free movement of the surface in the opposite direction.

All for now...

458.5 hours-Turned center bearing drill guide and trimmed HS tip skins

I rRead some disturbing posts on VAF today that talk about the steps that I am about to perform on my own build. Seems that there is quite a bit of a problem with the elevator trailing edges and counterbalance skins having a bit of a twist or a misalignment problem. I called Vans today because I wanted more information to clarify their instructions which say to place the elevators "in trail" with the HS and then check the alignment of the counterbalance arms with the HS. Many builders interprest this to mean that you clamp the counter balance arms to the HS and that means that the elevator is now "in trail."

Well, I confirmed with Scott at Vans today that the true meaning of the term "in trail" is based on the extended chord line of the HS with that of the elevators. Problem is that it is difficult to determine where the chord line actually is without some reference point, which Vans does not provide in their plans. So most builders use the clamped counterbalance arms as the point where both parts should be "in trail.

Since I still had some excess skin on the HS that captures the counterbalance arms of each elevator and holds them in place, I did not need to clamp anything down just yet. At first glance it looks like everything lines up real nice, but then I got out a long piece of aluminum angle that I know is very straight. I laid it across the left and right elevators along a line that is just forward of the rear trim tab spar on the left elevator. I was shocked at how far off level the angle was. This can unfortunately only mean one thing - that my elevator trailing edges are horribly misaligned, similar to what others have experienced.

Next comes the sad story of how to resolve this problem. The possible solutions range from the following:

1. drilling out the tip rivets, repositioning the counterbalance skins and elevator skins at the tips, drilling new holes for oops rivets, and re-riveting everything.
2. Setting the elevator trailing edges so that thet are even with each other by using a laser level or other device, and leave the offset counterbalance arm "as is." This is the recommended approach.

I won't know how bad everything is until I get the excess skin of the HS tips trimmed away so that the elevators can swing freely. My fear is that the elevators are so badly out of alignment with each other that the control horns will be so badly displaced after aligning the trailing edges that there is no way that I will be able to drill the center bearing holes in each horn without running out of edge distance on at least one of the them.

So I decided to continue moving toward the inevitable by slightly reducing the aluminum drill guide bushing circumferance so it would fit inside the center bearing on the HS. It ends up being a bit too wide to fit inside the center bearing, even though it was advertised as having a 1/4 inch OD, which is supposed to be the same diameter as the bearing. I reduced it to proper size by chucking it in my drill press and turning it against a small piece of emery cloth. I did this several times, trial fitting the bushing inside the center bearing several times until it just slides snuggly through the bearing hole. This worked out fine. Here is the pic of the bushing inside the bearing with the #27 drill bit in position to drill the hole in the control horn when the time comes.

Here is a pic I promised of the clerance between the edges of the HS skin and the counterbalance arm of the elevator - it is about 1/8 inches and is fairly consistent. It also shows the amount of overlap between the forward portion of the counterbalance arm of the elevator and the tip of the HS. This excess skin needs to be trimmed away to allow the elevators to swing freely.

And here are the marks I measured for the cut on the excess HS skin. The plans call for a minimum 1/8 inch gap between the HS and the forward portion of the counterbalance arm. There will also be a 1/8 inch radius on the inside corner, similar to what I did for the removal of the material from the rear spar from the last post.

This time I decided to use the 1/4 inch drill bit to drill the hole without all the upsizing from smaller to larger bits. I started by center punching the mark for the hole, and hand turning the drill bit until the hole was established. Then I ran the drill to finish the hole.

And the finished trim job after cutting out the excess with the dremel cutoff wheel and filing the edges clean with my small file set.

I flipped the HS over and need to reinstall the elevators one more time to mark the cut lines for the other side of the HS. I will finish those tomorrow. Right now I am just sick to my stomache at the thought that these stinking elevators are probably notr aligned very well with each other. If that turns out to be the case I will no longer be a fan of computer aided matched hole concepts and will resign myself to jigging just about every assembly from here on out. Once the excess skins is removed from both sides of the tips of the HS I will be able to clamp the elevators in place, set up my laser level for the trailing edges, and the go throught steps to determine just how far out of whack everything rfeally is. Right now I am expecting somewhere between 1/4" to 1/2" offset, based on the results of my test with the angle laid across both elevators in the supposedly "in trail" position.

457.5 hours - Reamed the holes in the HS hinges and mounted the elevators -VERY COOL!

There is no better way to spend a leap day during a leap year than doing what I did today, at least as far as I am concerned anyway! This was  fun evening for change. I started by running over to A&A Tradin Post to get a #13 drill bit. I drilled out the hinge holes with this bit first, and followed it with a #12 reamer. I was mostly removing powder coating from the hole, but it did trim some metal as well. Then I trial fitted the mounting bolts in the holesv-everything fit as expected.

Then, after reading pertinent sections of Steve Riffe's builders log for this part of the empennage build, I noted that he had set the rid end bearing measurements on his elevators to 27/32 inches from the spar web to the center of the rod end bearing hole, or the bolt if you prefer. A common practice when a range of measurements is provided, i.e. between a and b, is to split the difference in the range and use that as the target value. In this case, as I stated in my previous posts, The minimum measurement is 13/16, or 26/32 inches. This is how I had set my bearings the other night. The max range on the plans is 7/8 inches, or 28/32.

Steve simply split the difference between the min and max values and set his to 27/32. After reading several recent posts from builders having problems with the LEs rubbing against the edges and rivets of the rear spar of the HS, I decided to adjust mine outward to the same measurement that Steve used for his. I have found that 1/2 of a full turn of the rod end bearing is equivalent to moving it in or out 1/32 id an inch. So I unscrewed each of them out 1/2 of a turn and that took care of it.

Here is shot of my non-scientific bolt centering method for measuring the rod end bearings:

Ya hold the bolt with one hand and measure with the other with the bolt parallel to the spar web and the rod end bearing as straight up and down inside the cutout as possible. Worked very well for me.

Next is the #13 drill bit and the #12 reamer I used to clean out the hinge holes. Sure glad I got this right the first time. That episode with the rudder still gives me nightmares.

Next are some really crappy pics of the marks and pilot holes I drilled in the bottom flange of the rear spar to provide the clearance for the downward movement of the elevators.

I used my nibbler tool to cut away the sections of the flange, and then used some small files to finish the edges and the inside radius. Turned out OK. I will apply some primer and smooth the edges with aluminum oxide sand paper, not in that order of course.

Then I enlisted the help of my son to slide the elevators onto the hinges and install the temporary hinge pins so I could get an idea of several things, including the clearance between the end of the HS and the counterbalance arm of each elevator, the clearance between the leading edges of the elevator and the rear spar of the HS, and the in trail alignment of the elevators with the contour of the HS. On all counts it looks pretty darn good to me.

Next is the alignment of the control horns. I too experienced a slight offset of the contour of both control horns, and it seems that one horn is spaced a little bit further apart from the center bearing than the other one. But other than that everything looks to be close enough to work with, so I am happy with it so far. I will have to put together the right quantity and size of washers on the center bolt to ensure that they fill the uneven gaps correctly, but this is also expected and is normal.

 

 

On this last pic you can just see the forward edge of of counterbalance skin tucked in between the top and bottoms skins on the end of the HS. This is the excess skin that has to be trimmed away. I am hesitant to do this prior to drilling the holes in the control horns for the center bearing bolt, because this seems to keep the elevators in the proper "in trail" position. I will of course also clamp them down to ensure they do not move during the drilling. I will ta to Vans tomorrow to see what the recommended procedure is.

At some point I need to trim away the excess skin so that I can check the range of motion, and also for any binding or rubbing of the elevators against the HS. Looks like I am missing some pics of the tip clearance so I will get those and post them tomorrow. I wish there was a more precise way to confirm the real "in trail" position of the elevators. I will have the same issue when I fit the ailerons to the wings. Maybe a string along the cord line or something like that.

Anyway - it is starting to look like the back end of an airplane at least. VERY COOL!