Elevator’s Installed

Time: 6 Hours

I got started today by retrieving the elevators from my storage so that I could install them and drill the horns. Before startinging I removed the VS so I could clean, debur, scuff and prime the forward spar attach bracket and spacer. When that was done I grabbed the left elevator and put it in place with my temporary pins. I needed to trim the elevator skins where they met the counterweights of the elevator.  I marked them and cut the skins and filed it down to a good edge.  I repeated the process on the right side. 

      Next I needed to trim the lower flange of the rear spar on the HS to allow for clearance on the elevator horns. 

 I marked the flange with a sharpie and then removed both elevators and the HS from the fuselage. I also removed the hinge so that it was not damaged during the cut.  I needed to be real careful when I cut this so that I did not damage the spar support bar underneath. I grabbed a scrap piece of .025 and drilled a hole so that I could Cleco it into position to protect the bar.  

 The cat went pretty easy with no damage, I cleaned up the corners, touched up the primer and reinstalled the hinge. 

 I put the HS back into position and rebolted it down.  Next up was the process of drilling the bolt hole through both horns of the left and right elevator for the center hinge bearing. This bolt is a 1/4″ AN4 but I would start with a #40 hole. To get the whole centered I used a drill bushing that I bought from McMaster-Carr that had an O.D. of 1/4″ and a #40 I.D.  I did have to sand down the outside edge just a little to get it to fit inside the bearing. I did this by chucking the bushing in my drillpress and using sandpaper as it turned. 

   I reinstalled the left elevator only so that I could drill its horn. The process is fairly simple, you just need to put the elevator in line with the HS by clamping the counterweight so that it is even with the HS.  

   Once it’s in place in aligned I slid the bushing back in the bearing and slid it tight up against the elevator horn.      I grabbed my 12″ #40 drillbit and drill the hole in the horn. 

 I removed the elevator and enlarged the hole with a #19 drillbit followed by my 1/4″ reamer.  

 I repeated the process on the right side.  

 I grabbed the AN4 bolt, nut and a few washers to attach the elevator horns. There is a gap between the horn and the bearing and it varies due to the welding. You just use a combination of washers to fill the gap. I ended up with 3 washers on the left and 2 and 1 thin on the right.  

 Putting these washers was made easy with my washer wrench set I bought last year.  

 With the bolt tightened down I was able to move the elevators together which was pretty cool.   

       A very common thing is to have the elevator horns be off a little as the welding process can vary from lot to lot. Mine was no different from other builders  

   The bottom of the horns is where the elevator controls connect via a rod end. The measurement is 3/8″ up and 3/8″ back to give good edge distance. You just choose the aft most horn for these measurements. That way the edge distance on the other horn is even better. In my case the right horn was the aft most one. I marked the whole and drilled a #40 hole and followed that with my 3/16″ reamer. Since there is a gap between the two horns the plans how do you make a wood drill spacer to help align the drillbit for the other horn. I grabbed a piece of oak and sanded it down to just fit between the two horns which was approximately 7/8″. I drilled a #12 hole in the wood block and slid it into place with a clamp. 

 I used that would block to drill the left horn to match the holes.  Now they are ready to connect to the elevator controls. Before that can happen I needed to put the center control tube in place. This tube will rotate left and right to control the ailerons and will house a control are in the center for a forward and aft movement to control the elevators. It was a little tough getting it into place through the center section rectangular hole. Once it was through I added the rod ends to it and temporarily bolted them in the supports.  

   It was getting late so that’s where I decided to call it a night.l after another great day in the hangar. 

Vertical Stabilizer

Time: 6 Hours

I flew home from Grand Rapids this morning and had about 7 hours before I needed to head back to the airport and fly my passengers back home and return to Chicago. So I wanted to put that time to good use in the Hangar. Now that I had the HS bolted in place I grabbed the vertical stabilizer (VS) and placed it into position, I did this ahead of step one which has you trim 9/16″ off the bottom of the VS forward spar. I have read that most people don’t need that much removed and had issues with edge distance on the lower rivets on that spar so I chose to wait to cut. You use one centered 1/8″ hole in the rear spar to grab the fuselage with and place two clamps on the forward spar at the bottom along with a spacer, attach angle and the forward spar of the HS. You have to do 3 alignments on the VS, first is the lean left and right, the second is twist left and right and third is lean forward and backward. You start with the lean left and right by picking a place to measure from on the top of the VS to a spot on the outboard edge of the HS, using the same reference point on both sides. I was easily able to get them with a 1/32″ of each other. I tightened down the clamps to hold that position so I could drill the rear spar.  

 This is where the fun begins, measuring for 3 bolt holes on the lower end of the rear spar. The bottom single hole is drilled centerline vertically and 1/32″ above a line between two rivets. This is pretty tough to line up and mark as the space is tight between the flanges of the bulkhead. I grabbed my laser that creates a line for referencing and marking. I lined it up on center of the two rivets for a marking line.  

 I used the laser line to mark a horizontal line and turned the laser vertical aligning with several holes and rivets to get a vertical line and mark the intersection of it and the horizontal line.  

 Now that I had the lower hole marked on the vertical and horizontal I needed to find the two upper hole locations. The plans call for the two holes to be 1 23/32″ above the bottom hole and 7/8″ outboard of the centerline. Again this was really tough to get measured. These holes go through the lower flange of the bottom rudder hinge plate, the spar and the tail wheel weldament. Vans make note to watch for edge distance problems with the weldment and the hinge bracket. I must have measured and examined for over an hour to make sure that I wouldn’t have any issues. I found that making sure that I had edge distance on the hinge bracket meant that I would probably have an issue with the weldment. After talking with my buddy Glen I decided that the edge distance of the weldment was much more important than the bracket as all of the waning force for the tailwheel will be transmitted to that weldment. So I lowered the line I came up with by a 1/16″ to make sure the weldament was okay. I took some deep breaths and stood back to make sure I looked at all the measurements one last time before drilling. Once I was completely sure I had them right I drilled the lower one first and put a clecko in place. I then followed with the two upper holes.  

   I checked all the holes in the inside with a flashlight and mirror and found that they all looked great. I then enlarged the holes with my 3/16″ reamer followed by my 1/4″ reamer and put the bolts in place.  

   I then moved up and drilled the two holes for the AN3 bolts, a lot easier since you just match drill and then enlarge them.  

 Next up was the two other axis that needed alignment. The lean forward and back is pretty easy as you just need a long straight edge like my long level and place it on all three rudder hinge brackets. You just need all three to touch and only requires a little movement. At the same time you need to get the twist left and right so that the rudder is aligned with the centerline of the fuselage. To do this you need a straight edge that can be clamped to the middle rudder hinge. I clamped a piece of 1″ angle and clamped it into place. I marked to spots at 10″ outboard of the rudder skin on each side. I grabbed my pink string and ran a line from the center of the instrument panel crossmember, there isn’t a center hole but rather two holes equal distance for the center of the crossmember. I ran the string in one hole and out the other. Each end of the string was then run back to the angle I clamped to the rudder hinge. I pulled the string tight and secured it so that the lines landed on the 10″ marks I made. The distance is not important as long as they are just equal. Now that you have lines that are at a know setting, crossmember to the 10″ mark on both sides, you have a reference line to measure the twist of the VS. I measured from the same place on the VS skin and got the measurements within 1/32″ 

   After tweaking all the measurements I clamped the forward spar tight and match drilled the 11 bracket holes thru the spacer and spar.  

 Remember the step I skipped for cutting the forward spar bottom? Well here is a photo of what would have been cut off and the little line where I will cut it.  

 I will match drill the 4 bolts holes tomorrow as its getting late to run the drill. I finished up the day with a little painting including the pilot and passengers control sticks and support mount.  

   Not a lot of physical work done but a lot of mental items and they are the toughest! Another great day in the Hangar!

Horizontal Stabilizer 

Time: 6 Hours

After a good Sunday breakfast this morning with my girl I got to work in the Hangar for a little work before I had to head out to fly a rare weekend trip. First up was to rivet all the parts for the two rear baggage area mods. This went pretty quick with my rivet squeezer and back riveting set. 

     Now that I had the few items that needed riveting I decided to take on the horizontal stabilizer(HS)! I was a little nervous right about this task as it’s pretty important to get it right the first time as changing drilled holes is not an option after they are drilled. First up was to find the center line of the aft deck which will end up being a reference line for the spars.  

 I then needed to get the fuselage level forward to aft and left to right.  

     I then placed the HS into position with the rear spar tight against the fuselage spar attach bars and centered on the line I drew on the aft deck. You need to give a space of 3/16″ under the rear spar which accounts for the incedence of the HS which is 0°. They suggest a 3/16″ drill bit under the center of the spar. Whit that in place I clamped the rear spar to the attach points. Now I needed to see if the HS was level in reference to the fuselage, if perfect it would be at 0°. Since the HS tappers as it goes outboard you need spacers to sit a level on. These can be of any height just as long as they are the same. I used some 3/4″ angle and turned it so that it looked like an A so the level would sit on the tip. You then need to place the spacers at the same spot on each side of the HS so your measurement will be equal.  

       I was amazed to see that it was spot on and perfect, man I love this RV-8! With everything level and perfect I really tightened the clamps and then rechecked the level. Once I was satisfied it didn’t move I matched drilled the four #30 holes thru the spar attach bars into the spar cleckoing as I went.  

   Now that the rear holes were set I needed to make sure that the HS was perpendicular to the fuselage. To do this I would take a measurement from the corner of the outside rear skin of the HS to a point along the mid fuselage on both sides. I picked a rivet hole on both sides of the middle of the fuselage and drew a line using a square at the corner of the longeron. 

   Now I had an equal reference point on both sides of the fuselage that I could measure to. When I first measured I was off by 1/16″, with a little tweak I was able to get it with in 1/32″ at 99 3/4″

   Now that everything was squared up my clamped the forward spar to the cross angle. This is where it gets a little trickier, as there are no holes to match drill from just measurements from the plans. Ok so now I need to measure in a tight space and with somewhat of a good accuracy.  Then drill a hole that is perfectly straight down thru the spar angle, spacer, fuselage angle and longeron.  The plan I came up with from help of Glen was to mark the edge of the longeron, which is the reference point for these measurements on the underside of the spar angle with a sharpie as well as the edge of the spacer.  I then removed the HS and flipped it over on the workbench to make my measurements and drill the #30 holes using my drill cup to be square.   

 I clamped the spacer in place based on the sharpie line and flush with the leading edge of the spar angle. Flipped the HS back over and used the holes I just drilled as guides to drill the spacers. I then returned the HS and spacers to the fuselage keeping everything lined up. After rechecking the measurements and making sure they were both back at 99 3/4″ I reclamped it in place.  

 I grabbed the 90° drill and put the #30 drill bit in and took a really deep breath and drilled down thru one hole trying to keep everything square using the spar angle and spacer as a guide. With one done I grabbed the #12 drill bit that I borrowed from Glen and enlarged that hole. I placed a AN3-10A bolt, washers and nut in place and tightened them down. I grabbed the tape measure and rechecked the measurements and found that they were perfect. So I drilled the opposite hole and repeated the process. Next up was the two outboard holes that go thru the longeron. Everything turned out perfect with good edge distance.  

   Whew those all turned out great so I went the aft holes and enlarged those to a #12 hole placing a bolt in place as I went.  

   Another big step today and the HS is drilled! It will come off when I get to rivet the aft top skin but now I will be able to set the elevators and controls as I go. Next up will be the vertical stabilizer (VS), another great weekend in the Hangar!

 

Rear Baggage Mod

Time: 6 Hours

Another mod that is helpful down the road for inspections and maintenance is an access panel in the rear baggage shelf. This shelf is removable by unscrewing the perimeter 16 screws but that takes time and you have to remove the entire piece to get at the substructure. So I decided to take the advice and replicate my buddy Glen’s access door. This door will allow a very quick access to the stuff underneath by a hinged panel. To start I laid out what I thought would be a sufficient size opening and looked ahead at any possible complications. The opening would give ample room to work while clearing any of the other structure around the baggage area. Once I was fairly happy with the idea I marked the opening with a sharpie and made the cut.  

   These openings seem to take for ever as I have to slowly remove material up to the sharpie line with my various files. I then flipped it over to figure out the substructure. I will have a hinge at the aft end and 3 CamLoc’s at the forward end. I will also add 3/4″ light angle around the perimeter to add rigidity and support.  

 I used my rivet spacer to layout rivets around the perimeter.  

My girl came home and wanted to try her hand at drilling so I let her match drill all the angles on the access door.  

 We finished all the mock up and drilling so I placed the shelf/door in place to see how things looked.  

  

 My push pin from Jergens Manufacturing arrived this week. I grabbed it and the passenger control stick to mark and drill.  

  

  

  

  

  

 The last thing I wanted to do today was make another rear baggage mod in the forward floor. I have planned on having and ADS-B (Automatic Dependent Surveillance) and a required transponder installed which both have independent antannaes. I plan on using a small shark fin like antennae for both down the center line of the bottom fuselage. The transponders antennae must be spaced away from other antennas to prevent interference so I will put that one aft and the ADS forward. Glen had his installed similarly and found that the ADS would land under the rear forward baggage area by the bulkhead. In reality the antennaes won’t be in the center line of the fuselage rather off either left or right based on structure that lies right in the center. So my proposed spot for the ADS fun would be to the right of center line and in between the baggage floor ribs. The baggage floor is permanently installed in this area so having access to this area would be restricted. So I decided to make a small access door just large enough to get at the two nuts the attach the antenna and the BNC cable. I laid out the door on the baggage floor using dimensions from Glen’s. I then used some .040 sheet to make it one piece perimeter.  

     I’ve been cleaned up all the edges in marked for rivets.  

 I then cut the opening in the baggage floor with my Dremel tool and cleaned up the edges. Using the plate I just made I match drilled all the holes in the baggage floor. Using the new opening I traced and cut it on new .025 sheet. A small piece of hinge was aligned and cut to fit.  All of the holes got cleaned and deburred followed by either dimpling or countersinking (where the hinge lies). I drilled the door for a flush mount CamLoc and then put all the pieces together.  

 I primed the new parts and touched up the floor.  

 Another fun day in the Hangar…off to the horizontal stab attach next!

Oil Can Fix and Flight Controls

Time: 5 Hours

I started the process of fixing the oil canning on the aft bottom skin. I bought some .032 3/4″ x 3/4″ angle from Van’s to take care of this problem. I measured and cut the angle to fit between the two bulkheads with an 1/8″ gap at each end. I cleaned up all the edges and clipped the top corners on the vertical sides to a 45°. I then used my rivet lay out jig to get a proper spacing for the rivet line. I drilled all those and then matched drilled them to the skin, cleckoing as I went. After all the holes were drilled I dimpled, scuffed and cleaned the angle. I had to use my blind rivet pulled dimple dies to get the skin holes.  I primed the angle and cleckoed it into position for when I had bucking help which came in the shape of my beautiful girl, T! This was her first time helping buck and did a perfect job and was a natural!  Did I mention I’m a lucky guy? #outtamyleague

       I finished up the work on the two sections of the pilots seat ramp along with the two ramp end ribs. They were deburred, scuffed, cleaned and primed before riveting the nutplates. I then put the parts in place to see how they looked with just a couple of screws. I Also cleckoed the floor section of the seat back hinge in place from the bottom side. Since these parts where in place I had to grab the seat back to see how it looked.  

I threw a towel in to give a little cushion so I could make a big milestone, sitting in my RV-8! 

 WOW! That was a cool feeling.  So I continued on with the progress and started working on the flight control parts. First up was to make the two tubes that would connect the pilots and passengers control sticks to the elevators. The first goes from the elevator to the bell crank and the second goes from the bell crank to the control sticks. I cut the tube for the first one with the measurements from the plans. I needed to mark marks for eight rivets around the end to hold the rod ends in place. I used a piece of paper with equal marks as a template to mark the tube.  

 I inserted the ends and marked them with the paper template. I used the drill press to drill the holes on both ends. Before disassembling them I marked the ends/tubes with a sharpie so I could put them back in the correct position. Scuffed, cleaned and primed the tubes were ready to be assembled and riveted. They went fast with my pneumatic rivet puller.  

 Next was the tube that goes from the bell crank to the controls. I used the same technique as the previous tube.  

 I turned to the bell crank itself and cleaned up the edges of all the parts followed by scuffing, cleaning, priming and riveting.  

   The control sticks are bolted into a central tube which allows the pilots and passengers to move in unison. Each control stick as a brass tube that acts as a bearing allowing it to move freely. I had to grind down these brass tubes to fit between the two side of the control column. The sides have a slight angle to them so you need to try to replicate this on the brass tubes which was a little difficult. That didn’t take too long to get both of them done and I both of them in place to see how they looked.  

   The rear stick is in two pieces and is supposed to get bolted together, however I am going to use a button pin from Jergens manufacturing which will allow the stick to be removed easily in the event that I don’t want the passenger to have access to the controls. I ordered that pin this week and should have it in a few days. Now to disassemble all these parts scuff, prime and paint the ones that will be visible.