Thursday, May 30, 2013

Right Flaperon Skeleton Completed

Today all of the A-1205 ribs were riveted onto the right flaperon’s spar along with the remaining three nose ribs. As with the left flaperon, all the ribs were riveted with solid rivets with the exception the two locations where a nose rib and aft A-1205 rib share the same rivet holes … in that case, just the center rivet was solid and the two outer rivets were LP4-3 pop rivets.
Using the pneumatic squeezer to attach the A-1205 aft rib onto the right flaperon spar using AN470AD4-4 rivets.
Just a few more A-1205 aft ribs left to rivet onto the right flaperon's spar.
Completed right flaperon skeleton ready for the A-1202 skins.
As with the left flaperon, a deviation is being made from the plans in that the two A-1202 aft skins will be riveted onto the A-1205 ribs before the counterbalance gets riveted in place on the outboard nose ribs.

Assembly Of Right Flaperon Continues

Now that the right flaperon’s nose and aft skins have been fully prepared for assembly, the riveting of components onto the right flaperon’s spar has begun. Before installing ribs onto the right flaperon spar, the two A-1206 pivot brackets were riveted in place onto the spar using AN470AD4-4.5 solid rivets in place of LP4-3 pop rivets.
                                              Using the pneumatic squeezer to rivet the A-1206 pivot bracket
                                              onto the right flaperon’s spar using AN470AD4-4.5 rivets.

Basically, the same procedure is being used to assemble the right flaperon that was used on the left … with one small exception on the A-1207R actuator. During the riveting of the actuator for the left flaperon, the rivet squeezer slightly grazed the actuator (even with the small diameter rivet set) because the rivet line is much closer to the fillet radius than optimum. So this time an attempt was made to alleviate any marring of the actuator’s anodizing by placing masking tape on the actuator followed by taping a thin piece of scrap metal between the rivet line and the fillet radius on the actuator.  This worked very well and the right actuator was riveted without any marring what so ever … wish I had done that for the left actuator where I now have two small mars.
                                  A piece of scrap metal used to protect the anodizing on the A-1207R actuator
                                  during riveting … note the scrapes left on the scrap metal after riveting.
Riveted A-1207R actuator without any marring of the anodizing.
The assembly order to allow for using AN470AD4-6 solid rivets on the A-1207R actuator is riveting the actuator’s outboard row of rivets (closest to the radius) first, then rivet the inboard A-1205 rib onto the actuator/spar assembly. After the riveting of the actuator was completed, the inboard A-1210R nose rib with the attached bracket was riveted onto the right flaperon spar beside the A-1207R actuator using AN470AD4-4 rivets.
Riveting the inboard A-1205 rib onto the flaperon’s right spar/actuator assembly with AN470AD4-6 rivets.
                               Using the pneumatic rivet squeezer to secure the inboard A-1210R nose rib/bracket
                               assembly onto the right flaperon’s spar with AN470AD4-4 solid rivets.

RV-12 Fuselage Kit Delivered

With all the hustle and bustle leading up to the Holiday weekend, forgot to mention the RV-12’s fuselage kit arrived at the end of last week. Van’s shipped the fuselage crate through Old Dominion freight lines. The crate appeared to be in good shape except for a little gouge in one corner.

When the driver (didn’t catch his name,my bad) noticed the bill of lading said "aircraft skins and parts", he got very excided. Apparently he enjoys model airplanes and delivering parts for a full scale airplane and seeing finished wings along with the empennage components made his day.
Maneuvering the fuselage kit onto the power lift gate for placement onto moving dollies.
Getting the RV-12 fuselage kit past the humps in the sidewalk and rolling towards the DOG Aviation production facility.
Signing the bill of lading and taking possession of the RV-12 fuselage kit. The driver said he was probably more excited about delivering parts for a real airplane than I was in receiving them. Judging by the smile on his face, that may have indeed been the case.
Will have to wait another day or two until the fuselage kit can be opened for inventory … the flaperons are currently taking up the space on both workbenches and they take up a whole lot of room.

Monday, May 27, 2013

Right Flaperon Skin Preparation Continues

Work on the RV-12’s right flaperon continued today after taking a few days away from the project to spend some time at the “southern outpost” and to attend a pancake breakfast held by EAA chapter 1077. Figured becoming acquainted with general aviation in the area would be a goof idea because at some point in the near future, the RV-12 project will require an airport to call home base … and my preference would be for that airport to have a local EAA chapter if possible.

The previously match drilled counterbalance, nose skins, and nose ribs were disassembled for deburring followed by dimpling of the nose ribs and appropriate nose skin holes.

While there is still room on the workbench, decided to jump ahead  and completely prepair  the aft skins and nose ribs. The outer edges of the A-1202A&B aft skins were dimpled last fall but the more difficult holes still required dimpling so the screw and nut method was used on the aft most holes at the narrow portion of the V and the nail and hand rivet puller method was used to dimple the remaining holes.
                                               Using a screw and nut to squeeze the dimple dies together and
                                               creating a dimple at one of the tight access holes on the aft skin.
                                 Making a dimple on the A-1202A-R aft flaperon skin with the hand rivet
                                        puller by pulling on a nail placed through the center of the dimple dies.

Once all the necessary dimples were created, the blue protective film was removed from those locations on the skins which will be overlapped so protective primer can be sprayed tomorrow.
Using one of the nose ribs as a guide for the soldering iron to melt the blue film from one of the right flaperon’s aft skins.
Pealing back the blue film from an aft flaperon skin in preparation for priming.

Thursday, May 23, 2013

Assembly Begins On RV-12’s Right Flaperon

Having the “Oregon Mirror Image” issue sorted out, work began on the RV-12’s right flaperon. The assembly procedure incorporated on the left flaperon worked out quite well, so the exact procedure will be utilized for assembling the right flaperon. That process was well documented for the left flaperon so just posting assembly photos for the right flaperon. However, the right flaperon requires flip-flopping all the nose ribs from their relative positions on the left flaperon. Think “Oregon mirror image”.
Match drilling the stainless counterweight to the holes in the A-1201C-R outboard nose skin.
Securing the A-1201A-R inboard nose skin onto the right flaperon spar with Clecos.
 Match drilling the right flaperon inboard nose ribs to the inboard A-1201A-R nose skin.

Right Flaperon & The “Oregon Mirror Image”

As previously mentioned in prior posts, the fit of the RV-12’s parts thus far has been nothing less than superb … which reflects the quality of Oregon based Van’s Aircraft’s kit components.  That said, there are places in the instructions where you end up scratching your head and say to yourself … “what”??. The flaperon instructions created one of those moments. Case in point: The instructions tell the builder to build the right flaperon as a mirror image of the left flaperon. OK, a mirror image is a reflected duplication of an object which appears “identical” but is reversed. Sounds simple enough right?

So what’s the confusion? Well, the plans have the builder rivet the A-1208 bracket onto the A-1210L nose rib. So far so good, then the assembly is riveted onto the inboard end of the left flaperon’s spar. I almost got myself into trouble because I was going to rivet the second A-1208 bracket onto the A-1210L nose rib but the only thing preventing me from doing so was my deviating from the plans with the assembly order … thought it best to wait until after the left flaperon was completed before doing any work on components for the right flaperon. That way if it was necessary to order replacement parts due to a screw up, it would only be parts for one flaperon.
Instructions for creating the A-1210L nose rib/bracket assembly.
Because a mirror’s reflection would not roll the components of the reflected image (or part mumbers) from the inside of a structure to the outside of a structure, on the surface of things one would think the second A-1210L nose rib/bracket assembly would also be placed at the inboard end of the right flaperon spar but flipped around ... NOT SO! Fortunately, a while back, time was taken to review how parts fit together and quickly realized when the A-1207R actuator was placed on the flaperon’s right spar, the actuator’s bolt hole dictates correct positioning the A-1210 nose rib/bracket assembly ... and the A-1210L assembly would not fit correctly at that location.
A-1207 L&R actuator brackets (these used to be fabricated by the builder).
The right A-1210R nose rib was tested and it appeared to fit correctly ... but that rib is inside the left flaperon about a third of the way from the inboard edge.  So it can’t be a mirror image as suggested in the instructions. Knowing the parts appeared to fit if the left nose ribs were reversed with right nose ribs, guessed that must be what Van’s wanted ... but that is not a mirror image as suggested in the instructions. So thinking I must be more daft than usual and missing something, a call was placed to Vans for clarification. Well, the positions of the right and left nose ribs are flip-flopped as I guessed and the aft ribs can be left facing outboard as on the left flaperon. However, I found it interesting Van’s builder support still considered that to be a “mirror image”. Sorry Van’s … words mean things, technically it is NOT! We agreed to disagree.
Bellow is a photo of Van’s left flaperon drawing with blue arrows pointing to the ribs that need to be flip flopped to create the “Oregon Mirror Image” followed by a photo of the correct placement of the A-1208 bracket on the left and right A-1210 nose ribs.
Left flaperon drawing - blue arrows point to nose ribs that require being flip-flopped when constructing the right flaperon.
                                           Correct placement of A-1208 brackets on the A-1210 nose ribs ... the
                                           A-1210L nose rib is on the left and the A-1210R nose rib is on the right.
Honestly, all that would have been necessary to head off any confusion for the builder would be to add another sentence in the instructions saying rivet the remaining A-1208 bracket onto the A-1210R nose rib and say the position of ALL the R & L nose ribs are flip-flopped when assembling the right flaperon. Problem solved.

The RV-12’s Left Flaperon Completed

The riveting of the flaperon skins onto the RV-12’s left flaperon skeleton went smooth ... well sort of, more on that later. Deviating from the plans, the aft skins were riveted first from the center outwards … beginning with the aft edge of the top surface and working forward towards the spar one row of rivets at a time. After the aft skins were riveted onto the ribs, the stainless steel counterbalance pipe was riveted onto the seats on the two outer most nose ribs … access was tight, but by using the close quarter hand rivet puller, riveting of the counterbalance was not an issue.
Setting the first rivet in the left flaperon aft skins - starting at the center of the trailing edge row of rivets on the top skin.

After completing the top surface, the flaperon assembly was flipped over for riveting of the bottom surface. The aft most row of rivets on the trailing edge posed a similar challenge as the aft wing tip ribs did. The rivets along this row hit the rivet already set on the other side and do not seat fully. The hand rivet puller was used to set the rivets using the same method used on the wing tips by using downward pressure on the rivet puller and slowly setting the rivet down into the hole as the handle on the squeezer is slowly depressed.
                                          Rivets set proud along the aft most trailing edge row of rivets on the
                                          bottom of the flaperon due to interference with top surface rivet.
Setting the last rivet into the left flaperon’s aft skins before the nose skins are attached.
Riveting the stainless steel counterbalance pipe in place.

Outboard nose skin almost completed.
Securing the inboard nose skin onto the left flaperon skeleton with Clecos to hold its position for riveting.
Using the pneumatic rivet puller to rivet the nose skins onto the left flaperon skeleton with flush rivets.
Presto! A completed RV-12 left flaperon riveted with mostly solid rivets inside and flush rivets outside.