Landing Light Instillation Template Tip

As is often the case when performing a task a second time, we discover that making subtle changes in the way the task is completed can make the task easier and much quicker to complete. This was the case for using the template for the right wing’s landing light. A few days ago, the hole for the landing light was cut into the W-1203R wing skin, so that part was out of the way but the template was needed once again to mark the locations for the drilling of eight holes for the lens backing strips along and the ten holes for the landing light’s mounting ribs.

Van’s instructions assume the template (which should measure 16” x 10 9/16” at the borders) is being used on a completed wing which is already riveted in place. They would have the builder cut up the template so it fits between the wing tip skin and the rivets installed on the inboard rib from the landing light hole. In my case the tip skin is not installed yet.

I decided a different and ultimately easier approach was necessary for aligning the template than the way it was done on the left wing. The procedure employed on the template for the left wing’s landing light was to attempt aligning the slippery template while holding a light inside the wing and moving the template around until the rivet hole marks printed on the template closely matched the holes in the W-1203R skin. As an added bonus to make the task even harder, because the skins were already dimpled, the cone shape of the dimples would give false alignments unless the light was placed literally directly under the rivet holes. … it was a total hassle and a time sucking abyss.

Having a few weeks to ponder a better alignment method resulted in a solution for easily aligning the template, which DOG Aviation can highly recommend for both adding a light into a finished RV-12 wing or during the wing build (as in my case). The solution is to  carefully extend the center lines used for aligning the template out to both edges of the template and draw lines on the wings through the centerlines of the rivets or holes. Lines were drawn on the wing from the very outer edge of the W-1203 wing skin, through the center line of the rivet holes on the skin Van’s wants the user to use for alignment, to a point past the template (when left intact) that ended up being the third rib inboard. This was carefully done using a small tipped sharpie marker. Next the center lines already on the template for the rivet holes to be used for the alignment were extended out to both edges of the template using a mechanical pencil with a very fine lead. The template page was then cut on the line showing the outboard edge of the W-1203 skin. Since a picture is worth a thousand words, if one looks closely at the photo below, the lines drawn on the wing and the template I’m referring to can be easily seen. This same procedure was used to mark both the top and bottom in two separate steps as Van’s suggests by marking one side then flipping the wing over and repositioning the template again for marking the other side.

                                         Aligning the template to the lines drawn on the W-1203 skin which go
                                         through the center of the line of rivet holes to be used for alignment.

This method worked great! It was a snap to align the template in this fashion and tape it in place so the eight holes for the landing light’s backing strips and ten holes for the light’s mounting ribs could be center punched and drilled. A suggestion would be to back off the spring tension so as not to dent the thin wing skin and also support the skin from underneath while center punching. After center punching, a very small diameter drill bit was used to drill lead holes, followed by drilling to #40 then final drilling to #30.

                                         With the template aligned and secured in place, a spring loaded center
                                         punch adjusted for low impact was used to mark the holes for drilling.

Using the pneumatic drill to drill out all the pilot holes to #40.

Right Wing’s Leading Edge & Flaperon Hinge Brackets Riveted

After the bottom skin riveting was completed, the right wing assembly was rolled so work could commence riveting the leading edge. The inboard portion of the right wing’s leading edge (where the wing walk doubler gets installed) is not riveted at this time nor are the aft nine rows of rivet holes on the W-1201,02 & 03 skins. As with the left wing, the aft nine rows of holes are left open to allow enough flex in the skins so the built in J-stiffeners in the top wing skins can slip into the notches in the W-1208 nose ribs.

The right wing’s leading edge is secured with Clecos and ready for riveting.

Beginning the riveting of the right wing’s leading edge, using the pneumatic rivet puller to set flush rivets.

                                           Setting the last flush rivet with the pneumatic rivet puller … note the

                                           aft nine rows are not riveted until the top skins are set in place.

 

The flaperon hinge brackets and ribs were set in place with Clecos and readied for riveting. The exact same procedure was used to rivet the flaperon hinge brackets as on the left wing. AN470AD4-4 rivets secured the hinge bracket ribs onto the rear spar and AN470AD4-6 rivets were used along the top row of the hinge bracket assembly and LP4-3 pop rivets were used in the remaining flaperon hinge bracket rivet holes.

Using the pneumatic squeezer to rivet the hinge bracket rib onto the rear spar with AN470AD4-4 solid rivets.

 

Note: In the photo above, the hinge bracket assembly was left askew … the reason for this is because, as with the left wing, access was needed so the rivet gun could be used to set the bottom rivet that secures the hinge bracket rib onto the rear spar. I elected to set that rivet using a rivet gun and bucking bar at low air pressure. Of course, a pop rivet could go here but because all the other rivets in the rear spar are solid, using a solid rivet makes for a uniform look.

                                               Using the pneumatic squeezer to set AN470AD4-6 rivets along

                                               the top row of rivet holes in the flaperon hinge bracket assembly.

 

The remaining rivet hoes that could not be reached with the pneumatic rivet squeezer had LP4-3 pop rivets placed in them. Access is very tight, even for the close quarters rivet puller, so the trick of bending the rivet’s mandrel slightly and using a wedge between the hand rivet puller and rivet head was employed for all the LP4-3 rivets that secure the flaperon hinge bracket assembly.

Close quarters rivet puller on a rivet with a bent mandrel and the wedge to offset the head of the rivet gun.

Using the close quarter rivet puller to set a LP4-3 rivet into one of the rivet holes in the flaperon hinge bracket assembly. Note the piece of scrap metal used under the rivet puller to protect the wing skin when the mandrel pops and the puller moves rapidly in …. pick a direction.

 

Right Wing Bottom Skin Riveting Completed

Riveting of the right wing's bottom skins was done using the same technique as on the left wing … starting at the center of the wing's leading edge, each row of rivets was riveted moving  alternately from the center towards the inboard and outboard edges of the wing. The removed Clecos were then moved further aft to fill in the gaps. Van’s plans require some but not all of the leading edge rivets to be left out at this time. The rivet holes on the innermost portion of the wing's leading edge where the stub spar is located are riveted now (with the exception of rivets in the wing walk area because the doubler plate is installed later), and the rest of the leading edge rivets are to be installed later when the wing skeleton is flipped over. The outboard edge of the W-1203R skin is also left unriveted at this time, as are the holes associated with the flaperon hinge bracket assemblies.

Setting the first of the bottom skin rivets into the right wing’s stub spar.

Main spar forward completed … setting the first of the many rivets into the main spar.

Bottom skin riveting nearing completion … the end is in sight just a few more rivets to set into the rear spar.

Relaxing and taking a moment to take it all in … riveting of the bottom skins onto the right wing's skeleton is completed!

 

After finishing the riveting of the bottom skins onto the right wing skeleton, with a little help from Mike (thanks for coming by on such short notice), the right wing assembly was flipped over so progress can continue tomorrow starting with installation of the flaperon hinge bracket assemblies.

All Three Bottom Skins Secured For Riveting

The W-1201R and W1203R inboard and outboard skins were aligned to the right wing’s skeleton with rivets used as aligning pins. As done on the left wing, the tabs on the W-1210 ribs (which are under the spar) had rivets placed in them by hand and then verified they were in each of the tabs before any Clecos were used to secure the skins. Next all the corners and flanges under the rear spar had rivets placed in them by hand as well to ensure positioning before Clecos were installed to secure the skins onto the right wing skeleton.  In my case, with all the dimples to help hold positioning, all that was probably overkill. But it sure does a great job of aligning the skins to the wing’s skeleton … so I can recommend that process to fellow builders who don’t have dimples to help hold the positioning of the parts.

Once the inboard and outboard skins were secured in position with some Clecos, the W-1202R bottom skin was prepared for assembly by removing the blue protective film from the rivet lines followed by a quick smoothing of the skin’s edges with the 3M foam sanding blocks.

Placing the W-1202R center bottom skin onto the right wing’s skeleton.

 

The W-1202R bottom center skin was then secured onto the right wing skeleton using the same method mentioned above followed by adding many more Clecos to all three skins. This is a slight deviation from the plans which would have the builder Cleco and then rivet one skin at a time (which I suspect is due to the small number of Clecos Van’s says is necessary to build the RV-12). The DOG Aviation procurement department purchased far more Clecos then the suggested minimum, so all three skins will be riveted at one time. Knowing from having worked on Pete’s RV-9A (which incidentally has just received an airworthiness certification from the FAA, so first flight will be any day now - congratulations Pete!!!), one can’t have too many Clecos when building an all aluminum aircraft.

Securing the right wing’s W-1202 bottom center skin onto the right wing’s skeleton by using a center punch to help align the underlying rib before placing a Cleco into the adjacent rivet hole.

All bottom skins now secured with Clecos and ready for a mass riveting session.

 

Right Wing's Bottom Skins Set For Riveting

The hope was to get to some riveting in by days end, but that was not to be because of a late afternoon start. But progress was made … the right wing’s skeleton was carried outside so the top and bottom of the main spar could be primed with zinc chromate primer to add protection where the wing’s skins will be overlapping the spar.

After the spar was primed, work began on preparing the W-1201R and W-1203R inboard and outboard bottom wing skins by removing the blue protective film along the rivet lines and fine sanding the edges of the wing skins. Also the edges of both the inboard and outboard bottom skins that will be overlapped by the W-1202 skin were prepped and primed with zinc chromate primer. All that is left to do is remove the protective film from the W-1202 center bottom skin, Cleco all the skins onto the ribs and start riveting.

Jan helping to place the W-1201R inboard bottom skin onto the right wing’s skeleton.

                                              Using a soldering iron and straight edge to remove the protective

                                              blue film from the W-1203R outboard bottom skin’s rivet lines.

 

It is amazing … the left wing took months and months to get to this point and now the right wing is to the same point in one week flat.

RV-12’s Right Wing Skeleton Ready To Skin

After having 80 degree temperatures just a couple of days ago, it was quite a shock seeing snow on the roof of DOG Aviation this morning. Braving the barely 40 degree morning in the shop the propane heater was used to quickly take the chill out of the air so progress on the RV-12 could continue in comfort.

The right wing’s stub spar was the next item up for riveting. As on the left wing, the stub spar is attached onto the six innermost W-1208 nose ribs.

Using Clecos to secure the right wing’s stub spar onto the W-1208 nose ribs for riveting.

Here again, because access was good, the decision was made to use solid rivets to attach the stub spar onto the nose ribs as opposed to LP4-3 pop rivets … AN470AD4-6 solid rivets were used in the locations where the stub spar doubler plate is located and AN470AD4-4.5 rivets were used on all the rest of the stub spar to nose rib flanges.

Riveting the right wing’s stub spar onto the W-1208 nose ribs with the pneumatic squeezer.

                                       Right stub spar riveted onto W-1208 nose ribs … now the wing skeleton

                                       is complete and ready for electrical then covering with wing skins.

The right wing skeleton was complete once the stub spar was riveted in place with the exception of the wiring … so work began on the right wing’s wiring. Once again, Heyco SB-437-5 snap bushings were substituted for the smaller snap bushings Van’s supplied for the wing’s wire run. This is because of the upgrade to the thicker three conductor 20 gauge shielded cables for both the landing light and navigation/strobe lighting. Once the cables were pulled through the snap bushings, work began on the eight pin blue electrical connector at the root of the wing.

The same technique was used as employed on the left wing’s electrical connector. A few inches of the cable’s outer coating was stripped off and the inner three wires were fished through the shield then the shield was pulled back and covered with black heat shrink tubing.

Prepared wiring ready for connector pins to be crimped onto the wires.

Using the crimping tool to crimp connector pins onto the ends of the wires.

The finished electrical connector installed onto the standoffs on the right wing’s inboard rib.

All of the pins used for wiring up the right wing’s blue electrical connector are the same pin assignments as shown in the instructions for the landing light install. However, because of the desire to have both the left and right landing lights operating in a wig-wag mode, one additional wire was added to pin three of the right wing's blue electrical connector. This wire will be used to connect the master output of the right landing light to the slave input of the left landing light … this will enable wig-wag operation (think wig-wag sync).

Wing Light Cutout Completed & Nose Ribs Installed

Assembly of the right wing skeleton was temporally halted so the landing light cutout in the W-1203R wing skin could be completed. I rather make the cut now as opposed to after the skin is riveted in place … just in case something goes wrong. My thought was to use Clecos to attach the W-1203R wing skin onto a few of the W-1208 nose ribs to keep the skin tight so it won’t flap around like the left skin did while being cut with the jig saw. This idea worked marvelously, so I can recommend it to fellow builders planning on using a jig saw as their weapon of choice for cutting the landing light cutout.

Once the tracing of the right wing's landing light cutout from the template onto the W-1203R wing skin was completed, the bottom portion of the cutout was cut first. The corners of the cutout were drilled out with a step drill to make access holes for a jig saw which was outfitted with a 24 teeth per inch blade. For the first cut, the W-1203R skin was placed on a bench with the leading edge curve hanging over the edge of the bench and the very bottom cut line was kept close to the edge of the bench so the skin would not bounce around while being cut. The bottom cut was then extended into the leading edge curve about half way on both sides.

                                                  Jan helping to hold the W-1203R skin in place while cutting
                                                  the very bottom edge of the landing light cutout with a jig saw.

After the bottom portion of the cutout was cut with the jig saw, the W-1203R skin was flipped over and Clecos were used to secure the skin onto three of the W-1208 nose ribs. This did a great job of holding the skin secure while the upper portion of the landing light cutout was then cut with the jig saw. Worked great!

               Cutting the upper portion of the landing light cutout with a jig saw while the W-1203R skin was secured
               to three of the W-1208 nose ribs. This worked great to prevent the skin from flapping around.

                           After using files to smooth the edges of the cutout and to meet the template line drawn onto
                            the skin, the 1” abrasive wheel was used to smooth the edges of the landing light cutout.

Finished landing light cutout in the W-1203R wing skin.

 

After the detour for the landing light cutout was completed, work continued on construction of the right wing skeleton and the entire lot of W-1208 nose ribs were installed today as well. As on the left wing, AN470AD4-4 solid rivets were used to install all of the ribs except the extra ribs in the wing walk doubler area which, due to clearance issues, were riveted with LP4-3 pop rivets.

 

The experienced RV-12 builder will also notice in the following photos the W-1208 nose ribs were installed in the reverse order than called for in Van’s instructions. The reason for this is … during construction of the left wing it was determined that if the assembly order were reversed, it would be much easier to use the pneumatic squeezer.

                                             Using the pneumatic squeezer to rivet one of the W-1208 nose ribs

                                             onto the right wing’s spar assembly with AN470AD4-4 solid rivets.

                                      Just a few more W-1208 nose ribs left to attach onto the right wing’s spar.

Riveting of W-1208 nose ribs onto the right wing’s spar completed ... a good days work.