Nov 14, 2021     13-05 - Tank Nutplate, Doubler Rivet, and Aileron Bellcrank Installation - (3.0 hours)       Category: 13 Wing Spar

Prime
11/14/2021 – 0.6 hours
[Grey Scotchbrite Pads, Bon-Ami Cleanser, Dupli-Color Degreaser, Dupli-Color Self-Etching Automotive Primer (Green – Rattle Can)]

Assemble
11/12/2021 – 1.1 hours
11/14/2021 – 1.3 hours
The inboard end of each spar has 5 spar doubler rivets and 3 nutplates that are installed in this step. I started with the AN470 (round head) rivets that finish attaching the spar doubler to the spar web. I had easy access to these rivets with the squeezer.

My next task was to install the three fuel tank nutplates on the aft side of the spar webs. I couldn't reach those with the squeezer, so I shimmed up the spar to back rivet them. There is a small snap bushing that is installed in the previous step that interfered with the back-rivet plate, so I carefully popped it out and set it aside until the riveting was complete. Back-riveting worked well in this area, and the nutplates are firmly attached.

The final assembly task in the main spar assembly is to attach the aileron bellcrank brackets to the aft side of each spar. The bottom bracket on the right spar is different than the other brackets, so you have to pay attention to ensure you put that bracket in the right spot. The spars come with the bolts for the aileron bellcranks already attached to the wing tie-down brackets. I reinstalled the bolts with the bellcrank brackets attached, and torqued the AN3 bolts to 20-25 in-lbs per section 5 of the plans. The finished spars are back in the crate until time to attach the wing ribs in the next section.
[Pneumatic Squeezer, 1/8” Cupped Squeezer Set 3X Rivet Gun, Back-rivet Set, Small Back-rivet Plate, Torque Wrench]

  Nov 12, 2021     13-03 - Spar Final Drilling and Nut Plate Installation - (17.8 hours)       Category: 13 Wing Spar

Initial Prep (Debur, Trim, Drill, and Cut)
11/3/2021 – 1.2 hours
The wing spar flanges have several holes that were not match-drilled #40 to the J-Channel in the previous step. Those holes need to be final-drilled #40. Most of the holes for nutplate rivets were already sized #40, which greatly reduced the number of holes that actually had to be final drilled.
[#40 Drill]

Final Prep (Dimple, Countersink, and Shape)
11/4/2021 – 2.6 hours
11/5/2021 – 1.7 hours
11/7/2021 – 1.4 hours
11/12/2021 – 2.2 hours
Every hole in the spar flanges, and a handful of holes in the spar web, is countersunk. The trick is that there are 4- different levels of countersinking, and you have to pay attention to countersink each hole correctly. The nutplate and rib holes that will lie underneath the fuel tank skin (inboard forward row) are countersunk for a flush rivet so the fuel tank skin can sit tightly on top of the riveted area. The nutplate holes on the aft edge of the flanges are also countersunk for flush rivets. Those nutplates are for wing access panels. The forward, outboard holes and all of the skin and rib holes in the aft row are countersunk a little deeper (.005” to .010”) for the wing skins that will connect to those holes. Finally, the attach holes in the nutplates are countersunk to the maximum outside and inside diameters specified in the plans for each type of nutplate.

In general, it's a good idea to complete the steps on each sheet in order. In this case, a step near the end of the sheet calls for spot-priming the countersunk holes. This instruction comes after the nutplates are riveted in position, which would make those holes impossible to prime. I decided to do all the countersinking, followed by priming, and then riveting the nutplates into place.

The final countersinking task occurs after the nutplates are attached to the spar flanges. The screw holes for the tank attach and access panel nutplates get enlarged, and the nutplates provide the guidance for the countersink cutter pilot to keep the holes round and concentric. The countersinks are very deep and large, and I spent a lot of time countersinking a scrap piece of aluminum to set up the microstop countersink cutter. My scrap piece was the same thickness as the spar flange (1/16”), which made it convenient to measure both the top (large) countersink max diameter and the bottom (small) countersink max diameter.
[Microstop Countersink Cage, Countersink Cutter with #40 Pilot, Countersink Cutter with #30 Pilot, Palm Drill, Digital Caliper]

Prime
11/8/2021 – 0.9 hours
11/12/2021 – 0.3 hours
Priming (or not) is generally left as a decision for the builder, but the plans for this step instructs the builder to spot prime the areas where the anodized finish on the spar was removed during countersinking. I took a rattle can of primer that didn't spray very well, and sprayed some primer into a paper cup. I then dipped a Q-tip into the primer and used that to prime the countersunk holes. I didn't scuff or clean the holes prior to priming, but I wasn't worried about the primer holding since I'd be filling the areas with anodized rivets. I just wanted enough primer to discourage future corrosion, not necessarily a thick paintable coat.
[Dupli-Color Self-Etching Automotive Primer (Green – Rattle Can), Q-tip, Paper Cup]

Assemble
11/9/2021 – 2.0 hours

11/10/2021 – 2.0 hours
11/11/2021 – 3.5 hours
Several nutplates to attach the fuel tanks and wing access panels are riveted to the top and bottom flanges of the wing spars. The nutplates are easy to access with the pneumatic squeezer, so the real challenge is how to hold the nutplates in place while setting the rivets. I initially started with a cleco in one rivet hole while riveting the other side of the nutplate. That generally worked, but there were a couple instances where I lost sight of the nutplate and damaged it with the squeezer. Those nutplates had to be removed and replaced.

The method that worked best for me was to hold the nutplate in place with a cleco clamp covering the hole for the screw. The clamp held the nutplate tight to the flange for riveting and also protected the nutplate from the squeezer. This probably isn't the fastest method, but I was happy with the results. There are also four nutplates at the outboard end of the spar web to attach. The squeezer can't reach those nutplates, but back-riveting works well for them. The nutplates for the spar web are different than the ones on the flanges, so you need to read the plans carefully!
[Pneumatic Squeezer, Flat Squeezer Set, 3X Rivet Gun, Back-rivet Set, Small Back-rivet Plate]

  Nov 03, 2021     13-02 - J-Channel - (15.5 hours)       Category: 13 Wing Spar

Initial Prep (Debur, Trim, Drill, and Cut)
10/29/2021 – 2.4 hours
10/30/2021 – 2.7 hours
10/31/2021 – 2.8 hours
11/1/2021 – 2.4 hours
11/2/2021 – 3.4 hours
11/3/2021 – 1.8 hours
Work on the wing has begun! I expect the next 9 – 12 months will be filled with challenges that are hopefully rewarded with safe and functional wings for the RV-14. The very first step provided the first minor challenge to figure out. The wing kit is delivered with 6 sections of J-Channel that are 96” (8') long and 4 sections of J-Channel that are 72” (6') long. The J-Channels are used in this step to create 8 wing box J-Channels that will be used later to attach the upper and lower wing skins. Each wing gets two long J-Channels (upper and lower for each wing) and two short J-Channels (upper and lower for each wing). The plans specify the lengths for each part, but do not state which J-Channel sections to use for the parts. The plans also don't mention that you need to make 4 more J-Stiffeners (leading edge left and right and tank left and right). The bottom line is you need to plan how to use the J-Channel sections, or you'll end up ordering more later because you won't have pieces long enough for the later steps. I looked through all of the wing plans and came up with the table below on how to get all 12 parts out of the supplied J-Channel. The trick here is to use the 8' J-Channel for the short wing box J-Channels as well as the long ones, and save the 6' J-Channels for the leading edge and tank J—Stiffeners.

Sheet // Part // Length // Part // Length // J-Channel
13-02 W-00009A-L 73 9/32” 96”
13-02 W-00009A-L 73 9/32” 96”
13-02. W-00009A-R 73 9/32” 96”
13-02 W-00009A-R 73 9/32” 96”
13-02 W-00009B-L 46 1/8” W-00009B-R 46 1/8” 96”
13-02 W-00009B-L 46 1/8” W-00009B-R 46 1/8” 96”
17-03 W-00008-L 59 3/8” 72”
17-03 W-00008-R 59 3/8” 72”
18-03 T-00003-L 54” 72”
18-03. T-00003-R 54” 72”

Match-drilling the J-Channel to the spar flanges takes time because there are a lot of holes, but isn't overly complicated. The trickiest part is getting the J-Channel in the right location and orientation, and then lining it up with 1/16” of the J-Channel above the spar flange. I saw a tip from another builder who used his rivet gauge to help find the 1/16” offset. My rivet gauge, like his, is made from 1/16” thick aluminum. Simply set the gauge on top of the flange, raise the J-Channel until the edge is even with the top of the gauge, and clamp the J-Channel in place. Take time to drill each hole, and cleco every hole as you drill. I used the rivet gauge frequently to ensure the J-Channel stayed aligned with the flange. I used BoeLube on the drill bit to keep the bit working as well as possible to create clean holes.
[Dremel with Metal Cutting Disk, Hole and Edge Deburring Tools, #40 Drill, Cleco Clamps, Spring Clamps, Hand Seamer]

  Oct 29, 2021     13-01 - Main Spar Preparation (Plans) - (1.0 hour)       Category: 13 Wing Spar

10/29/2021 – 1.0 hours
The first step for the wings involves preparing the main spars for the later steps. The spars are supplied mostly assembled, which I am very thankful for. Some of those rivets are huge – well beyond the ability of my shop to set properly! Most of the remaining work on the spars includes match-drilling and final-drilling several holes, riveting nutplates to the spars, and attaching some aileron brackets. The plans for this step are very clear, and go into a lot of detail on how to identify the right and left spars and how they are oriented (top, front, aft, inboard, outboard, …). I noted the orientation and identification on a piece of tape on each spar. I didn't see any issues in the plans or anything on the Van's website like service bulletins or changes. Time to jump in the deep end!