The ribs need several holes to route various systems wiring and plumbing. I have not committed to my avionics suite, yet, so I wanted to maintain as much flexibility as possible, allow for future additions / upgrades, and minimize the number of “extra” holes. I also wanted to complete the majority of the holes before priming and installing the ribs on the main spar. I started by listing potential systems for each wing, and then reviewed the initial systems installation - Section 19 of the plans. I spent some time thinking through the routing of the pitot and AoA lines through the 8 inboard ribs. The upper aft systems hole is intended for the pitot line, and the lower aft systems hole is available for the AoA line through ribs L5 – L8. That is a good solution to get the pitot and AoA lines to the wing-mounted ADAHRS location between ribs L4 and L5, but it doesn't easily allow the static line to come into that area through ribs L1 – L4 or to allow the AoA line out to a panel-mounted ADAHRS location through ribs L1-L4. It also doesn't provide an easy way to run future wires/plumbing through the wing. I contacted Van's about adding 2 dedicated pitot and AoA holes through ribs L1 – L8, and they indicated that wasn't a problem as long as I didn't start punching holes through load-bearing parts like the wing spars or carry-through spars in the fuselage. I decided to mirror the lower-forward hole for one line near the top of the wing, and then used that hole to locate the 2nd hole at the same level near the top of the wing just aft of the forward lightening hole. That left the upper aft hole available for future upgrades and additions (similar to the right wing), and kept the Pitot and AoA lines near the top surface of the wing to minimize the chance of moisture working into the lines. Potential Left Wing Systems - Wingtip Nav/Strobe Lights - Landing/Taxi Light - Stall Warning - ADAHRS / Magnetometer - Heated Pitot with AoA - Temperature Sensor Rib L1 - LWR FWD: 1/2” (SB 500-6); WH-00011 / WH-00012 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L2 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 3/8” (SB 375-4); WH-00012 - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L3 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 3/8” (SB 375-4); WH-00012 - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L4 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 3/8” (SB 375-4); WH-00012 - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L5 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 7/16” (SB 437-4); Spare - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L6 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 7/16” (SB 437-4); Spare - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L7 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 7/16” (SB 437-4); Spare - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L8 - LWR FWD: 3/8” (SB 375-4) WH-00011 - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 7/16” (SB 437-4); Spare - Pitot/AoA: 3/8” (SB 375-4) x2 Rib L9 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 1/2” (SB 500-6); WH-00011 Rib L10 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 1/2” (SB 500-6); WH-00011 Rib L11 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 1/2” (SB 500-6); WH-00011 Rib L12 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 1/2” (SB 500-6); WH-00011 Rib L13 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 1/2” (SB 500-6); WH-00011 Rib L14 - LWR FWD: - UPR AFT: 1/2” (SB 500-6); Spare - LWR AFT: 3/8” (SB 375-4) WH-00011 Initial Prep (Debur, Trim, Drill, and Cut) 12/23/2021 – 1.8 hours 12/24/2021 – 2.0 hours 12/26/2021 – 0.8 hours The first step in the plans is to drill #19 Ground Lug Holes in the W-1010-L & -R Inboard Wing Ribs. The ground lug holes are 1/2" from the bottom of the rib and 1 1/2" from the leading edge of the rib. I located the spot for the ground lug holes and discovered there were already holes slightly larger than #19 there, so no need for any additional drilling there. The next task is to locate and drill the upper aft systems holes. The upper aft holes are 6 3/8” from the leading edge of the rib and 4 1/4" above the lower aft systems holes. I spent some time measuring the location on one of the W-1011 ribs, and made several templates from spare cardboard. The cardboard templates did not work well, so I decided to carefully measure the location on one W-1011-L and one W-1011-R rib, and then use those ribs as templates for the rest of the ribs. Unfortunately, I did not measure as well as I thought, and I ended up with very small pilot holes in all the ribs in the wrong spot. As I pondered the situation with the mis-placed #52 pilot holes, I noticed that the two inboard W-1010-R & L ribs had holes in the correct location for the upper aft systems holes. I also noticed that all of the ribs had tooling holes at the aft end that aligned, and would allow me to use the inboard ribs as templates to locate pilot holes in the correct location on W-1011-L & R ribs. I then used the W-1011-L & R ribs as templates for the rest of the ribs. I found that clecoing the aft tooling holes together, and inserting a #11 drill bit in the forward lower systems holes aligned the ribs very well to mark and drill the next pilot hole. After all of the pilot holes were drilled, including pilots for the added AoA and Pitot lines through ribs L1 – L8, it was time to consult the plans to upsize the holes to the proper diameter for the specified snap bushings. I incrementally upsized each hole to 1/4", and then used my step drill to finish each hole. [Drill bits (#52, #30, #21, #11, #10, 1/4"), Step Drill, Clamps, Rulers, Calipers, Hole and Edge Deburring Tools] Prime 12/28/2021 – 1.4 hours 12/29/2021 – 1.2 hours 12/30/2021 – 2.0 hours The next page in the plans has a place-holder for priming the parts for this step, so I decided to knock that task out while I had nice weather to clean and prime outside. The 14 ribs for the left wing (total 28 ribs for both) take awhile to work through, which has been the common theme throughout this phase of the build. I need to go back and apply a light second coat to each of the ribs (left and right) to get the even coverage that I'm looking for. Unfortunately, the weather has taken a turn for the worse, so it might be a few days before I can get back outside. I can clean the aileron torque tube bracket parts in-doors while I wait for better conditions outside. [Grey Scotchbrite Pads, Bon-Ami Cleanser, Dupli-Color Degreaser, Dupli-Color Self-Etching Automotive Primer (Green – Rattle Can)