RV-3B Airframe Build Log: Step-by-Step Documentation of My Construction Process

Welcome to my in-depth RV-3B airframe build log. This page serves as a detailed diary of my experience constructing the structural backbone of the RV-3B. You’ll find step-by-step notes, practical tips, and honest reflections on both the challenges and triumphs of the process. If you’re planning your own RV-3B build or are simply curious about experimental aircraft construction, I hope this log offers valuable insights and inspiration.

Getting Started: Tools and Workspace Setup

Essential Tools I Used

Before diving in, I assembled a set of must-have tools, including: Pneumatic rivet squeezer Clecos and pliers Air drill and countersink tools Digital angle finder Sealants and brushes

Workshop Preparation

I reorganized my workshop for optimal efficiency, making sure there was ample room for the wings and fuselage to take shape. Good lighting and ventilation were also critical for both safety and precision.

Wing Assembly: Detailed Steps

Spar Construction

The build began with the spars, which form the backbone of each wing. I carefully deburred every hole, primed the components, and used clecos generously to ensure alignment before riveting.

Rib Fitting and Riveting

Attaching the ribs required absolute precision. I followed the plans closely, double-checking alignment with a digital level to prevent any warping down the line.

Skinning and Fuel Tanks

Once the ribs were secure, I began skinning the wings, working from the center out. I sealed and pressure-tested the fuel tanks early to catch any leaks before final assembly.

Fuselage Construction: Laying the Foundation

Tailcone Assembly

I started the fuselage by building the tailcone, aligning each bulkhead carefully along the centerline to maintain structural integrity.

Firewall Installation

The firewall came next, riveted in place with precision. I took extra care sealing every rivet line to prevent future issues with engine bay fumes.

Fuselage Sides and Bottom Skins

Assembling the fuselage sides and bottom skins was one of the most satisfying parts, watching the aircraft take shape in three dimensions.

Tail Section: Assembly and Alignment

Horizontal Stabilizer

Precision was essential here to ensure balanced flight characteristics. I used a combination of temporary bolts and digital measurements to set the stabilizer exactly to spec.

Vertical Stabilizer and Rudder

Both components were dry-fitted multiple times before final riveting to confirm smooth movement and perfect alignment.

Primer and Corrosion Protection

Although the original RV-3B builders often used an acrylic lacquer primer, I opted for a more modern epoxy primer for better corrosion resistance and durability. Every part was primed before assembly, adding an extra layer of protection that will pay off over the long term.

Challenges and Solutions

Rib hole misalignment: Solved by double-checking jig setups and using more clecos. Minor fuel tank leak: Repaired using ProSeal after a 24-hour leak test. Skin oil-canning: Prevented by using temporary braces during riveting. Each challenge taught me something new and helped me grow as a builder.

Final Assembly: Preparing for the Next Stages

After the main airframe components were complete, I conducted thorough inspections, verified all torque specs, and prepared checklists for the firewall-forward and avionics phases. Seeing the RV-3B’s skeleton complete was incredibly rewarding and a major milestone in the journey toward first flight.