4/5/2021 – 1.2 hours
This is the first “real” fabrication task I've come across. Previous modifications to parts have been relatively minor like separating parts and final drilling holes. This step starts with 2 pieces of Aluminum “L” angle that are to be fashioned into the Horizontal Stabilizer Attachment Bar and Rudder Stops. My first action was to transfer the dimensions from the plans to the “L” angles. I learned quickly that accounting for the thickness of the material can make a big difference in the measurements, so it is important to figure out the correct face of the “L” angle to transfer the measurements to. In this case the best faces to use are the bottom and rear of the “L” angle.
[Ruler, Sharpie)
4/8/2021 – 1.9 hours
4/9/2021 – 2.0 hours
Van's lists a bandsaw as an optional tool, and I've been fine with the Dremel and hacksaw so far. The Horizontal Stabilizer Attachment Bar and Rudder Stops, however, require a lot more precision cutting than simply separating a couple of parts or trimming off some tabs. I studied the section of “L” angle aluminum for those parts, and concluded the Dremel and hacksaw weren't going to cut it. I bought a light-duty bench-top bandsaw for this step, which was a great decision for me.
I focused on fabricating the Horizontal Stabilizer Attachment Bar first. It took some time to lay out the part dimensions again, but I managed to do that more accurately than my first attempt a few days ago. The cut across the top of the “L” angle was too thin for the saw, so I used the bench grinder and flat file for that face of the part. I then turned to the bandsaw for the angle cuts at each end across the foot and back of the part. I put some relief holes in the notch at the center of the part to provide some maneuvering room with the band saw. I then used the saw to roughly form the notch followed by the bench grinder and 150 grit aluminum oxide sandpaper to clean it up. I finished the part by rounding the sharp corners and deburred the holes and edges.
Next on the agenda was the Rudder Stops. These are also made from aluminum “L” angle. The first step was to cut the “L” angle down the center into two parts. The parts are mirror images of each other, and it is important to label the left and right parts to keep them straight. The parts have 3 angled cuts relative to the vertical face of the “L” angle. I started with the easiest 45-degree angle cut nearest to the bottom, outboard section of each part followed by the slightly less than 45 degree cut just above the initial cut, and finished with the longest cut from the top of the part to the inboard edge. The key to this step is taking the time to correctly transfer the measurements from the plans to part and measuring and marking the cuts as accurately as possible. My parts aren't perfectly identical, but they are really close and I'm satisfied with the results.
[Ruler, Sharpie, Builder's Square, Protractor, Calipers, Bench Grinder with 6” Cut-and-Polish Wheel, #10 Drill, Flat File, Bandsaw, Deburring Tools]
4/10/2021 – 1.0 hours
I finished fabricating the rudder stops by deburring the holes and edges, and countersinking the holes in the base of the rudder stops. The holes closest to the flanges are too close for the countersink cage, so I had to slowly countersink those without the cage. The final step is to prime the parts, which I will do when the weather conditions improve since I'm priming outside.
[Deburring Tools, #30 Countersink, Microstop Countersink Cage]
4/12/2021 – 1.5 hours
There is a lot of debate on priming – “To prime, or not to prime, that is the question.” OK, that was cheesy – sorry! Anyway, there are a few spots in the build where Van's says to prime. That includes all non-alclad material and the parts fabricated in this step, which are also made from non-alclad aluminum “L” angle. I've primed basically everything except the exterior skins (those will get primed when the airplane is painted), and I took this opportunity to prime all of the aft fuselage parts I've worked on so far. I waited until close to sunset for the wind to die down, but things looked good in the twilight. I'll know for sure tomorrow when I see them in the sunlight and decide if I need to touch some things up.
[Maroon Scotch Brite Pad, Dawn Dish Detergent, Dupli-Color Degreaser, Dupli-Color Self-Etching Automotive Primer (Green – Rattle Can)]