Sling 4 for Matt Build Log

The night before last, I pulled my first rivets on this Sling 4 kit. With the fuselage partially completed by the previous kit owner, these weren't the first official rivets, but they were mine. Also, I did it with a hand riveter because I didn't have an air compressor. I have a pneumatic rivet gun, but no air. Yesterday (Friday) I was prepared to purchase an air compressor. Naturally, my first step was to check with my wife, who has reminded me to mention how supportive she is of this project. Thank you, Dawn, for being extremely supportive. Anyway, Dawn let me know that her mother wanted to give me something nice for my birthday (and the coinciding holiday, Christmas). She mentioned to her mother than I needed an air compressor and her mother generously paid for the one that I wanted. Thank you very much, Chris! Time to complete HS1: I set up the rear HS spar with the remaining ribs and brackets and went to work. As with the spar rivets, I used rivets in all t...

The time finally came to pull the first rivet. More on that later. One common issue I've come across reading other builder blogs is the problem of misaligned rivet holes and the need to ream holes to match. I'm sure I'll encounter that at some time, but I started with a rather simple technique to ensure rivets fit. And spars are good since you may have three or four overlapping parts and even a slightly misaligned part at any layer can make it impossible for the rivet to fit through. The picture below and left depicts using rivets only to ensure hole alignment. I made sure every rivet fits through all the parts as designed. I didn't take a picture of the next step, but it looks like the one below and right where every other rivet is replaced with a cleco. I did experiment originally with first clecoing parts together and then trying to fit rivets through. I found that rivets wouldn't fit through most of the holes due to ever so slight misalignment. I coul...

Continued work on horizontal stabilizer parts including deburring rivet holes, edges, and rounding corners. The work is slow going, but I'm happy to get the parts to the point I know the mating surfaces will be gap free. The grommets for the trim servo wire are barely big enough to fit the provided 6-core wire and too big to fit in the pre-drilled holes in the ribs. I increased the rib hole sizes to 3/8" since the caliper measurement outer diameter of the grommet measured 25/64". The grommets fit and the wire is able to pass through the new diameter. I need to go back over the nose ribs and round out the corners I skipped. After that, I'll be ready to clean and prime the horizontal stabilizer parts, but I won't be able to assemble the complete frame. One of the plates is being replaced and not due to arrive until April. I want to take a moment to describe my parts inspection/preparation process. I don't know if it's more or less than other...

The fifty 5/32" clecos that I ordered arrived and I was able to test assemble the entire horizontal stabilizer. I also got a sense how tight riveting will be from the rib side since the nose and middle ribs butt against each other in the forward spar. Having little fun with AC/DC playing in the background On to serious work: Half-way there All the way there In the first picture above, you can see the dark spar doubler plate connecting the left and right spar channels. That was the primer test piece. After 24 hours, it passed the tape test. I started with blue masking tape and realized this stuff is made to come off easily. So I applied some very sticky clear packing tape, making sure to press it down on the primer. It came off without a single speck of primer or residue. I then conducted a scratch test. The primer scratched off easier than I expected, that is, with not too much force. So, I will conduct the scratch test again after 72 hours of lay-up. A no...

I'm still waiting on tools to arrive, but I do have enough to prep and prime parts. I am going to try the following process on one part this weekend to ensure good prep work: Assemble parts with clecos and inspect for good fit, defects, or damage Remove protective film and debur. Inspect for scratches Clean parts with Simple Green Extreme Aircraft using 3M Scotch-Brite Pad 7447. Wipe down with distilled water Using nitrile gloves, wipe down with acetone Spray two coats of Rust-Oleum Self-Etching Primer and let dry for 24 hours I will assess the process by the end of the weekend and either need to adjust or be ready to move forward.

While waiting on clecos, deburring tools, cleaners, and primer, I decided to get started on removing the protective film from the horizontal stabilizer internals. The blue film comes off pretty easily, but the clear film puts up a fight. The clear film also leaves a lot of adhesive residue, which is likely due to the parts having been covered for a long time. It's also notable that along some edges where the film had been peeled back a little, the aluminum is noticeably oxidized. All parts accounted for. Removing the film from this spar doubler plate revealed a series of uniform scratches in the surface. It looks like they were created during the CNC process and cover a good portion of the part. I'm going to ask TAF about it.   Manufacturing marks in this plate. Shipment tracking indicates some of the tools I ordered will be arriving today and some on Friday. I suppose I'll start making more progress as the week continues, but I hope to get a good pace going...

It was a very productive weekend, other than royally ticking my wife off. On Friday, I hit the hardware store after work for materials to build my first two workbenches. Before starting Saturday on the workbench, however, I needed to take Christmas lights off the eves. There was a neighborhood powered lift for this purpose, but the organizer sent it back Friday thinking everyone had finished. I had to do it the old-fashioned way by climbing up to the roof and reaching over to the eves to pull the lights. To make a long story short, I fell off the roof at some point. Back to the workbenches... Here are a series of workbench photos: TAF crate setup as temporary workbench to build permanent workbenches. Building Chapter 1000 workbench upside-down per instructions. First workbench completed. Using first workbench to build second workbench. Two workbenches completed. Benches in place with build manuals and clecos on shelves below. Now it's time ...