Stored the Horizontal Stabilizer

I stored the Horizontal Stabilizer on the ceiling of the garage. It's plenty sturdy and I like that it's in plane sight. I know...I know, it's a lame attempt at a pun! The workbench is looking kind of lonely. Must be time for the Vertical Stabilizer (the front part of the tall tail).

Finished the Horizontal Stabilizer!

Sure was nice to read this part of the assembly manual.



Here's the completed Horizontal Stabilizer along with the intrepid builder wearing his Van's Aircraft hat. It's a small milestone but it feels good to see a part that someone would recognize as belonging to an airplane. I haven't decided where I'll store it but I'd like it to be somewhere I can see it while I'm building for a little added motivation.

Riveting Skin of HS

Here's a little video of me riveting the skin of the Horizontal Stabilizer. First, I have to remove the cleco in the hole I'm going to rivet. Next, I select a 3/32 (really tiny) rivet and put it in the hole. Then, I put a strip of riveting tape over the rivet to hold it in place and keep the rivet set from scuffing the head of the rivet. Finally, I reach inside with my tungsten bucking bar and hold it against the bottom of the rivet while I shoot the rivet from the top. Simple, just lather, rinse and repeat many thousands of times.



Here's the Horizontal Stab almost finished. It's over 8' wide so it hangs over my workbench.

Hidden Workmanship

This is just a couple of pictures of the "inside" of the Horizontal Stab. I'm getting close to buttoning it up and these parts will be permanently inside the structure. It's an odd feeling after having worked so hard getting things right and then realizing after the next steps, you'll never see them again. Really brings home how important workmanship and discipline are. If I wanted to do a fast and sloppy job, nobody would be the wiser but I'd always know and part of the enjoyment of building is doing a good job that you're proud of even if no one can see it.

New Torque Wrench

Arrh, Arrh, Arrh, new tools! This is my CDI 751 LDIN 0-75 in/lb 1/4" torque wrench that I got on ebay at a bargain. Sells for 3x what I paid. Love getting a deal but it's a tool I have to have to get it right. Many of the smaller nuts and bolts are torqued in inch/pounds (instead of foot/pounds) so you need a way to accurately measure them. The elevator hinge bracket on the rear spar right behind the wrench will be the first to get torqued. As an added bonus, the torque wrench also measures in Newton-metres so I can now fly in Europe (there will be a test on pseudovectors after lunch).

Horizontal Stab Rib Re-Do

I had another almost oops on the Horizontal Stab Ribs. I say almost because the goof technically met the requirements of AC43.13 which is the FAA bible on repairs and alterations and also MIL-R-47196A(MIL) which are the Military Specifications for rivets. I just wasn't happy with my work so I ordered replacements. Later in the build, I may just "rivet on" but I really didn't want to start off my build with "just acceptable". I don't want to let perfect get in the way of very good but I also want to be proud of my workmanship even if it's on a part that nobody will see after everything is assembled.



Speaking of oops, these are some oops rivets I ordered from Van's when I ordered the new ribs above. They're used when a hole needs to be drilled out to the next larger size but you want the head of the rivet to match the others around it. Sometimes happens when you replace a rivet and the hole is just beyond limits for the original size rivet. You can go up the the next size rivet but the head ends up being bigger. Using the oops rivets keeps everything looking "purdy".

Riveting the Horizontal Rear Spar

Here's a short video of Dexter riveting the Horizontal Stabilizer Rear Spar. He came over to return my welder and I conned him into doing some work. He's using my new 12" C-Frame back riveter. It's a brand new invention by Cleaveland Tools that makes it really easy to back rivet a universal (round) head rivet using your C-frame so everything is aligned and all you do is put the rivet gun on the top and pull the trigger. This was Dexter's first rivet and it came out near perfect.



I thought the rivets turned out well. No smileys and all the shop heads measured good with my Avery Tools rivet gauge. The new tool made it almost foolproof to get a good set on each rivet. My only experience riveting the larger -4 universal rivets was on the practice kits and this is MUCH easier.

Priming

Started priming the ribs and braces tonight. Weather was perfect for painting; 75 degrees with low humidity. Very happy with the results. Only problem I had was identifying the ribs. I marked them with a vibrating pen but it turned out that the primer is thicker than the marks. I could just barely see all but one pair and I had to remove the primer to see which was left and which was right. I turned the pen up to a higher setting for the next marks.

I'm using Napa's 7220 self etching primer. I first prepped the parts with a maroon scotchbrite pad and followed with a good wipe down with MEK.

Dimpling (Whack-a-Mole)

Finished deburring all the horizontal stabilizer parts and started into dimpling. Below is my C-frame dimpler. It has a 22" throat which is the exact size that allows you to access almost every hole in the skins of an RV. You simply place your correct size dimple dies in the upper and lower holders, align the hole in the skin with the dies, and give it a good whack with the hammer. Kinda like Whack-a-Mole, but Whack-a-Hole (for those not familiar with obscure arcade games, I added a video of Whack-a-Mole below).





This is what a dimpled hole looks like. Dimpling allows the rivet to sit flush with the skin. Making the outside of the airplane smooth makes it faster and much more fuel efficient. You wouldn't think that a small bump from a rivet would make that much difference, but at higher speeds, they add a lot of drag.

Here's the horizontal stab all dimpled.

Clecos

Here's a close-up of a cleco. It's a temporary fastener used to hold things in alignment when you temporarily assemble parts for drilling or fitting. The yellow "bootie" is optional and used to avoid scratches on shiny parts

Pop-Rivet Dimple Die

Here's one of the specialized tools I have to dimple in tight spots. It's basically a dimple die set with holes drilled through the centers. You feed a nail through one die and then through the inside hole needing dimpling. Then slip the other die over the nail on the outside of the hole and use a pop-rivet tool to pull them together.

Birthday Presents

Yeah, more tools! Shelby & Austin gave me these clamps for my birthday. Thanks a million, kid-links. Clamps are kind of like clecos, you can never have too many. Those are Shelby's hands in the picture. Luckily, I'm the one with the password to this blog so they can't post that I'm now 50.