There was only one extra part I had to do for 3 of the rivets that were on the bottom edge. In order for them to fit correctly, I had to shorten the rivets so they wouldn’t protrude out.
Aside from that, I just went to town and pulled the rest of the few hundred rivets.
The last part on the riveting side was the front lip.
One of the holes on the lip has to be enlarged to fit a grommet for the wiring for the Elevator Trim Tab. I enlarged the hole using my step drill bit and then installed a snap bushing.
The last part was to install the center balance counterweight. I did some test fitting with this, but the AN3-13A bolts that one of the versions of the manual that I have mentioned are too short, so I’ll check with the factory on the proper length.
With that being said, the general assembly of the Elevator is completed:
Timelapse of the complete construction of the Elevator
With the Elevator construction completed, I’ve also finished my video timelapse of the process:
First order of business for the Elevator skin was inspecting all edges and holes and there were a few edges that needed some deburring action.
After deburring everything that needed attention, we wrapped the skins around the rib structure. Since the Elevator is a pretty big part, it was very helpful to have a second pair of hands for this.
The last thing I had to do before I can start on closing up the skin is to install the backing plate for the Trim motor inspection plate. The plans call for 1/8 rivets, but the holes were actually 3/32, so I had to first up-drill them. There’s also another small error in the plan, in that it says to rivet all 8 holes, but actually only 7 should be riveted, since the top hole is for the screw that holds the inspection plate in place.
With the wiring finished and the Antenna fitting done, I am now finally able to close up the Vertical Stabilizer and rivet the skin.
To begin, I closed up the left side of the skin and held it in place with clecos, since this is the side where the Antenna slides through the enlarged rivet hole, while on the right side I had to create the custom notch so that I can pull the skin around the Antenna.
Once that was done, I riveted on the support plate for the Antenna onto the top rib of the Vertical Stabilizer.
Now that the structure is complete, time to mount the Antenna permanently in place. Using two 20mm long M4 screws, washers and Nyloc nuts and some medium strength threadlocker I mounted the Antenna in place. Here’s the Antenna mounted in place and the wire connected to the Antenna using the BNC connector I crimped onto the wire.
Riveting the skin
With all the prep work finished, I closed up the right side of the skin, made sure everything fits correctly and clecoed it in place. There are two holes on the bottom on each side that are not riveted, but instead I have to install Rivnuts in them, so I marked out those holes, so I don’t accidentally rivet them.
There were two rivets that I had to shorten in order for them to fit flush near the Antenna. So I made a small template for the dept through a piece of wood and then shortened them accordingly.
After that, it was just a matter of pulling the many rivets on both sides of the skin to close the Vertical Stabilizer up for good.
The last part was to install the two rivnuts on the bottom on each side, so after enlarging the holes using my step drill and reaming them out using my hand reamer, I got out my rivnut puller and high strength loctite and put those in place.
With the Vertical Stabilizer completed, I then did a quick test fit and mounted it on top of the Fuselage and also attached the Rudder for a moment – almost looks like an airplane.
Before I can close up the Vertical Stabilizer skin, I need to fit the Navigation Antenna, run the wires for the Antenna and the rudder light and fit the skin including up-drilling the countersunk holes in the skin with the rib structure.
So one thing after another, first I gave a quick test fit for the skin and then drilled up all the countersunk holes.
After that was done, I went to work to fit the Rami AV-525 Navigation Antenna I’m going to use. I already fit the Antenna onto the inner rib a while ago before I built the rest of the structure, so now it was a matter of fitting it all with the skin to be able to close the skin around the Antenna.
On the left side, the Antenna comes out one of the pre-drilled rivet holes, so I just had to up-drill that to the correct size.
For the right size, the Antenna comes out offset a bit further behind, so I marked out where I needed to make the hole in the skin, then used a center punch to get a good center to drill the hole:
With the hole in place, I cut back a small notch, so that the skin can slot around the Antenna since the arms of the Antenna are fixed to the internal balun.
After all that was done, I put it all together for a final test fit:
Looks all good, so now I need to finish running the wires on the inside and then I can rivet the skin closed.
After having primed the inner surface of the Rudder skin the other day, I had all the pieces together to start working on finishing the rudder.
I attached the skin onto the structure and clecoed it into place.
Fitting the fiberglass tip
Once that was done, I went to work to fit the fiberglass tip onto the skin. I had to trim a little bit away from the bottom of the fiberglass. I made a first rough measurement, trimmed it away using my Dremel and then tried to fit it in.
After aligning it all, I did a second small pass to trim a tiny bit more, placed it into the skin again and then it looked all good.
Since the instructions are very explicit to make sure that the alignment of the rudder is perfect, I checked the alignment from all sides and it all looked good.
After all that looked good and triple and quadrupple checking that the fiberglass tip sat flush in the skin I made marks for match drilling the holes and then went to work and carefully drilled the holes into the fiberglass.
Countersinking the front of the fiberglass tip
Once that was done, it was time to countersink the holes in the front. The instructions contradict themselves – only the first 7 holes get countersunk rivets, which mathematically adds up properly to the 32 rivets (2 x 7 on the top and 2 x 9 on the bottom = 32). So after counting all the holes and re-checking the instructions and doing basic math, I decided to only countersink the first 7 holes. I sent an email to the factory yesterday and they confirmed that I was right and they’ll fix the instructions in the next iteration.
In order to finish up the Rudder, I still had to prime the inner mating surfaces of the skin, so in order to get ahead I decided to also prepare the parts for the Vertical Stabilizer and prime those as well.
After removing all the protective plastic from the parts and inspecting them, I unfortunately found that there was some dents in Rib 1, 2 and 3, so I requested replacements from the factory since those are structural parts that shouldn’t be compromised.
I still went ahead and cleaned and degreased all the other parts. Luckily it’s getting a bit warmer, so I could leave the garage door open and do the cleaning outside, to make less of a mess in the garage.
Once I was done cleaning all the parts with Simple Green, degreasing them with MEK and rubbing them down with red scotch brite, I set up my small paint booth and primed everything.
The pop dimpling tool that I ordered a few days ago arrived on Friday, so I spent some time trying it out to make sure it worked properly so I could finish adding the missing dimple to the skin and finish closing up the Horizontal Stabilizer.
After a bunch of research on them, I actually ordered 2 different tools, one is made by Aircraft Tool Supply and creates a 100 degree dimple, and the other one promises to create a 120 degree dimple, I’m not sure who exactly actually makes it, but it’s sold via Wicks Aircraft tools. The 120 degree tool from Wicks is DT-17014 and it’s supposed to screw into a G28 hand riveter.
Unfortunately the Hand Riveter I own seems to have smaller threads than the G28 hand riveter, so I decided to try it on my Milwaukee rivet gun which had the correct thread size. As I found out when I pulled with it, that ended up with too much force, so the head of the stem (which is a finishing nail) that is supposed to hold the back of the dimple in place actually deformed and got pulled into the top and got stuck.
So after that happened, I had to cut off the nail, but I couldn’t pull it out of the tool, so I got out my Dremel and cut off the top part of the bit where the deformed head got stuck in.
This way I could try to use the tool like the ATS pop dimple tool (5102D-1/8) works, which just sits on top of the rivet puller.
ATS tool on the left and the other one on the right (after I cut off the top):
So now after that modification to the tool, I tried both by holding my test piece onto the existing dimples of the Horizontal Stabilizer and determined (as expected), that the 120 degree dimple has the better fit, so I used that one to make the dimple to the skin. It came out well and the countersunk rivet sits flush like the other dimples. So for one or two dimples, this works out nice and easy and I didn’t have to go and get a dimpling press.
Riveting the skin
Once all that was said and done, I got to work and riveted the complete bottom of the left side skin. Then turned it around, removed all the Clecos from the top side one last time so I could apply the Sealant to the support plate like I did on the other side. And then I finished up riveting the top side.
Timelapse Video of Finishing the Horizontal Stablizer
And lastly as promised, here’s the timelapse video of the whole endeavor of the Horizontal Stablizer.
Today I spent another hour on riveting the Horizontal Stabilizer to finish closing up the right side.
The top has a support plate as seen below to add some reinforcement to the skin. To prevent the large metal surfaces from rubbing, the instructions call for sealant to be added between the plate and the skin before closing it up. Luckily Matthew had already clarified with TAF what the right sealant to use is, GE5050 Metal Silicone, so I had it ready for a while.
Once that was done, I closed it up one last time, ensuring a proper fit and the finished the riveting work.
So now I’m done with the complete skin on the right side and just need to do the same thing on the left side, but I need to add one more dimple on that side that was missed, so I’m waiting for a dimpling tool to finish that, which should hopefully come in the new few days.
The journey of the Horizontal Stabilizer continues with match up-drilling all the dimpled holes to fit the countersunk rivets. So basically this, multiplied by 200:
After I was done, I took off the skin one last time to clean out all the debris from the drilling and check and fix any burrs. After that it was time to put it back together again and do one last check for alignments before riveting using my self leveling laser level.
And then at last, time to start the riveting. I managed to finish the bottom of the right side, so 3 more sides to go next time.
One small problem I encountered while doing the riveting was, that because I was riveting straight down, it happened twice that some of the mandrels of the 3.2 mm rivets got stuck in the rivet gun, so I had to take it apart and push/pull out the mandrels.