Things done today:
- Installed rivnut and secured trim tab hinge pin
- Loosely installed bolts in elevator to HS hinge
- Went through Empennage mounting hardware and figured out where it all goes
I finally heard back from SA TAF about the trim tab hinge pin. They said go ahead with the planned install of the rivnut. So finally I could finish up the elevator. I installed the clevis to the trim servo and got it close to center. This will be adjusted later so I just put some heat shrink on the cotter pin so it doesn’t fall out and to remind me this needs to be finished. I also attached the elevator to the HS mainly to make sure everything looked good and lined up. I’ll probably leave it like this and find a place to store it as a whole assembly.
Installed the M3 rivnut and secured the hinge pin using the part I made from the end of a hinge section and an M3 screw with some medium thread lock. It holds the pin really well and the trim tab moves nice and free. I did try to install the clip on the inside of the bend, but I noticed that the pin did have a tendency to try to slip out a bit. This is because the clip and the pin were both in the same rotational plan. With the clip on the other side of the bend the pin doesn’t try to slip out of it because the rotate against each other.
Clevis is installed on the trim tab side. This will need to be fine tuned later so I didn’t bend the cotter pin. I just put a long, obvious piece of heatshrimk on it so it doesn’t fall out and get lost.
Loosely put in the AN4-5 bolts and washers on the elevator/HS hinges. The washers were a pain to get in especially the second one on the inside. I ended up using some masking tape to slip the washer in and hold it then pulled it out once the bolt captured the washer. After some practice it wasn’t too difficult to get a hinge done. I also made sure to point bolts inwards.
I installed a short 3.2mm rivet and a wire tie clip to hold the wire and connector. The rivet is covered by the access panel so you don’t see it.
A photo of the installed trim tab.
A shot of the finished HS and elevator.
Time: 3 hrs
Filled the rest of the Elevator rivets and sanding all of them. I need to order the trim servo so I can put that in and the connector ends should be here in a day or two so I can finish up the wiring. I wanted to drill the hole in the trim tab piano hinge for the safety wire, but it seems like my hinge is a bit different the other builders. I don’t really have much room to drill the hole. I might be able to drill the end of the wire that sticks out past the end of the hinge and then another hole somewhere close, then I can string a short wire between that and the hole in the hinge wire.. Not the proper way to do it, but it would at least prevent the hinge wire from falling completely out. If anyone has any ideas about how to secure the hinge wire please let me know. Some photos are below that show what I’m talking about
Elevator with rivets all sanded, now just need to finish up the electrical work.
Here’s the right side of the piano hinge. That small triangle bit of aluminum is where I’d have to put the hole for the safety wire. Although it doesn’t need to be a very large hole… a little more the 1/32″ I believe, I still don’t think there’s enough material there.
And this is the left side. There’s a little more material on this side, but it’s in the side that moves so I can’t put it there either. Maybe I can do two holes on one of those larger areas and loop it through… Hmm that might work.
Worked on the elevator today. The primer had dried for a few days on the right elevator skin so I was able to rivet it onto the skeleton. I used the technique from Pete C’s site (and Peter V,s) to make sure the elevator lined up with the HS. Seems like it lines up very lol now maybe very slightly off (1/32″ or less). I also started to fill the rivets. I’ll be riding the Trim Servo (Ray Allen T2-7A) so I can finalize the HS and Elevators.
Also used took this time to get the trim tab moving a little better
Clamped the elevator to the HS… all ready for the right skin to go on.
All finished. The new skin lined up very well and the clamps helped with the HS alignment. Now just need the trim servo and the connector ends to finish these up… oh and also need to fill and sand the rivets.
Time 2.5 hrs
Today I wanted to just check that the empennage fit the fuselage correctly and all components lined up. The idea was to check them, fill and sand the rivets and finish up the wiring so I can call it done (well minus the pitch trim in the HS for now). Well I mounted the HS on the fuselage which went fine. I then attached the elevator to the HS… ah that didn’t go so well. The ends of the elevator were a little off from the HS. I was hoping I could fix it by removing a few rivets then clamp it and rerivet. No such luck. I worked for a while and was able to get it so it was not about 1/8″ off which I was almost was going to say was good enough, but I really wanted to get it perfect. I twisted it a little more to see if I could get the frame to move a bit more under the skin and I guess I pulled a little too hard. The skin bent at the trailing edge (will have to get a photo). Well I think TAF has a skin in Torrance so hopefully it’s only a week or so set back, I’ve got plenty more to do so I’ll just move onto another project while waiting for that part.
Sling out getting some sun. The garage ceiling isn’t high enough to put the rudder on so I have to fit everything outside.
When the left side is like this
The right side is like this 😦
Clamped the left side with some wood and a bolt, then pulled most of the rivets from the right side. I was able to get it pretty close to lined up, but then I over did it.
Well now I need to wait to see if they have a skin at Torrance. I’ll try to remember to get a photo of the skin to detail my handy work :-), such a dumb mistake.
Time: 6 hrs
Finished up the elevator. The last of the empannage parts. The hardest part of this piece was the composite end pieces. When I did the test fit a few days ago it seemed like they were going to fit really well. But after riveting was finished as I fit the end pieces it seemed that no matter what I did the pieces just weren’t long enough. I ended up pushing then as far forward (lead end of elevator) as I could and then filling the trailing edge with epoxy to extend them an extra 1/8-1/4″.
I made a mold out of tape and balsa… just something easy to sand off or remove.
Mixed some 2 part epoxy and poured it into the gap.
After a little sanding
Some primer to check if it looked OK. Still a little filling needed, but the extension seems to work.
OK now on the ordering the fuselage kit
Time: 5 hrs
Prepped outer skins for riveting. Did a test fit and debur of skins.
Time: 2 hrs
Finished the vertical stabilizer today. Will have to get a picture. It came out pretty good. A few small spots that the skins do sit perfectly flat on the frame, even though I checked that all the flanges were level on the frame.
Primed the the front hinge area of the elevator. I’ve been using the protective plastic to mask the parts I don’t want to get primer on. It’s been working pretty well. Just celco the parts, use a soldering iron to trace the edge of the part then uncleco and remove the plastic.
Here’s the process I used for the hinge area on the elevator skins.
1) Celco the parts
2) Use soldering iron the trace the edge
3) Remove celcos and plastic. Now just prime. You get primer only where you need it.