Santa Came Early
In the person of Rockwood Shepard, delivering my new engine this morning.
The left elevator is chugging along, slowly but fun so far. Here are the stiffeners
And the root end of the framework.
The sharp-eyed viewer will notice that there's a shear clip between the E-310 stiffener at the rib, to the trim tab mounting spar. This is a modification, intended to stiffen up that joint a bit. According to the plans, the rear spar is only attached to the inboard rib by the .016 skin.
LH Elevator Slowly Making Progress
And right now, the E-310 stiffener has been pro-sealed and riveted to the skin. The skin's drilled and dimpled, ditto the frame, and the elevator is back in its jig while the pro-seal is fully curing.
One thing I didn't expect and should have checked, is that the E-307 rear spar, that the trim tab hangs from, was slightly bent and the flanges weren't bent enough. That all took a little bit of tweaking. It wasn't hard, but the skin wouldn't lie fair until I'd rebent the flanges.
The Wd-415-1 fitting holds the trim tab cable. As designed, the flat part of the fitting stands proud of the bottom surface of the elevator. I'll need to make a hole for it to fit into so it'll be flush. These new parts will hold it. The bottom plate is .063 and so is the angle, which has a couple large lightening holes. The angle's only there because I couldn't bend that thick plate.
And yes, these do complicate the assembly sequence for the elevator.
Almost forgot to mention that I cut off the original flange of the E-310 stiffener and replaced it with a shear clip. Remember, shear clips need a minimum of two fasteners per leg. The original flange didn't let me pick up the elevator horn hole that came pre-drilled. My shear clip did. But I had to dimple the spar and the clip because the necessary second rivet was necessarily under the elevator horn.
See how even tiny changes expand?
The funny-shaped cut-out in the plate allows room for the weld on the WD-415-1.
Incidentally, the pro-sealing I mentioned is so that when I make the cut-out for the cable and the fitting, the stiffener and the skin won't separate. I have to do that before riveting the frame to the skin and these parts.
Left ELevator Ready For Trim Tab
The riveting of the left elevator went relatively smoothly. Here it is in the jig, in progress.
The warning on the blue tape is to leave open the rivet holes for the trim tab hinge. And I left the green riveting tape on too long and it was hard to remove. Not hard, just slow to remove.
The hinge cut-outs are made, and the hole in the spar for the trim cable as well.
And right now the trim tab is cut out and folded, but I haven't fit the little spar to it yet.
No excuses -- I'm slow. But you've figured that out, right?
Trim Tab Adventures
The RV-3 trim tab is .016 aluminum sheet, which has the trailing edge prefolded and which merely needs some cutting and bending. This can't be too hard, right? Hah!
The preliminary step is to make a pattern from light cardboard. The initial dimensions are given in the plans. It only took three iterations to get a pattern which would fit the already-built LH elevator.
The first trim tab had a very bad bend in the long flange that the spar attaches to. The bend was so bad that I scrapped this one and ordered a second trim tab blank.
Number two had a better bend but somehow it came out curved. I hate that. As a result, I ordered two more blanks and asked VAF for advice.
Number three went considerably better. It got far enough along to learn that the long bend needed relocating forward a bit. I also noted three issues with the angle that Van's sends for the spar. The angle is pre-bent and trimmed on the long sides.
a) The bend was curved and it was hard to straighten. But since it's .032 instead of that fragile .016, it was at least possible.
b) The top flange of the angle, to which the hinge rivets, is too narrow for the hinge. Can't widen the hinge, but no difficulty, just narrow the hinge a bit.
c) The vertical flange, which rivets to the long bent flange on the trim tab, isn't quite long enough. Or maybe the tab flange needs to be longer.
The result of all this was to make a new pattern and to make trim tab number four. This was my last blank. Fortunately it went acceptably well and is now riveted up. Here it is trial-fitted to the elevator.
Actually, riveting the hinge to the trim tab, while it wasn't hard, resulted in a somewhat wavy hinge line. I was able to bend it more or less straight and get the hinge pin in, but for the hinge to elevator assembly, I used Cleco clamps and a lot of them. I made sure that it was in solid contact before riveting, and that hinge came out pretty good.
After taking this photo, I trimmed the end of the wire and bent it so that I could safety it to the elevator's rear spar at the inboard end.
LH Elevator On Stabilizer
Finally got this assembly assembled. Seems like it took ages. This is the bottom of the left-hand side.
The slot for the trim cable isn't standard, but came about when I decided to flush-mount the cable retainer.
Thanks for the update, Dave. It's looking good!
Looks like I'll be making a third RH elevator due to a mistake that I made. I simply screwed up and get to do it over. Can't say that I'm happy about it. Please feel free to imagine the smiley of your choice here. Several of the ones on the reply sidebar apply.
Since this is the last of the empennage and I'm waiting on parts, I went to the local welding shop to get a quote on a wing jig. Remember, this is an RV-3B, so the wing jig will take a bit more abuse than if it were one of the pre-punched kits, and therefore needs to be sturdier.
Then I stopped by the hangar to bring some wing parts home.
One thing that's apparent is that I'll need some sort of container or stand or something for storing the completed empennage pieces. I don't have a good place to hang them and the guest room doesn't deserve to have them flopping all over the bed in there like they are now. Suggestions, anyone?
Also, I've been doing some minor shop rearrangement to accommodate the wings. Nothing special, just moving this and that around. The two biggest things are moving the table saw so that I'll have access to it with the wing jig in place, and shifting the band saw to where the table saw was.
I still want to hang my horizontal stab on the wall over the couch in the condo. I grew up in a house that doubled as an art gallery for my family, so why is this any different? :p
Empennage Complete, Finally!
Well, except for the tips.
Here are the pieces still on the workbench:
Of course, there's another way to look at it:
And here they are in storage in the shop rafters:
I didn't take one of those "Look, Ma! It looks like the back end of an aeroplane!" photos. Instead, I wanted to move right along.
The build log shows so many hours to date that I'd need to put them in exponential notation to record them here. Okay, maybe not. But I'm embarrassed how many hours went into this thing. Of course some of those hours went into:
One scrap horizontal stabilizer,
Two scrap right hand elevators - and they're easy; this is a mystery,
Three scrap trim tabs.
The vertical stabilizer, rudder and left hand elevator were all acceptable the first time.
I'd remove that blue film if you're planning to store them for a while up there. It becomes very difficult to remove and can trap moisture too. Moving blankets or bubble wrap will keep the scratches down, if you're worried about that. Glad to see you're making progress. I'm jealous of your bird already. What's your build site address again?
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