RV-9A Construction Log for the ElevatorsRight Elevator
Here is what it looks like on paper. The picture is linked to a much larger file (~750k) if you want to look at some of the details.
RV-9A Construction Log for the ElevatorsRight Elevator
Here is what it looks like on paper. The picture is linked to a much larger file (~750k) if you want to look at some of the details.
Left Elevator
Here is what it looks like on paper. Note that this one is a little more complicated with the trim tab. This picture is also linked to a larger file...and here's what the elevator parts look like...
Moving along, I soon realize that I have been not tending to my camera as often as I should.These skins are different from the rudder in that they are one piece. This makes getting inside to dimple the skins a bit of a chore. I tried a few methods before I came onto one that worked well and did the least damage ... P-)
- Using the material supplied for the skin stiffeners I cut and trimmed the material and match drilled it to the skin.
- Deburred and dimpled the skin and stiffeners
Lots of pieces of scrap wood are used in the process of building a metal plane. Here I made a block to hold open the elevator skin so I could dimple the rivet holes.
See the clecoes holding on to the plywood from this side. This didn't work as well as I hoped so...
Put the dimple dies in the C-frame upside down...
Bring the base up high enough that I'm not bending the skin...
Or smashing the skin from underneath. The C-frame is resting on plywood at both ends in order to protect the skin.
The skins are resting safely in the V-blocks on the floor while I'm on to the skeleton pieces. Fluting, measuring, drilling, priming, then final assembly.
The goal is to be done with the elevators and thereby completing the empennage, by Saturday morning August 2nd, so I can brag about it at the EAA Chapter 105 Breakfast!
Okay, so I didn't get finished by breakfast.
Party on...
Wow, here it is Sunday the 10th already, I've been working on it .. honest.Catching up starting with the counter balance ribs:
Here we have the elevator counterbalance arms going together. They provide the mass balance for the elevator to help prevent control surface flutter at high speeds,
something that can really ruin yer day.
The elevator spars, one outside and one clecoed into the skin. Here the reinforcing plates are being match drilled to the spar on the left and the spar is being match drilled to the right elevator skin on the right. The triangle piece is an end rib.
Here we have one of those special tools that you can't do without. Pop-rivet dimple dies for use with a pop rivet gun.
The only way to get into some tight spaces.
Builders: The nail heads won't fit through the #40 holes in the ribs. What I did for the last three holes in each side of the rib was drill the holes out to #30 then baby-sit the #40 pop rivet dimple dies into the center of the hole before squeezing them. When you final rivet the skin to the rib you will need to use the "oops rivets" (NAS1097AD4-3.5) in these locations.
Hole sizes:
40 40 40 40 30 30 30
Dimple sizes:
40 40 40 40 40 40 40
Don't forget, AFTER you have match drilled and dimpled the skins for #40, to re-drill the holes in the skin to #30 if you use this method . Remember, these are 1097's (oops rivets) in the last four holes.
Rivets: 426AD3-3.5 NAS1097AD4-3.5 (oops rivets)
(Reminder to self: use 1097's)
Some places I did the last four rivets in the rib. This just makes it easier when you don't have to fight the tight spaces so much. YMMV
The right elevator all dressed up and ready to face the #40 drill.
..and the left elevator ready to match drill.
Notice the cutout in the left elevator trailing edge for the trim tab.
After the once again necessary tedious job of drilling each hole, deburring (all four sides of the new holes), and dimpling, the skeleton, wearing a fresh coat of alodine and zinc chromate pimer begins to take shape.
Too bad I discovered later that I was working with an old revision in the builder's manual.
After riveting on the skins it was time to back up and try to install the elevator control horn
(the thing that the stick between the pilots legs connects to)....(stop that).
That's it..bend it waaayyy back so you can drill the holes for the rivets on the control horn.
..more uses for duct tape......any port in a storm...
Oooouuch!!
It worked out in the end. Although not really the end yet as we have to close things up first. And not forget to do things inside that we have to do BEFORE we close things up.
(ahem).
...more to come, it's once again getting late and I need my beauty rest. Some of you know how badly I need that.
Oops, look what I forgot to install B-(
Yes, that momentum can leave you wanting, the trim tab hinge is supposed to be installed when you rivet the trim tab spar on the left elevator.
And of course the trim tab spar is dimpled so I have to carefully shim and clamp the hinge to the top of the dimples (after I drill out about 40 rivets). After match drilling the hinge it gets countersunk to nest the dimples.
MAKE SURE YOU HAVE THE MOST CURRENT INSTRUCTIONS not to mention looking ahead and THINKING about what you are doing!
One more time..think ahead and pay attention!
The re-completed left elevator.
Now on to the trailing edges.
You know, one of the problems with being an engineer doing a project like this is that you get these ideas. Ideas that the guys who have written the manual have probably thought of but you just have to see for yourself. The trailing edge on the rudder didn't come out so great so I was up for an alternative trailing edge method.
And since this page got really long I've given the trim tab it's own link along with the final assembly of the empennage: Trim tab and empennage assembly
I'll wrap it up early this week then it's off to the wings! The wing kit that is.
It's sort of like rounding first base, you can just about smell the leather on the bag and you've got a looong way to go.
