I didn’t get to spend very much time in the shop today, but the half hour I did spend on the project was a good half hour.
I grabbed the stiffeners that I had primed on Friday night and laid (layed?) them on the left rudder skin.
Primed stiffeners, ready to be backriveted.
Then, I backriveted them.
All done.
Sorry about the lack of pictures.
116 backriveted flush rivets set.
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Empennage | Tagged: Backriveting, Priming, Rudder, skin, Stiffeners | 
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Posted by Andrew
Yes, Friday night! That means instead of being social, I get to stay home and work on the airplane. Wuhoo!
Anyway, after a good workout, I spent a couple hours in the airplane factory. First thing, I grabbed the two primed stiffeners from last night, and got them backriveted in.
#5 and #6 of 8 on the right rudder skin.
Then, I edge finished, scuffed, cleaned, and primed the last two stiffeners on the right skin. Once they were dry, I got those installed permanently, too.
#7 and #8 (two on the far left) of 8 on the right rudder skin.
I couldn’t help myself. I flipped the skin over, and removed the tape to reveal a very smooth skin. I like backriveting. The backriveting plate left some very very very small marks within about a dime sized area around the rivet heads, but I know those will polish out.
A finished right rudder skin. Those wrinkles in the vinyl in the middle where there when the skin was delivered. It didn't look like there was any damage underneath.
After spending some time admiring the right skin, I decided to finish the edges for the left skin’s stiffeners. After that, they got scuffed, cleaned, and set up on my fancy priming bench. Here they are ready for primer.
8 left skin stiffeners, ready for primer.
While those dried on one side, I decided to dive on in to the rudder skeleton. First, they have you cleco the R-904 root rib to the R-902 Spar. Tough step, but I managed.
Started on the rudder skeleton.
Then, because it was late, I had to skip the steps with the drilling and the fabricating the “shim” etc. I moved on to clecoing the spar reinforcement plates in. Here are the top two.
Fancy pants, huh?
Then, they have you grab the R-909? (tip rib) and R-912 counterbalance rib and cleco those to the spar after fluting, if necessary. It was necessary.
R-912 Counterbalance rib on the left, R-909 tip rib on the right. You can see I fluted the tip rib too much toward the aft end (top of the picture). I'll straighten it out tomorrow.
After that, they have you cleco the dreaded counterbalance skin to those two ribs. I’ve heard bad things about this step (mostly difficulty due to bad fit). Well, it was slightly difficult, but mainly due to perfect fit. If you start from the front (bottom right of the picture), everything will work out, but the fit is pretty precise. There is no slop in these prepunched kits.
The right side of the counterbalance skin clecoed on.
Then, I flipped the assembly over and clecoed on the left side of the counterbalance skin.
Left side clecoed on. (Hey, you can see my fancy fluting pliers back there.)
By then, the remaining stiffeners were dry on one side, so I shot the other side with primer and headed in for bed. (For blogging, and then bed.)
asdf
66 rivets today, all backriveted. Also, I passed 1000 rivets set today. A little bit of a milestone, although I think there are something like 20,000 rivets in the whole kit. So, I guess I’m 5% there.
Good night.
2 Comments | Empennage | Tagged: Backriveting, cleco, Priming, shoot, skeleton, skin, spar | Permalink
Posted by Andrew
I snuck home over lunch today to get a couple things done, one of which was work on the airplane loudly. First, I set up my c-frame and spent some time verifying, re-verifying, and trip verifying that I was going to dimple in the correct direction. These rudder skins are thin, and I didn’t want to make any mistakes here. I set the skins on the table with the exterior side up, and the c-frame with the male die above, pointing down, and then dimpled all the holes in the skin. Jack and Ginger (who were inside), clearly don’t like me dimpling with the c-frame and told me so with a pair of barks, each. We did get into a nice rhythm, though. [whack] Bark, bark…bark, bark. [whack] Bark, bark…bark, bark. It helped pass the time, but I hope I didn’t cause them too much stress.
My dimpling setup for the rudder skins.
After that, I flipped them over and cleaned the scuffed lines.
Skins cleaned and drying.
After drying, I shot them with some self-etching primer. I was at the end of one of the cans, and some of the stuff came out kind of splotchy, but I think it will look good after it dries. I can always lay down another coat.
The left skin after priming.
Another thing. I’ve been putting blue tape on the exterior side, then laying the skins down flat and shooting them with primer. When I do this, some primer gets into the dimple (from the underside I am priming), and kind of bounces off the sticky side of the blue tape and settles in the dimple on the finish side. Today, I made sure none of the holes were obscured; hopefully that will prevent any primer from getting on the exterior surface. I thought about taping the final rivets in the dimples, since that is the next step with the skins anyway, but I am not sure about using self-etching primer on unset rivets, then setting them. I have never seen that done before, and I don’t want to be the first guy to try. I’m sure I would have been okay, but the other way seemed to work fine.
And the right skin after priming.
After work, I put rivets in all of the dimples, taped them up, and flipped the skins over to lay the stiffeners in. One note, since I am using the tank dies, the rivet sizes must be lengthened in some places. All of the stiffener rivets were too short before setting, so I am going to substitute AN426AD3-3.5 rivets for the AN426AD3-3s called out in the plans. Except for the aft-most rivet in each row. The construction manual tells you to make sure you set this rivet fully, so I’m going to leave the shorter one in there.
See these rivets? They look okay, until you put the stiffener in
Once you get the stiffener in, you can see they aren’t the recommended 1.5 times diameter. I’m also a little concerned that the dimpled holes are a little big for the rivets. I didn’t notice this on the other components using the tank dies. Hmm. I’m going to look around and see if anyone else has encountered this.
Not long enough. (TWSS)
I was moving along merrily until I got to this hole. Doh!
Forgot to dimple this hole. I had to break out the c-frame just for this one lonely hole.
After I got all the rivets in and taped, I flipped the skin over.
These rivets will be long enough.
Then, one by one, I final trimmed the stiffeners (snipped the 90° corners off with the snips) and laid them in to see what it would look like.
asdf
A solid hour and a half. After edge prepping and priming the stiffeners, I should be ready to install the stiffeners permanently.
Leave a Comment » | Empennage | Tagged: C-frame, Dimpling, Ginger, Jack, Priming, skin, VS | Permalink
Posted by Andrew
Well, with the vertical stabilizer safely in the airplane storage room, it’s time to get started on another part. Next up, the (infamous) rudder. There are a lot of steps on the rudder that give a lot of builders a lot of trouble. I am confident, but will continue to use other sites on a daily basis before doing any work that evening. That’s worked out well for me so far, so I’m going to keep at it.
First thing’s first, the ceremonial plans change. I still keep the plans on my second workbench. Maybe someday I’ll find a place to actually hang them up.
Drawing 7. The Rudder. (Cue dramatic music.)
I spent a little time trying to figure out whether I will do the stiffener-to-skin dance on both sides at once, or just one side. You can see below that if I had another longer piece of MDF and maybe took my vise off the bench, I could set the skins on opposite corners and maybe do them at once, but I think I’ll just do one at a time, making sure I can reuse the holes I plan to drill into the table. (Drilling, and then clecoing, the stiffeners to the skins all the way into the table will allow me to keep everything very steady. Sounds like a good plan to me, and is pretty much standard given that Van’s suggests doing so in the construction manual.)
I'll have to do one skin at a time. I don't want to get too crowded, and I am not overly concerned with building efficiency.
First step in the manual is to start on the stiffeners. I fished out the bundle of stiffeners (there are two bundles, one set for the rudder, and one set for the elevator) and studied the plans. For the back side of the stiffeners (with the shallow angle on the right side of the picture below), these are the final cuts, so I need to be careful. For the front side (you can see a little of the front of a stiffener on the left in this picture), only 2 of the 16 stiffeners will be to full length, so the other 14 can be rough cut until I can mark them to final size per the note at the tot of this picture.
Stiffener Trim detail, drawing 7.
Next, I headed inside to sit myself down at the table so I could watch the UNC vs. GT game. I know some of you are panicking right now, but please calm yourselves. While it appears that my winerack is empty (OH MY GOD, NOOOOO!), that is really our third winerack. Rest assured that our two primary wineracks are stocked satisfactorily.
Is that an empty winerack? Don't worry, the hooch is stored in another rack.
Anyway, here’s the stiffener bundle I’m about to break open.
R-915. (I can't think of a funny caption this morning, so all you get is the part number.)
I broke open the bundle and started snipping from center hole to center hole. After a few stiffeners, I started biasing the cuts to the sides of the holes, but only where I was sure that I was going to have to remove more metal later. Here you can see that on the top part of the cut, I’m lined up with the left side of the slot.
Snip snip.
I included another picture of the angle cut for the front end of the stiffener. Remember, only two of these cuts are for real, as the next step is to chop off varying lengths of stiffener from the front to match up with the pre-drilled holes in the skin.
Snippity Snip snip.
Here’s a rough cut for the front end. See how I am going to have to remove more metal because of the notches. Might as well get closer on the first cut. That’s why I started biasing the cuts to one side after the first few.
The front end of the first stiffener.
First 8 front ends done.
Yikes, those are going to need some edge finishing.
All 16 stiffeners’ front ends done.
That's a spicy stiffener.
Next, I used an admittedly fat sharpie to draw the required cut lines on the aft ends of each of the stiffeners.
Lines drawn, back to snipping.
And here I am using the snips to cut that longer line. Snips aren’t perfect for this task, since they bend the metal, but if you work them correctly, they will only bend the piece you are cutting off. There is kind of a rocking motion you have to feel with each cut. You’ll get it when you try.
Snipping the aft end.
Here’s the first one, done.
I'm a little camera happy today, don't you think?
Then, I finished up the other 15, and was left with these scraps. If I had even the slightest hint of an artistic bone in my body, I would make some comment about how these resulting spirals are king of cool. But I don’t, so I won’t.
Scrap from the latest cuts.
All 16, ready to be devinyled.
Done with those cuts.
Starting to devinyl…
This is going to take forever.
I’m glad I did the devinyling inside. When the vinyl is warm, it comes right off.
Holy crap that's a lot of blue v-......WHOSE TOES ARE THOSE AND HOW DID THEY GET IN THE PICTURE!?
Next, I headed outside to put everything away, but couldn’t resist setting the stiffeners out on the skins.
I'll need to trim some of these, don't you think?
For now, I just drew a thick marker line along the front spar holes. If I cut along these lines, they will still be too long, but at least now I can figure out which hole will be the most forward hole and then use the plans-suggested 1/4″ measurement to draw a nicer cut line.
8 of the 16 stiffeners, ready for final cutting.
One hour of camera-happy warm environment work tonight. Sorry about your bandwidth.
Leave a Comment » | Empennage | Tagged: Construction Manual, Devinyl, Empennage, Front spar, MDF, Plans, Rudder, skin, Snips, Stiffeners, Van's, Vinyl, VS | Permalink
Posted by Andrew
I’m writing this on Monday for Friday night’s work, so we’ll see how much I can remember.
After a couple minutes of clecoing on the right side of the VS skin, I got started riveting. First, I set every other rivet along the VS-702 front spar and the VS-707 middle rib.
Left skin on the bottom, right skin on the top. That crazy long cleco keeps sneaking into the pictures.
After rivting the front spar and ribs to the skin, here’s an interior picture.
Lower interior of the vertical stabilizer.
Here’s a picture of my “every-other-rivet” style. It works well.
Ready for the remaining rivets.
There are 39 rivets (not counting the tip and root ribs) for the front spar and middle ribs. After setting these 39, I’m ready to pull off the blue vinyl from the interior.
Starting to look pretty. So is your face.
Another rivet picture. (I’m not sure I got these in the correct order…Hmm.)
VS shop heads.
More rivets.
More shop heads.
<sigh>
<yawn>
Had enough yet?
Even more shop heads.
Alright, now I get to start removing the blue vinyl. This is where the gravy is. After all that prep work and riveting, you get to remove the vinyl to reveal a beautiful shine on the inside. I can’t wait to do this on the exterior skin (just before polishing). Flash on for visibility.
Starting to remove the blue vinyl.
I left the flash on for this one so you could see inside.
Inside the lower bay of the VS.
And the upper bay.
Upper bay of the VS.
After removing all of the vinyl, I moved on to riveting the tip (VS-706) and root ribs (VS-704 and VS-705) to the skin. All was going well, until I got the front of the root rib.
Anyway, for some reason the skin wasn’t sitting well on the rib. I later determined it wasn’t interference, just the natural curve of the rib.
The lower right side of the VS skin wasn't sitting very well on the root rib.
My solution? Use a tape-covered clamp to squeeze them together.
Alright, let's set this rivet.
That did the trick. Who’s next?
Looks perfect now.
Here I am riveting some of the rest of the root rib. I was very careful to not rivet the 6 holes on each side the instructions tell you to leave open for the empennage fairing. I probably won’t use all 6, but I can always squeeze these later, so why close any metaphorical doors?
In the middle of squeezing the root rib.
Here’s the VS (except the rear spar) all riveted together. Notice the 6 clecos in the holes to leave open.
Where's that rear spar?
I inserted the rear spar and started setting rivets. All was going perfectly, until I realized that most of the rivets couldn’t be set because of conflicting shop heads on the rear spar. I had tried two rivets that were close to having enough clearance, and I messed both of the shop heads up. Here’s one.
Bad rivet shop head there in the middle. Obviously.
And here’s the other.
Another bad shop head there on the left. See the cleco in the middle of the picture. The rivet that will go in that hole doesn't have a lot of room to be bucked.
I gave up on any other rivets that would be close with the squeezer. I’ve been doing so well recently with the gun and bucking bar, that I’ll just wait till I can make loud noises and set them with the gun.
Where I left off for today. I'll figure out how to set the remaining rear spar to skin rivets sometime next week.
One and a half hours today. 135 rivets set; some shot, some squeezed. Only a few will have to be drilled out later. Good night tonight. Hopefully next week, the dogs will get some directional stability.
Leave a Comment » | Empennage | Tagged: Buck, Devinyl, Front spar, Ginger, Jack, Rear spar, Ribs, Riveting, shoot, skeleton, skin, So is your face, spar, Squeeze | Permalink
Posted by Andrew
After 9 days of not working on the airplane, I finally made it out to the garage. In all fairness, though, I spent all last week working out hard, and preparing for a bachelor party at Snowshoe. West Virginia, right? Yup. It was actually pretty cool there. It was in the midst of the big blizzard that bent the east coast over last week, so Showshoe got somewhere around 20 inches of snow. Legend…wait for it…dary.
Anyway, I had previously drilled out the front spar(VS-702) to tip rib (VS-706) rivets, so here are the replacements. The one on the left doesn’t look all that good, but this is my third try, and I think I am going to leave good enough alone.
Front spar to tip rib rivets. Left one sucks, but I'm not going to make it any worse.
Then, I reset the VS-704 root rib to front spar rivets. I set the middle one fine, then messed up the outer two. Drill out, and reset them just fine on the second try.
Looking good from this side.
Here’s a shot of the shop heads for those three rivets.
Here are the shop heads for those three. Not too bad.
Next, the instructions tell you to cleco on the skin and start riveting. Here’s a shot of me getting ready to rivet.
Start from the middle of the front spar and work outboard, then back to the start and work inboard. Then, rivet along the middle rib aft.
Here’s a shot of some shop heads. You’ll have to click on the picture to see them.
Nice looking shop heads. You can also see my interior skin masking practice. Looks good, doesn't it?
More shop heads.
Another shot of the shop heads for VS-702 front spar and VS-707 middle rib.
And one more…
Once I get the other side of the skin riveted, I can take off the blue vinyl from the inside of the skins.
After riveting one side of the skin, I had to head inside to watch UNC play Dook. (Yes, that is how you spell Dook.)
Starting to look like something that could fly.
One hour today. I drilled out 3 rivets , set 5 rivets on the skeleton and 39 on the left VS skin. 44 total. Booyah.
Leave a Comment » | Empennage | Tagged: Devinyl, Empennage, Front spar, Riveting, skeleton, skin, spar, VS | Permalink
Posted by Andrew
I worked in sections today.
There was a big storm here last night, (and all of today), but I’ve learned that cleaning off the driveway is a lot easier if you do it when it is 3″ two times instead of once after 6″ has accumulated. Here’s what I woke up to this morning.
Snow!
Here’s after about an hour of shoveling. Good workout.
Coming down fast, but at least I cleared off the first 6".
Then, I got the c-frame out and finished the VS skin dimpling. I replaced the blue tape on the male die, and got almost no circles.
Simple but effective dimpling setup.
Then I countersunk all of the lower forward spar reinforcement holes from the plans. I haven’t used the countersink since I had to countersink HS-710 and HS-714 to accept a #30 dimple, so the countersink cage was already set up. All I had to do was verify in a piece of scrap. Yup. It’s perfect.
Beautiful countersinking.
Then, I cleaned and primed one interior side of the vertical skin, then the other. Here’s the first side drying.
Hurry up and wait to dry.
After finishing the second side and letting it dry, I pulled the forward section of vinyl off of the interior side of the skin. During assembly, no bucking bars will be needed in there, so there is no risk of scratching. Then I finished edge finishing the ribs, spars, and rear spar reinforcement, and primed each one. I didn’t prime them sitting perfectly horizontal, so I got some runs and some nastiness; some of them ended up getting touched up, and some got a second coat. After they were all dry, I cleco those bad boys together in preparation for riveting.
Skeleton and rear spar taking shape.
I started with the skeleton, middle rib. Here’s my first VS rivet.
First VS rivet.
Then, I moved to the tip. See the upper rivet? The skins are sitting flush, this will have to be drilled out.
Ahhh! I suck at riveting.
And the lower rivet there started to bend over. I’ll have to drill out both rivets.
Two rivets to be drilled out.
Back to the middle rib, two more perfect rivets.
There are pretty good. I need to make sure that bottom one is driven enough.
See the fourth rivet from the right? Started to bend over, so I’m going to drill it out. Also, I’m going to put the shop heads on the thicker material here, also, they’ll be easier to inspect.
Uh oh. See the third rivet from the right? I was supposed to wait and rivet this with the skeleton. Slow down and follow the directions!
Two more rivets to be drilled out.
But I was feeling good about squeezing, so I kept going. Until these 4 rivets. Terrible…they all started to bend over. I think my rivet squeezer sucks. I have to squeeze really hard and it it tough to keep everything aligned. I think after I drill these out I am going to shoot and buck these.
4 bad rivets to be drilled out.
At this point, I had to walk away, I was tired, frustrated, and not making any progress. Ugh.
So far, 3.5 hours. I set some rivets today, but I’m not going to count any of them until I drill them out. I’ll update the rivet count later.
Leave a Comment » | Empennage | Tagged: C-frame, Dimpling, Front spar, Priming, Rear spar, Ribs, Riveting, Scotchbrite, scuff, skeleton, skin, spar, Vinyl | Permalink
Posted by Andrew
Today, I didn’t make it outside until late, so I didn’t get a lot of work done. Here’s me starting on deburring the skin. Yes, I am using the Van’s recommended “spin a drill bit in your fingers” method. It works for me.
Action shot of me deburring.
An example of a deburred hole. The hole on the right is deburred. There is a very small chamfer on it from the oversized drill bit. It’s easier to see because it’s catching the light from above.
Deburred hole there on the right.
After deburring, I scuffed up the interior of the skin with a maroon scotchbrite pad.
Scuffed, ready to dimple.
Because it was so late, I didn’t want to break out the c-frame. I grabbed the hand squeezer and finished what I could reach.
These are regular (not "tank") dimples. No circles when you use the blue tape trick.
And here’s the vertical stabilizer skin, deburred and dimpled around the perimeter. When sound level permits, I’ll get the c-frame out and dimple the remaining holes.
Almost done with the skin.
I counted 104 holes per side for deburring. That’s 208 holes, 416 deburring operations needed. I usually spin the bit 4 times, which makes 1664 spins of the drill bit. Oww…
1.0 hour closer to being done.
Leave a Comment » | Empennage | Tagged: C-frame, Deburring, Dimpling, Empennage, scuff, skin, Squeeze, VS | Permalink
Posted by Andrew
No pictures tonight.
I broke out the cordless drill (quieter than the air drill) and finished matchdrilling the right side of the vertical stabilizer.
Same routine. Drill every other hole, mark with a dry-erase marker, move clecos, drill remaining holes. Because the root forward rib gave me a little trouble when clecoing during initial assembly, I had 100% clecoed it. For this area, I removed one cleco, matchdrilled, then replaced the cleco. I just didn’t want it to move around on me at all.
Since I forgot to take a picture, here’s another picture of Jack and Ginger.
Ginger all up in your business, Jack in the background.
Half an hour. Not bad for a night I wasn’t planning on working on the airplane.
Leave a Comment » | Empennage | Tagged: drill bit, Empennage, Ginger, Jack, Match-drilling, skeleton, skin, spar, VS | Permalink
Posted by Andrew
First thing after breakfast, I snagged the two VS spars and the spar reinforcement and headed into the kitchen to finish some surface prep. After about an hour, I had all three pieces scuffed up, cleaned, and back outside. Here is a shot during scuffing. You can see the top half has been scotchbrited and the bottom half is the raw part after removing the blue vinyl.
You can even see my hand and the camera in the bottom half.
Here’s the spar reinforcement before finishing.
Rear spar reinforcement.
All three after scuffing. (Along with the ribs from last night.)
Looking good.
Then, I bent the rib flanges to exactly 90 degrees using my new hand seamers, and fluted the ribs.
Fluted, ready for assembly.
I started clecoing the rear spar doubler to the rear spar, and then realized they want you to put the hinge brackets in now. I quickly located VS-410PP, VS-411PP, and VS-412PP, and got the Goo Gone out to help pull these stickers off.
These part number stickers are a pain in the butt to get off cleanly.
While I waited for the Goo Gone to do its magic, I decided to start clecoing the front spar and ribs together. You can also see the rear spar and rear spar reinforcement in the upper left corner of this picture.
Tip rib attached.
Then, I clecoed in the rear spar. Here, you can also see the hinge brackets waiting for the Goo Gone.
Middle rib attached.
Finally, I clecoed in the root ribs (fore and aft).
Root ribs attached.
Then, I cleaned off the hinge brackets, got them clecoed to the rear spar, and clecoed the rear spar to the front spar and ribs.
Looks like an airplane again.
I followed Mike Bullock’s advice and clamped the rear spar to a couple of 2x4s. This let me matchdrill the rear spar vertically, which helps a lot with getting a perfectly straight hole.
Rudimentary VS jig for matcdrilling the rear spar.
Here’s my process. Cleco every other hole, match drill, mark the drilled hole with a dry-erase dot, move the clecos, repeat. Here, you can see my dots.
Dry-erase dots help me know which holes I've drilled.
After finishing up the ones you can reach from the aft side of the rear spar, I flipped the whole assembly over and match-drilled the two remaining holes (that aren’t drilled in the upper half of the lower set of hinge brackets).
12" bit doing its thing...
Next, we get to cleco on the skin, wuhoo!
It looks like another airplane part.
Then, time to matchdrill the skin to the spars and ribs. Same process here. Cleco every other hole, drill, mark dots, move clecos, repeat.
Match-drilling the skin.
Here, you can see that I am in the middle of moving clecos. The one in the center of the picture gets moved one left (into the marked, already drilled hole), then the one to the left of that gets moved one left, and so on.
Example of brand new cleco on the left, and two used clecos in the middle. Eh, they work just fine, they're just not as pretty.
I got the left side of the vertical match-drilled, then flipped it over, took this picture, and then headed inside.
Ready for the second side of match-drilling. Maybe later tonight or tomorrow.
3.0 solid hours today. Good work all around.
Leave a Comment » | Empennage | Tagged: cleco, Empennage, fluting, Front spar, Match-drilling, Rear spar, Ribs, Scotchbrite, scuff, skeleton, skin, spar, VS | Permalink
Posted by Andrew
Andrew's RV-7 Build Log 