Every time I look at the maintenance situation with the cowls on the RV-6, it looks worse. I went out to the hangar tonight and removed the bottom half so I could at least proceed with the oil change. As I was removing it (hard to do alone, even harder when I get a call from work that I have to take while trying not to drop the precariously dangling cowl) I noticed that a whole set of hinge hoops are missing from the left side air inlet. Where'd they go? EllifIknow. But they sure need to be replaced! Luckily, I ordered a six foot length of the hinge material from Van's.
I more or less have a plan for the repair, but it involves fiberglass work. Ugh. I also need to pull out the plans and manual and reverse engineer how the hinges were installed in the first place, the plan being to end up with a repair that is at least as strong as the original installation. Not that the original installation is bathing itself in glory these days.
All of this is going to have to be in lieu of time spent building the RV-12. If one were to anthropomorphize the RV-6 (which I do, I suppose, by assigning him a gender and a name), one might assume that he is acting up in rebellion to the new kid on the block diverting so much of my attention and effort.
Bad Papa! Bad!
Nope, I don't anthropomorphize at all, do I?
Thursday, November 12, 2009
Wednesday, November 11, 2009
Am I on a schedule?
Hugo asked:
Regarding the winter season, as it stands today it's already getting dark too early for me. Experience has taught me that the early darkness of the next three months will sap my strength and initiative if I don't have something to compel me to activity. I'm starting to feel it already. As mentioned on my flying blog, I have a maintenance problem with the other plane in the Schmetterling fleet. Last night I went out to the hangar to take a drastic action - I had to drill out all of the rivets that hold the cowl hinge in place. It was the action of last resort because it will take a lot of work to repair the now enlarge holes in the fiberglass of the cowl, and once that's done I'll still need to buy, fit, and drill a new length of hinge material. Finally, it will need to be painted with paint that I don't have, and matching the color exactly will be a challenge. It took roughly an hour to drill out the rivets and get the cowl off of the airplane. By the time I had that done, it was 6:30 and already dark. Between the depression of having maimed my baby and the early darkness, I didn't have any interest in doing even the most mundane RV-12 work. In other words, I spent the evening in a funk.
Fortunately, that won't last long. I'm already thinking about which things to tackle first and what I can get done on the 12 tonight. Today I'll order the parts I need for the RV-6 from Van's and force myself to just forget about the broken airplane sitting forlornly in its hangar for a few days. Tonight, I will be back to work on the RV-12.
Are you working on any kind of a timeline on your build, or are you just letting your pocketbook dictate the speed of your build?Neither, really. While I eagerly anticipate the completion of the plane because, well, it will be a brand new plane, I view the construction of it as a purely recreational and educational activity. I don't handle the winter months well (more on that in a bit) and desperately need something to keep myself occupied during the dark evenings and inclement weekends that are par for the course from December to March. Even during the rest of the year, I often lack for meaningful projects to keep my hands occupied in off-work hours. Sure, I have a tentative timeline; I think it should be done in two or three years. The problem with setting any firmer schedule than that is that it makes the work feel like, well, work. I get enough of that during the days at the paying job, thanks. I think striving for a sane balance between airplane building and all of the other things that I do (for example, I have four game reviews to write in the next two weeks for GamingNexus.com) will keep the project as enjoyable to me as it has been for this last month.
Regarding the winter season, as it stands today it's already getting dark too early for me. Experience has taught me that the early darkness of the next three months will sap my strength and initiative if I don't have something to compel me to activity. I'm starting to feel it already. As mentioned on my flying blog, I have a maintenance problem with the other plane in the Schmetterling fleet. Last night I went out to the hangar to take a drastic action - I had to drill out all of the rivets that hold the cowl hinge in place. It was the action of last resort because it will take a lot of work to repair the now enlarge holes in the fiberglass of the cowl, and once that's done I'll still need to buy, fit, and drill a new length of hinge material. Finally, it will need to be painted with paint that I don't have, and matching the color exactly will be a challenge. It took roughly an hour to drill out the rivets and get the cowl off of the airplane. By the time I had that done, it was 6:30 and already dark. Between the depression of having maimed my baby and the early darkness, I didn't have any interest in doing even the most mundane RV-12 work. In other words, I spent the evening in a funk.
Fortunately, that won't last long. I'm already thinking about which things to tackle first and what I can get done on the 12 tonight. Today I'll order the parts I need for the RV-6 from Van's and force myself to just forget about the broken airplane sitting forlornly in its hangar for a few days. Tonight, I will be back to work on the RV-12.
Monday, November 9, 2009
Sunday, November 8, 2009
We're starting to see more photos of flying RV-12s
I'm quite happy to have found this one as it shows the area where I'm currently building. You can plainly see the Flettner tab:
Building an airplane: it ain't all sexy
There's a lot of grunt work that comes with building an airplane. For every session pulling rivets with the awesomely powerful and inarguably sexy pneumatic rivet puller, there are hours of menial effort in deburring, fitting, test assembly, test finished de-clecoing, and cleaning up the resultant mess.
Last night I spent a few hours deburring the major components of the stabilator.
This morning, I enjoyed a few hours outside in the glorious Native American (nee Indian) summer we're having. What was I doing out there? Well, finally cutting up the crate of certified insect-free lumber that the tail kit arrived in.
Finally, a chance to use my saws-all! Or, as I like to call it, the bone saw. Because make no mistake, this saw doesn't care whether or not what you put in front of it is wood, metal, skin, or bone. It will saw through it! As an exercise, count how many safety infractions and/or imminent personal disasters you can find in this picture:
Brave Sir Hogarth, true to his ironically given nickname, was keeping a safe (and sane) distance from the events:
He ain't the bravest pup of the litter, but he ain't all that stupid either.
I'm wearing just the right shoes, though. I only buy them for the name:
Miraculously, I still have all my digits! Or, more importantly, I can still count to 20 if I need to:
Using the same level of foresight that has gotten me where I am today, I have the wood all loaded up to haul off to.... well, I have no idea at all where I'm going to haul it off to. That's TBD.
For the rest of the day the plan is to fly the RV-6 a little bit, if only to get the oil warm enough to drain out for the last oil change of the year.
Last night I spent a few hours deburring the major components of the stabilator.
This morning, I enjoyed a few hours outside in the glorious Native American (nee Indian) summer we're having. What was I doing out there? Well, finally cutting up the crate of certified insect-free lumber that the tail kit arrived in.
Finally, a chance to use my saws-all! Or, as I like to call it, the bone saw. Because make no mistake, this saw doesn't care whether or not what you put in front of it is wood, metal, skin, or bone. It will saw through it! As an exercise, count how many safety infractions and/or imminent personal disasters you can find in this picture:
Brave Sir Hogarth, true to his ironically given nickname, was keeping a safe (and sane) distance from the events:
He ain't the bravest pup of the litter, but he ain't all that stupid either.
I'm wearing just the right shoes, though. I only buy them for the name:
Miraculously, I still have all my digits! Or, more importantly, I can still count to 20 if I need to:
Using the same level of foresight that has gotten me where I am today, I have the wood all loaded up to haul off to.... well, I have no idea at all where I'm going to haul it off to. That's TBD.
For the rest of the day the plan is to fly the RV-6 a little bit, if only to get the oil warm enough to drain out for the last oil change of the year.
Saturday, November 7, 2009
After the Flettner Tab? An unscheduled break.
I re-riveted the control horn on the left side of the Flettner tab and now the two halves fit together like two slices of Oscar Mayer 98% Fat Free Sliced Beef Bologna, if you'll forgive the uncompensated product placement simile. Times are tough (but Oscar Mayer 98% Fat Free Sliced Beef Bologna isn't!) and Schmetterling is always on the watch for new revenue stream opportunities! Here's hoping that the wonderful and caring marketing folks at Oscar Mayer see the enormous opportunities here.
I'm glad (and yes, somewhat proud of myself) for going back and fixing the left side. Even if it had fit on the airplane, it would have been one of those things that, once I was aware of it, would always catch my eye and act as an eternal badge of shame. But now? I'm thrilled with how nice it looks:
Allow me, if you will, to segue onto another subject. I discovered the flaw in the control horn attachment because I was able to leverage our modern internet-based communication opportunities to learn from others that have built before me. Had I not been researching ahead by reading other build logs, I would not have known to be hyper critical about the spacing of that control horn. In the grand scheme, this was a minor fix to a minor problem. But as I was reading ahead and preparing to start on section 9 (the horizontal stabilator), I came across a much more serious issue that I would have gotten wrong, and this one would have cost some me some money. Money unlikely to be recouped from my as yet to be realized revenue from the good folks at Oscar Mayer.
The first step in the building of the HS is a load of countersinking. Nothing new there, right? Here's the excerpt from the plans:
Note "MACHINE CSK, CS4-4" and "MACHINE CSK, AN426AD3" and tell be what you'd do. Well, you'd have done what I would have done, which is to grab your countersink bits and countersunk the holes. You simultaneously would have ruined both of your HS-1211 spars. Why? Good question! You would have ruined those parts because the CS4-4 rivets require a 120 degree countersink, not the standard 100 degree countersink. Somewhere (but not in the plans, as far as I can tell) there will be a small-font, completely obscure chart that tells you this. I contend that a far better approach, particularly in the case of the anyone-can-build-it RV-12, would have been to spend the $.000001 in toner required to print "WITH 120 DEGREE CS BIT" on the page.
I included the rivets in the picture so you can see the difference in the angles. It's very, very subtle. If Van's is counting on builders like myself noticing that kind of disparity and wondering if perhaps, just maybe, we might need a different countersink bit, well, I don't see it happening.
So, disaster was narrowly averted, but now I have to wait until the 120 bit arrives via FedEx Geriatric Turtle non-express (why am I so cheap on the shipping? Hey, ask Oscar Mayer!) some time next week. As long as I was getting hooked for $7.95 shipping on a tool that weighs less than an ounce, I went ahead and ordered another specialty tool that my newfound practice of reading ahead indicates I will need within a couple of weeks.
For now I will get the Flettner pieces final riveted and look ahead in the HS plans to see what needs to be deburred and/or fluted. The HS is a pretty big chunk O' airplane, so there's bound to be at least three or four days worth of that kind of stuff.
I'm glad (and yes, somewhat proud of myself) for going back and fixing the left side. Even if it had fit on the airplane, it would have been one of those things that, once I was aware of it, would always catch my eye and act as an eternal badge of shame. But now? I'm thrilled with how nice it looks:
Allow me, if you will, to segue onto another subject. I discovered the flaw in the control horn attachment because I was able to leverage our modern internet-based communication opportunities to learn from others that have built before me. Had I not been researching ahead by reading other build logs, I would not have known to be hyper critical about the spacing of that control horn. In the grand scheme, this was a minor fix to a minor problem. But as I was reading ahead and preparing to start on section 9 (the horizontal stabilator), I came across a much more serious issue that I would have gotten wrong, and this one would have cost some me some money. Money unlikely to be recouped from my as yet to be realized revenue from the good folks at Oscar Mayer.
The first step in the building of the HS is a load of countersinking. Nothing new there, right? Here's the excerpt from the plans:
Note "MACHINE CSK, CS4-4" and "MACHINE CSK, AN426AD3" and tell be what you'd do. Well, you'd have done what I would have done, which is to grab your countersink bits and countersunk the holes. You simultaneously would have ruined both of your HS-1211 spars. Why? Good question! You would have ruined those parts because the CS4-4 rivets require a 120 degree countersink, not the standard 100 degree countersink. Somewhere (but not in the plans, as far as I can tell) there will be a small-font, completely obscure chart that tells you this. I contend that a far better approach, particularly in the case of the anyone-can-build-it RV-12, would have been to spend the $.000001 in toner required to print "WITH 120 DEGREE CS BIT" on the page.
I included the rivets in the picture so you can see the difference in the angles. It's very, very subtle. If Van's is counting on builders like myself noticing that kind of disparity and wondering if perhaps, just maybe, we might need a different countersink bit, well, I don't see it happening.
So, disaster was narrowly averted, but now I have to wait until the 120 bit arrives via FedEx Geriatric Turtle non-express (why am I so cheap on the shipping? Hey, ask Oscar Mayer!) some time next week. As long as I was getting hooked for $7.95 shipping on a tool that weighs less than an ounce, I went ahead and ordered another specialty tool that my newfound practice of reading ahead indicates I will need within a couple of weeks.
For now I will get the Flettner pieces final riveted and look ahead in the HS plans to see what needs to be deburred and/or fluted. The HS is a pretty big chunk O' airplane, so there's bound to be at least three or four days worth of that kind of stuff.
Friday, November 6, 2009
Late night Mulligan on left Flettner
Poor Anton Flettner must be doing pirouettes in his coffin over my ham-handed building of his eponymous anti-servo tabs. Last night, after buttoning them up for the final riveting scheduled for tonight, I was perusing a builder's log on the web and found that the guy had run into a problem when trying to install the tabs onto the stabilator. The problem was that the fit where they meet is very tight and he had gotten a gap between the control horn and the rib when he riveted them together. I thought that it might be a good idea to head back down to the shop and inspect mine.
What I found was that the right side was tight and flush with the edge of the skin, but the left side had enough of a gap that it was slightly outside of the edge of the skin. Rather than wait to find out whether it was going to cause a problem later after everything was all riveted shut, I decided to drill out the five rivets and re-do it while it was still easily accessible. Drilling the rivets out was easy-peasy, now that I've had a bit of practice at it, but when I clecoed the control horn back into place I saw that there were a couple of problems. One was the issue that caused the gap to form in the first place, while the second was caused due to the riveting problem.
The first was that the edge of the skin was not quite flush with the outside of the rib. This caused the control horn to not sit flat against the side of the rib. When I squeezed the rivet, this gap allowed the rivet to fatten up just a little bit between the two surfaces. That fat part of rivet in the gap caused the second problem: the hole in the rib got a reverse dimple in it. In other words, it was now an outie, not an inney. That prevented the horn from sitting flush against the rib and virtually guaranteed that I'd get the same result if I just tried to rivet the part back in place without some form of corrective action.
The first thing to do was to file down the skin to that it was flush with the rib. That didn't take much filing at all - it was a very small overhang, but just enough to cause the potential fitting problem. The second was to fix the outie. I did that by putting a very slight dimple in it with the dimple/die set that I used to dimple the holes in the vertical stab front fairing.
The control horn is now clecoed back into place and sitting tight against the rib - no more gap. I'll rivet it tonight just before going to the hangar for the final skin riveting.
What I found was that the right side was tight and flush with the edge of the skin, but the left side had enough of a gap that it was slightly outside of the edge of the skin. Rather than wait to find out whether it was going to cause a problem later after everything was all riveted shut, I decided to drill out the five rivets and re-do it while it was still easily accessible. Drilling the rivets out was easy-peasy, now that I've had a bit of practice at it, but when I clecoed the control horn back into place I saw that there were a couple of problems. One was the issue that caused the gap to form in the first place, while the second was caused due to the riveting problem.
The first was that the edge of the skin was not quite flush with the outside of the rib. This caused the control horn to not sit flat against the side of the rib. When I squeezed the rivet, this gap allowed the rivet to fatten up just a little bit between the two surfaces. That fat part of rivet in the gap caused the second problem: the hole in the rib got a reverse dimple in it. In other words, it was now an outie, not an inney. That prevented the horn from sitting flush against the rib and virtually guaranteed that I'd get the same result if I just tried to rivet the part back in place without some form of corrective action.
The first thing to do was to file down the skin to that it was flush with the rib. That didn't take much filing at all - it was a very small overhang, but just enough to cause the potential fitting problem. The second was to fix the outie. I did that by putting a very slight dimple in it with the dimple/die set that I used to dimple the holes in the vertical stab front fairing.
The control horn is now clecoed back into place and sitting tight against the rib - no more gap. I'll rivet it tonight just before going to the hangar for the final skin riveting.
Thursday, November 5, 2009
Almost done with the Flettners
I had a long-ish day at work today and by the time I fought my way across town through rush hour traffic, relaxed for a half hour while the Co-owner prepared dinner, and wolfed down my share (and a little more) of same, there wasn't much time or energy left for a long session on the Schmetterling production floor.
Perhaps my mental fatigue had carried over from work. How bad was it at work? Well, I commented a piece of programming code thusly:
// I'd be disappointed and more than a little perplexed if this ever happened
Someday my replacement will look at that with the same level of confusion and WhatDaHellism that I looked at this tonight:
Follow me as I try to do the math:
"Remove the hinge pin from one AN257-P3X6'"
Ok, after having done so I have two pieces of AN257-P3X6', right?
Then there's some blah blah blah, followed by an all-caps (that must means it's important!) "MAKE FOUR HINGE HALVES"
Huh? Out of what, exactly? The two pieces I have now?? Am I supposed to cut them each in half? Well, no. I'm supposed to trim them to 32 1/2 inches. I gave up and figured I'd worry about the other two hinge halves later. I won't need them until section 11. In the meantime, the tin snips cut the two halves off at the 32 1/2 inch mark quite easily:
The second half of the page provided detailed instructions and drawings regarding the use of the HS-1223 drill guide. What it didn't provide was any hint at all regrading where to find the HS-1223 drill guide. After a prolonged search, I found it in one of the little bags. That was after finally resorting to pulling out the inventory sheets and looking at them a half dozen times before finding the location of the HS-1223 drill guide at the very bottom of the last page.
The HS-1223 drill guide is supposed to fit between the hoops of the hinge and get clamped into place. Unfortunately, it's a very tight fit. So tight, in fact, that trying to push it into place bent of the hoops on the hinge, a sin that I will pay dearly for in section 11. I finally threw caution to the wind and filed off a nanometer of one of the edges of the HS-1223 drill guide. Things went swimmingly after that:
The HS-1223 dill guide had to be unclamped and moved to the next area of the tab for drilling. It took awhile. The second tab went much faster and easier, primarily because I knew exactly where the HS-1223 drill guide was.
Both parts are clecoed up and ready for transport up to the hangar for riveting, a job that I have (wisely, in my opinion) decided to defer until tomorrow night.
Perhaps my mental fatigue had carried over from work. How bad was it at work? Well, I commented a piece of programming code thusly:
// I'd be disappointed and more than a little perplexed if this ever happened
Someday my replacement will look at that with the same level of confusion and WhatDaHellism that I looked at this tonight:
Follow me as I try to do the math:
"Remove the hinge pin from one AN257-P3X6'"
Ok, after having done so I have two pieces of AN257-P3X6', right?
Then there's some blah blah blah, followed by an all-caps (that must means it's important!) "MAKE FOUR HINGE HALVES"
Huh? Out of what, exactly? The two pieces I have now?? Am I supposed to cut them each in half? Well, no. I'm supposed to trim them to 32 1/2 inches. I gave up and figured I'd worry about the other two hinge halves later. I won't need them until section 11. In the meantime, the tin snips cut the two halves off at the 32 1/2 inch mark quite easily:
The second half of the page provided detailed instructions and drawings regarding the use of the HS-1223 drill guide. What it didn't provide was any hint at all regrading where to find the HS-1223 drill guide. After a prolonged search, I found it in one of the little bags. That was after finally resorting to pulling out the inventory sheets and looking at them a half dozen times before finding the location of the HS-1223 drill guide at the very bottom of the last page.
The HS-1223 drill guide is supposed to fit between the hoops of the hinge and get clamped into place. Unfortunately, it's a very tight fit. So tight, in fact, that trying to push it into place bent of the hoops on the hinge, a sin that I will pay dearly for in section 11. I finally threw caution to the wind and filed off a nanometer of one of the edges of the HS-1223 drill guide. Things went swimmingly after that:
The HS-1223 dill guide had to be unclamped and moved to the next area of the tab for drilling. It took awhile. The second tab went much faster and easier, primarily because I knew exactly where the HS-1223 drill guide was.
Both parts are clecoed up and ready for transport up to the hangar for riveting, a job that I have (wisely, in my opinion) decided to defer until tomorrow night.
Wednesday, November 4, 2009
More Flettner work: yet one more job saved or created
After gracing my family with my cheerful, gregarious presence for the last one and a half evenings, it was back to work on the Flettner tab tonight. Having resolved the mystery of the too-small holes in the rib flanges to my satisfaction, I went ahead and drilled them out with the #30 to make them big enough to take a blind rivet. Having done that, they all had to be removed for deburring.
Deburring the inside of the tiny little rib flanges can't be done with the normal power-driven deburr bit. Rather, I have to use this tool:
I don't like the looks of it. It looks too much like a dental tool or an instrument of torture. Granted, the distinction between the two is almost vanishingly subtle. With this tool, though, I can reach through the top of the hole and deburr the other side.
At this point, Van's says to rivet the top of the skin to the top of the ribs. If you read ahead, the step after that has you riveting in the control horn. Some folks on the Vans Air Force site said that it might be easier to rivet the control horn in place and then rivet down the top skin. I clecoed everything together and practiced both methods and found that the Van's method worked best for me. Differences of technique such as this with different builders more often than not come down to slight differences in the tools being used. With the rivet squeezer and rivet pullers that I have, the Van's method provided easier access, although I did end up bending one of the rib flanges. That was easy to bend back into shape, though. I went ahead and riveted the top skin to the ribs:
Here's the "raw" control horn:
It gets riveted in with solid flush rivets, so it needs to be countersunk:
There's nothing prettier than a countersunk hole, in my opinion. The machined look of it just makes it look more sophisticated somehow.
Here it is clecoed into place:
And here I am reaching back inside there to squeeze the rivets:
All done:
Your eyes didn't deceive you in the pictures if you noticed that one of the pictures shows a control horn labeled 'L' and one laebled 'R': there are two tabs, actually, a left and a right.
Here they are in their relative positions as they will be installed on the airplane:
Tomorrow night I will fabricate and rivet on the hinge strip that will attach the Flettner tabs to the horizontal stabilator. After that it's a simple matter of riveting the bottom skin to the ribs.
Deburring the inside of the tiny little rib flanges can't be done with the normal power-driven deburr bit. Rather, I have to use this tool:
I don't like the looks of it. It looks too much like a dental tool or an instrument of torture. Granted, the distinction between the two is almost vanishingly subtle. With this tool, though, I can reach through the top of the hole and deburr the other side.
At this point, Van's says to rivet the top of the skin to the top of the ribs. If you read ahead, the step after that has you riveting in the control horn. Some folks on the Vans Air Force site said that it might be easier to rivet the control horn in place and then rivet down the top skin. I clecoed everything together and practiced both methods and found that the Van's method worked best for me. Differences of technique such as this with different builders more often than not come down to slight differences in the tools being used. With the rivet squeezer and rivet pullers that I have, the Van's method provided easier access, although I did end up bending one of the rib flanges. That was easy to bend back into shape, though. I went ahead and riveted the top skin to the ribs:
Here's the "raw" control horn:
It gets riveted in with solid flush rivets, so it needs to be countersunk:
There's nothing prettier than a countersunk hole, in my opinion. The machined look of it just makes it look more sophisticated somehow.
Here it is clecoed into place:
And here I am reaching back inside there to squeeze the rivets:
All done:
Your eyes didn't deceive you in the pictures if you noticed that one of the pictures shows a control horn labeled 'L' and one laebled 'R': there are two tabs, actually, a left and a right.
Here they are in their relative positions as they will be installed on the airplane:
Tomorrow night I will fabricate and rivet on the hinge strip that will attach the Flettner tabs to the horizontal stabilator. After that it's a simple matter of riveting the bottom skin to the ribs.
Monday, November 2, 2009
First blood! Flettner tab 1, me 0
I started on the anti-servo tab tonight. I promised to explain what an anti-servo tab is/does in the last posting, but I'm too tired to write it up. Wikipedia has a nice, concise explanation of it here.
Too lazy to click through? Well, ok. It's just as easy for me to copy and paste, but you'll miss out on the explanatory diagram:
Simply for the pleasure of exercising my pomposity and fluffing up my street cred, I will hereafter refer to it as the Flettner tab.
The Flettner tab looked like it would be a one evening wonder, going from deburring to completion in a single work session. 'Twas not to be. There's nothing truly exotic about the construction of the Flettner tab (getting tired of that yet?) other than its size: it's the smallest thing I've worked on yet. You wouldn't think that would have any adverse effect on the difficulty, but it does. It makes it harder to deburr. Well, it was easy enough on the outside, but none of my fancy powered deburring tools would fit down inside. Ugh, deburring with hand tools! How utterly quaint! Naught to be done about it, though, as the deburring must be done.
Here's a nifty little tool that has various bits that can be installed for different deburring situations. This bit is used for edges:
You just position it to get the sharp edge of the tool right where it can do the most good and stroke it down the length of the edge:
What you don't want to do, though, is slip and run your thumb along the edge yet to be duburred:
Ouch! Sure points out why we deburr, doesn't it?
After getting a bandaid, the next step is to cleco the little bitty even-harder-to-deburr ribs into place. Should be easy, but Van's threw a little wrinkle at me:
See how the hole closest to the trailing edge is smaller than the rest? Do you wonder why? Well, so do I. Either through loss of blood or the fatigue of a brain-draining Monday at my paying job, I just didn't feel like trying to figure it out. It'll still be there tomorrow. For tonight, here's how far I got before quitting time:
Here's a thought I came up with later:
Too lazy to click through? Well, ok. It's just as easy for me to copy and paste, but you'll miss out on the explanatory diagram:
A Servo tab (sometimes called a Flettner tab after its inventor Anton Flettner) is a small hinged device installed on an aircraft control surface to assist the movement of the control surface.
Servo tabs
Servo tabs move in the opposite direction of the control surface. The tab has a leverage advantage, being located closer to the trailing edge of the surface and thus can lever the control surface in the opposite direction. This has the effect of reducing the control force required by the pilot to move the controls.
In the case of some aircraft the servo tab is the only control that is connected to the pilot's stick or wheel. The pilot moves the wheel which moves the servo tab and then the servo tab, using its mechanical advantage, moves the elevator or aileron, which is otherwise free-floating.
Anti-servo tabs
An anti-servo tab works in the opposite way to a servo tab. It deploys in the same direction as the control surface, making the movement of the control surface more difficult and requires more force applied to the controls by the pilot. This may seem counter-productive, but it is commonly used on aircraft where the controls are too light or the aircraft requires additional stability in that axis of movement. The anti-servo tab serves to artificially increase stability and also make the controls heavier in feel to the pilot.
On some aircraft with all-flying stabilators (ed: like the RV-12) an anti-servo tab acts as a trimming device. In this use some manufacturers term it a "balance tab" or "anti-balance tab".
Simply for the pleasure of exercising my pomposity and fluffing up my street cred, I will hereafter refer to it as the Flettner tab.
The Flettner tab looked like it would be a one evening wonder, going from deburring to completion in a single work session. 'Twas not to be. There's nothing truly exotic about the construction of the Flettner tab (getting tired of that yet?) other than its size: it's the smallest thing I've worked on yet. You wouldn't think that would have any adverse effect on the difficulty, but it does. It makes it harder to deburr. Well, it was easy enough on the outside, but none of my fancy powered deburring tools would fit down inside. Ugh, deburring with hand tools! How utterly quaint! Naught to be done about it, though, as the deburring must be done.
Here's a nifty little tool that has various bits that can be installed for different deburring situations. This bit is used for edges:
You just position it to get the sharp edge of the tool right where it can do the most good and stroke it down the length of the edge:
What you don't want to do, though, is slip and run your thumb along the edge yet to be duburred:
Ouch! Sure points out why we deburr, doesn't it?
After getting a bandaid, the next step is to cleco the little bitty even-harder-to-deburr ribs into place. Should be easy, but Van's threw a little wrinkle at me:
See how the hole closest to the trailing edge is smaller than the rest? Do you wonder why? Well, so do I. Either through loss of blood or the fatigue of a brain-draining Monday at my paying job, I just didn't feel like trying to figure it out. It'll still be there tomorrow. For tonight, here's how far I got before quitting time:
Here's a thought I came up with later:
I think the holes in the skins are offset so the top skin will use a different hole in the rib than the bottom. In other words, the top skin will use the furthest aft hole, while the bottom skin will use the second furthest aft. That will keep the rivets from interfering with each other.
As far as having to drill them to #30 when the other holes already have that done, the holes are smaller because if both were large enough for the rivet, (i.e. #30) they'd be giving up a lot of strength since the distance between two #30 sized holes would be much smaller.
Sunday, November 1, 2009
Schmetterling CEO Visit
As a major milestone approaches with the imminent completion of a major aerodynamic surface and flight control, it seemed that it might be a good time for the CEO of our parent company to come for a visit to the production facility. VIP treatment is standard for situations such as these so I took the company plane out to pick him up.
Or, put another way, the weather was gorgeous today and was almost irresistibly beckoning me, but the RV-12 rudder is on the cusp of completion and I really wanted to spend some time doing that. But... there's just no denying the call of a sky that appears as if it may have once or twice heard whispered rumors of these new fangled things called 'clouds' but was believing none of that wild gossip, thank you very much. And calm winds in the forecast as well! Astounding! What better way to kill two birds with one stone (hmm, this seems like a wildly inappropriate time to use that expression) than to fly out to KVES and pick up my Dad and fly him back to Columbus for a shop visit. Sure, it would mean flying him back home as well, but seriously, isn't that really just another cherry on the sundae?
It was a relaxed morning what with the DST 'found' hour to buffer the time between having a hot cup or two of Vitamin P infused coffee and having to head to the airport for departure. There's no lav in an RV-6, remember? Timing is critical. It pays to have some time between bottle and throttle when it comes to flying after a morning of drinking coffee.
The extra hour came from Daylight Savings Time ending later in the year than ever before because our Congress, always eager to flaunt their dominance over us, legislated a seemingly random change in when we shift time. They meddle in so many things anymore that I think a House bill to coerce water into flowing up hill is expected to get voted out of committee next week.
In any event, no one bothered to tell my Garmin 396 of the change of schedule. Try as it might, it just could not find any satellites, my theory being that it was looking at points in space that wouldn't be inhabited by GPS satellites for another hour. Or spots from which satellites had already departed an hour earlier. It could be either - I'm not very good at temporal calculations. If I had to bet, I'd say it was the latter case.
Whatever the cause, buggered if I was going to sit around waiting three months for the clocks to get set back ahead. I'd go without it - I have a nice spare built right into the panel. Although I rarely use it, I do dial in Direct To now and then just to remind myself how. That came in handy today since it was super simple to just dial in KVES and get things going. It's a little less pleasant than the Garmin to use, though:
Always the forgive and forget type, I gave the Garmin another chance. And another, and another, and another. I diddled around with menu pages trying to find a place where I could set the time and, for that matter, the date. It was convinced that it was October 28th. Brilliant little box, but sometimes easily confused. I couldn't find anything that would let me give the unit a temporal foothold on reality, but I did find a way to turn off Daylight Savings Time. I was optimistic about that, but the Garmin stubbornly continued to play the fool:
Finally I stumbled upon a 'Set Location' menu item. Just what I was looking for! You just pick a spot on the map or type in an airport identifier and Bob's your uncle. Well, not so fast: it seems that rather than give it a location as you're pounding through the air at a blistering 3,139 inches per second, you have to be sitting still. I typed in a couple of airports as I flew over or by them, but no luck. As soon as I stopped at KVES, POW!, it found all the satellites it could ever want.
That solved, I got the CEO settled into the right seat and we were off on the trip back to Columbus. The whole VIP treatment thing kind of went sour, though, since I had forgotten to bring the passenger headset. He had to endure the full, unadulterated cacophony of Papa at full gallop. At first I tried cruising at a sedate 2,000 rpm to keep the noise down, but I quickly got bored with that and poured on the coal. After a fuel stop at MadCo, we landed at Bolton and hangared Papa. It was time to visit the shop.
I had the rudder pretty much ready to go for final assembly. Just to provide a complete picture of the work involved, I hadn't deburred the rudder skin yet. A few passes along the ScothBrite wheel made short work of dressing up the edges of the skin and the deburring of the rivet holes is never all that time consuming. It wasn't long at all before we were ready to take the rudder back to the hangar for riveting.
With the construction of the tail kit being well ahead of schedule and the lead time for the next kit (the fuselage) now hovering at somewhere around two months, and in consideration of the all too likely end of year price increase, the discussion turned to whether the order for the fuse kit should be placed and when. The timing of the tail is looking like I will be ready to assemble the too-big-for-the-shop tail cone by the end of December, just in time for the most inhospitable months of the year for working in the hangar. With the fuse kit on site, I could defer the building of the tail cone until Spring and concentrate on the first stages of the fuselage. Right up until the roll bars go on, the fuse is small enough to assemble in the shop.
As with CEOs everywhere in Corporate America, he needed time to think about the proposed schedule changes and their budgetary impact. Deep in thought:
My only fear is that the vertical stab and rudder might be lulling me into over confidence. Maybe the horizontal stab is when this stuff really starts getting hard. I have to say, though, that the RV-12 so far has to be the simplest to build airplane in the world. Seriously, look at this:
The fronts of the rudder skin were already rounded into shape and fit right together with no trouble at all. The skin slid right onto the skeleton and the holes lined up with unconscionable ease. I don't think you can build an RV-9 rudder in just a handful of hours, can you? This thing is amazingly well designed.
We hauled the rudder out to the hangar and pulled about 3/4s of the rivets before we started getting pretty hungry. Also, with the loss of an hour of daylight I had to keep a tight look on the time to make sure I could be back to base before dark. We decided that we'd get started back towards KVES with a lunch stop at Urbana. I always seem to end up at Urbana when it comes to fly-in food...
Hey, you know how you always want to impress your Dad? Well, I got a little help with that today from a couple of total strangers.
"See the kind of people that have planes at Bolton? The kind that drive Porsche and Rolls Royce:"
"I just drive a Subaru because I find spectacularly conspicuous consumption like that somehow demeaning."
Yeah, that's the ticket.
After lunch, I had him stand next to his artwork (he drew the nose art) for a picture:
The flight from Urbana to KVES went fine, although I wouldn't say it was my best landing of the day. The best was a greaser at Urbana. The rest were so-so. The winds were a bit shifty and three out of the six landings were made with light quartering tailwinds. I'm not saying that's what caused the bad ones, but it could be.
The Sun was getting pretty close to the horizon as I flew back towards home, providing perfect lighting to capture a late Fall tapestry:
Bolton tower had been using runway 4 for most of the day but as I was approaching I heard the tower clear a couple of departures to go out on 22 since they were heading southwest. That meant that I had to land on 22 also, and that meant another landing with a slight tailwind. And, it sucked. I sailed right on past taxiway Alpha 3 and couldn't make the turn off until Alpha 4. That's not a big deal as there was another half a mile of runway after Alpha 4, but it's still a bit below my usual standard. Eh, it happens.
Once back I finished up the remaining riveting and headed home with a completed rudder:
Next comes the anti-servo tab. I'll 'splain just exactly what that is next time.
Or, put another way, the weather was gorgeous today and was almost irresistibly beckoning me, but the RV-12 rudder is on the cusp of completion and I really wanted to spend some time doing that. But... there's just no denying the call of a sky that appears as if it may have once or twice heard whispered rumors of these new fangled things called 'clouds' but was believing none of that wild gossip, thank you very much. And calm winds in the forecast as well! Astounding! What better way to kill two birds with one stone (hmm, this seems like a wildly inappropriate time to use that expression) than to fly out to KVES and pick up my Dad and fly him back to Columbus for a shop visit. Sure, it would mean flying him back home as well, but seriously, isn't that really just another cherry on the sundae?
It was a relaxed morning what with the DST 'found' hour to buffer the time between having a hot cup or two of Vitamin P infused coffee and having to head to the airport for departure. There's no lav in an RV-6, remember? Timing is critical. It pays to have some time between bottle and throttle when it comes to flying after a morning of drinking coffee.
The extra hour came from Daylight Savings Time ending later in the year than ever before because our Congress, always eager to flaunt their dominance over us, legislated a seemingly random change in when we shift time. They meddle in so many things anymore that I think a House bill to coerce water into flowing up hill is expected to get voted out of committee next week.
In any event, no one bothered to tell my Garmin 396 of the change of schedule. Try as it might, it just could not find any satellites, my theory being that it was looking at points in space that wouldn't be inhabited by GPS satellites for another hour. Or spots from which satellites had already departed an hour earlier. It could be either - I'm not very good at temporal calculations. If I had to bet, I'd say it was the latter case.
Whatever the cause, buggered if I was going to sit around waiting three months for the clocks to get set back ahead. I'd go without it - I have a nice spare built right into the panel. Although I rarely use it, I do dial in Direct To now and then just to remind myself how. That came in handy today since it was super simple to just dial in KVES and get things going. It's a little less pleasant than the Garmin to use, though:
Always the forgive and forget type, I gave the Garmin another chance. And another, and another, and another. I diddled around with menu pages trying to find a place where I could set the time and, for that matter, the date. It was convinced that it was October 28th. Brilliant little box, but sometimes easily confused. I couldn't find anything that would let me give the unit a temporal foothold on reality, but I did find a way to turn off Daylight Savings Time. I was optimistic about that, but the Garmin stubbornly continued to play the fool:
Finally I stumbled upon a 'Set Location' menu item. Just what I was looking for! You just pick a spot on the map or type in an airport identifier and Bob's your uncle. Well, not so fast: it seems that rather than give it a location as you're pounding through the air at a blistering 3,139 inches per second, you have to be sitting still. I typed in a couple of airports as I flew over or by them, but no luck. As soon as I stopped at KVES, POW!, it found all the satellites it could ever want.
That solved, I got the CEO settled into the right seat and we were off on the trip back to Columbus. The whole VIP treatment thing kind of went sour, though, since I had forgotten to bring the passenger headset. He had to endure the full, unadulterated cacophony of Papa at full gallop. At first I tried cruising at a sedate 2,000 rpm to keep the noise down, but I quickly got bored with that and poured on the coal. After a fuel stop at MadCo, we landed at Bolton and hangared Papa. It was time to visit the shop.
I had the rudder pretty much ready to go for final assembly. Just to provide a complete picture of the work involved, I hadn't deburred the rudder skin yet. A few passes along the ScothBrite wheel made short work of dressing up the edges of the skin and the deburring of the rivet holes is never all that time consuming. It wasn't long at all before we were ready to take the rudder back to the hangar for riveting.
With the construction of the tail kit being well ahead of schedule and the lead time for the next kit (the fuselage) now hovering at somewhere around two months, and in consideration of the all too likely end of year price increase, the discussion turned to whether the order for the fuse kit should be placed and when. The timing of the tail is looking like I will be ready to assemble the too-big-for-the-shop tail cone by the end of December, just in time for the most inhospitable months of the year for working in the hangar. With the fuse kit on site, I could defer the building of the tail cone until Spring and concentrate on the first stages of the fuselage. Right up until the roll bars go on, the fuse is small enough to assemble in the shop.
As with CEOs everywhere in Corporate America, he needed time to think about the proposed schedule changes and their budgetary impact. Deep in thought:
My only fear is that the vertical stab and rudder might be lulling me into over confidence. Maybe the horizontal stab is when this stuff really starts getting hard. I have to say, though, that the RV-12 so far has to be the simplest to build airplane in the world. Seriously, look at this:
The fronts of the rudder skin were already rounded into shape and fit right together with no trouble at all. The skin slid right onto the skeleton and the holes lined up with unconscionable ease. I don't think you can build an RV-9 rudder in just a handful of hours, can you? This thing is amazingly well designed.
We hauled the rudder out to the hangar and pulled about 3/4s of the rivets before we started getting pretty hungry. Also, with the loss of an hour of daylight I had to keep a tight look on the time to make sure I could be back to base before dark. We decided that we'd get started back towards KVES with a lunch stop at Urbana. I always seem to end up at Urbana when it comes to fly-in food...
Hey, you know how you always want to impress your Dad? Well, I got a little help with that today from a couple of total strangers.
"See the kind of people that have planes at Bolton? The kind that drive Porsche and Rolls Royce:"
"I just drive a Subaru because I find spectacularly conspicuous consumption like that somehow demeaning."
Yeah, that's the ticket.
After lunch, I had him stand next to his artwork (he drew the nose art) for a picture:
The flight from Urbana to KVES went fine, although I wouldn't say it was my best landing of the day. The best was a greaser at Urbana. The rest were so-so. The winds were a bit shifty and three out of the six landings were made with light quartering tailwinds. I'm not saying that's what caused the bad ones, but it could be.
The Sun was getting pretty close to the horizon as I flew back towards home, providing perfect lighting to capture a late Fall tapestry:
Bolton tower had been using runway 4 for most of the day but as I was approaching I heard the tower clear a couple of departures to go out on 22 since they were heading southwest. That meant that I had to land on 22 also, and that meant another landing with a slight tailwind. And, it sucked. I sailed right on past taxiway Alpha 3 and couldn't make the turn off until Alpha 4. That's not a big deal as there was another half a mile of runway after Alpha 4, but it's still a bit below my usual standard. Eh, it happens.
Once back I finished up the remaining riveting and headed home with a completed rudder:
Next comes the anti-servo tab. I'll 'splain just exactly what that is next time.
Saturday, October 31, 2009
Riveting battle won, the war proceeds apace
A comment from Wingman Ted on the topic of the ever-bending rivets stated the following:
This is true, and I remember it from the sheetmetal class that I took at the local A&P school. But.... how could the rivet be too long when the rivet gauge borrowed from Co-pilot Rick indicated that the rivet was, if anything, too short? Sure, Van's warns us in section 5 of the manual that there will be cases where a too long rivet is called out in the plans and may need to be shortened, but... the rivet gauge! How could it be wrong??
Well, as it turns out, thusly:
Used that way, the rivet appears much too short. This is a sample photo taken later with a different size rivet and different thickness of metal, though - with the rivet in question, the error was not nearly as obvious. That said, here's how the gauge is supposed to be used:
Makes all the difference!! I didn't find that out until later, though. Still working under the impression that the rivet was bending because I couldn't get the squeezer situated correctly due to interference from the flange, I hauled everything up to the hangar and pulled out my Gucci rivet gun:
Would you guess that it hasn't seen much use in the last couple of years? Yep, both the rivet gun and me were pretty rusty - I drove a couple of practice rivets in a piece of scrap to remind myself how to do it. Then I aligned everything on the problem rivet, gave it a few shots with the rivet gun, and.....
bent it.
Drat. Having exhausted my limited knowledge without any commensurate gain, I contacted Co-pilot Rick for assistance. I loaded everything back into the car and hauled it up to his shop where he tried to drive a straight rivet. It bent. "Ah," he said, " it's too long."
"Impossible," I replied, "I checked it with the gauge."
You can guess how it went from there.
We used the bench grinder to shave a little length off of one of the rivets and Rick was able to drive it in perfectly straight. Only to find a completely new problem: a gap was created between the rib and the spar. That poor little rib by then had something like the fifth rivet drilled out of it. The newest problem was caused by trying to form the shop head (the part of the rivet that gets "shrunk" to form the grip) on the very thin metal of the rib. I was doing it that way because the manufactured head (the pretty one that doesn't get all squatted down by being riveted) on the side of the metal that would be visible to the outside world. Pure vanity, that, and completely unnecessary. Turning it around and driving with the shop head on the thicker metal worked perfectly. Rick pounded in all four and I headed back to Schmetterling to do the rest. Those were all squeezable because the called out rivets were exactly the correct length.
You can see the shop heads running down the row between the hinge brackets. Please don't look to closely; one of them is pretty ugly. It'll look nice on the inside where no one can see it, though:
The next step is to create a special rib for the bottom of the rudder. This rib will get riveted onto the big welded control horn/hinge bracket. For that to work, the front flange needs to be cut off:
That rib gets attached using a combination of the #4 solid rivets and a couple of blind rivets. I did the blind rivets first:
That whole deal gets riveted onto the spar with eight solid rivets. I was only able to squeeze six; the other two will have to be driven because of interference with flanges and such that precludes getting a straight shot with the squeezer. Well, that and because I insist on successfully driving a rivet by myself.
Tomorrow the rudder skin will go on, so I went ahead and deburred the remaining three ribs and clecoed them into place:
With a few more minutes before I needed to start preparing dinner, I also pulled the blue skin off of the rudder skin.
I worry that the heated language used while doing this puts me in danger of a deadly no-knock raid from the DEA, (they reportedly use thermal imaging spy cameras to detect the heat of the plant lights used for illicit basement farming) so to distract myself I thought about a fun prank I'd like to pull. A fellow brand-new-to-the-whole-game RV-12 builder asked on an internet forum what he should do about primer. The evangelists came flying out of the woodwork like those flying monkeys in the Wizard of Oz, of course, each having exclusive possession of the only possible right thing to do. I got to wondering what would happen if I replied to his question by saying that my plan is to just leave the blue vinyl skin in place on the inside skins, figuring it was put on there to protect the metal, right?
Oh, that would be a riot!
As for your AD4 rivet, make sure you are using the right length rivet. From the picture it looks too long. When a rivet is too length it bends!
This is true, and I remember it from the sheetmetal class that I took at the local A&P school. But.... how could the rivet be too long when the rivet gauge borrowed from Co-pilot Rick indicated that the rivet was, if anything, too short? Sure, Van's warns us in section 5 of the manual that there will be cases where a too long rivet is called out in the plans and may need to be shortened, but... the rivet gauge! How could it be wrong??
Well, as it turns out, thusly:
Used that way, the rivet appears much too short. This is a sample photo taken later with a different size rivet and different thickness of metal, though - with the rivet in question, the error was not nearly as obvious. That said, here's how the gauge is supposed to be used:
Makes all the difference!! I didn't find that out until later, though. Still working under the impression that the rivet was bending because I couldn't get the squeezer situated correctly due to interference from the flange, I hauled everything up to the hangar and pulled out my Gucci rivet gun:
Would you guess that it hasn't seen much use in the last couple of years? Yep, both the rivet gun and me were pretty rusty - I drove a couple of practice rivets in a piece of scrap to remind myself how to do it. Then I aligned everything on the problem rivet, gave it a few shots with the rivet gun, and.....
bent it.
Drat. Having exhausted my limited knowledge without any commensurate gain, I contacted Co-pilot Rick for assistance. I loaded everything back into the car and hauled it up to his shop where he tried to drive a straight rivet. It bent. "Ah," he said, " it's too long."
"Impossible," I replied, "I checked it with the gauge."
You can guess how it went from there.
We used the bench grinder to shave a little length off of one of the rivets and Rick was able to drive it in perfectly straight. Only to find a completely new problem: a gap was created between the rib and the spar. That poor little rib by then had something like the fifth rivet drilled out of it. The newest problem was caused by trying to form the shop head (the part of the rivet that gets "shrunk" to form the grip) on the very thin metal of the rib. I was doing it that way because the manufactured head (the pretty one that doesn't get all squatted down by being riveted) on the side of the metal that would be visible to the outside world. Pure vanity, that, and completely unnecessary. Turning it around and driving with the shop head on the thicker metal worked perfectly. Rick pounded in all four and I headed back to Schmetterling to do the rest. Those were all squeezable because the called out rivets were exactly the correct length.
You can see the shop heads running down the row between the hinge brackets. Please don't look to closely; one of them is pretty ugly. It'll look nice on the inside where no one can see it, though:
The next step is to create a special rib for the bottom of the rudder. This rib will get riveted onto the big welded control horn/hinge bracket. For that to work, the front flange needs to be cut off:
That rib gets attached using a combination of the #4 solid rivets and a couple of blind rivets. I did the blind rivets first:
That whole deal gets riveted onto the spar with eight solid rivets. I was only able to squeeze six; the other two will have to be driven because of interference with flanges and such that precludes getting a straight shot with the squeezer. Well, that and because I insist on successfully driving a rivet by myself.
Tomorrow the rudder skin will go on, so I went ahead and deburred the remaining three ribs and clecoed them into place:
With a few more minutes before I needed to start preparing dinner, I also pulled the blue skin off of the rudder skin.
I worry that the heated language used while doing this puts me in danger of a deadly no-knock raid from the DEA, (they reportedly use thermal imaging spy cameras to detect the heat of the plant lights used for illicit basement farming) so to distract myself I thought about a fun prank I'd like to pull. A fellow brand-new-to-the-whole-game RV-12 builder asked on an internet forum what he should do about primer. The evangelists came flying out of the woodwork like those flying monkeys in the Wizard of Oz, of course, each having exclusive possession of the only possible right thing to do. I got to wondering what would happen if I replied to his question by saying that my plan is to just leave the blue vinyl skin in place on the inside skins, figuring it was put on there to protect the metal, right?
Oh, that would be a riot!
Friday, October 30, 2009
Another riveting tail (tale?)
Not so good, this one. But we'll get to that.
Building the rudder is eerily similar to building the vertical stab, starting with the preparation of the hinge brackets. Being as these are the brackets intended to attach to the vertical stab brackets, though, we are requested to test fit them. The brackets have to be attached to the vertical stab with bolts, which seems somewhat pedestrian after all of the cutting and riveting and other exotic machinations. The bolts needed to attach the hinge brackets to the stab are lumped into a brown paper bag with a collection of other bolts. As one bolt pretty much looks like the next, I had gotten into the lazy habit of identifying them by separating them into piles and determining their type by comparing the number in the pile to the number supposedly included in the bag. By doing so, I also accomplish an inventory of each bag. It was in the bag of bolts that I found my first inventory error:
It was the AN3-5A bolts that I was after, and it seems that I have one too many. That's all well and good, but the karmic balance was maintained through the exclusion of one AN3-4A bolt. I could pester Van's to send me one, but I'll just order one next time I buy other stuff and save them the hassle. They're not at all expensive. Even with the count disparity, I was able to determine which bolts were the AN3-5A and collect eight of them to attach the two hinge assemblies.
The top hinge assembly bolts into the nutplates that were installed early on in the building of the vertical stab. It was when I went to bolt on the bottom assembly that I realized there were no nutplates to bolt it into. My first reaction was to adopt the jaw-dropped look of utter confusion that I get when I try to use a self-checkout at Wal-mart; my second response was to look more closely at the manual. Oh, we tie it on with string or wire, and it will be permanently attached later. I remembered reading that, but hadn't full realized the import of it. Thought it could wait and all that. Luckily, I had some copper wire left over from the canoe debacle as was able to get a nice, tight temporary installation:
With that done, I needed to cleco the hinge brackets onto the spar that will be at the front edge of the rudder. The top hinge bracket is very similar to those on the vertical stab:
The bottom? Well, it's a bit different. It's powder-coated, welded steel. It needs to be far more robust because it also acts as the pair of control horns that the rudder control cables will attach to:
It was finally time to test fit the rudder spar to the vertical stab. This was again a matter of selecting bolts from the little brown bag and using them to attach the two parts. I can see already that this is going to be a real ugly chore when it comes time for the final assembly; it's tough to get the washers between the parts of the two assemblies. After finally getting the first of the bolts and its accompanying washers in, I realized that I had selected the wrong bolts. It was way too short. It seems that the counting and comparing method is not really the best strategy. After a bit of a search through the book that Van's thoughtfully included with the kit, I found a very helpful page printed in a very unhelpfully tiny little font:
After selecting the correct bolts, I repeated the process. The top bolt was even trickier than the bottom with regards to getting the washers in place and I had resort to using some of the left over copper wire to "fish" the washers into place:
Everything fit great. The manual offered the use of thinner washers wherever needed to improve the fit, but that option was not needed at all.
With the test fitting done, the next step was to start assembling all the little bits that will trail along behind the front rudder spar. The first of these is a rib. It gets riveted in through the spar and through the doublers used to strengthen the area where the upper hinge brackets will be. It gets riveted in with the same big, fat #4 rivets that were used to build the vertical stab hinge brackets. Remember how I said that I had read about people having problems squeezing those big rivets but that I had not had any real difficulty at all? You don't? Good! Because I got my comeuppance, good and hard.
The first rivet that I tried to squeeze in bent:
I drilled it out. Here's the head of it impaled on my drill bit:
That just leaves the shaft of the rivet in the hole:
With the thick parts I was working on before, it was a simple matter to just grab the remainder of the rivet with a pair of pliers and yank it out. It's not quite that simple with this thin aluminum. I had to disassemble all the parts and gently pull the remainder of the rivet out without bending or contorting the rib. That was such a hassle that I was extra careful to get the squeezer positioned correctly when I tried again. Well, the good news is that the shaft of the rivet squeezed straight. The bad news? Well....
The head is canted. Crooked. Not flush. Buggered. Lopsided. Sadly, it too needed to be drilled out.
I won't try to squeeze it again. Tomorrow I'll take it all over to the hangar and use my rivet gun to drive it (and the others) in. That will hopefully work better than trying to use the squeezer in the tight quarters of the inner flange of the rib.
Building the rudder is eerily similar to building the vertical stab, starting with the preparation of the hinge brackets. Being as these are the brackets intended to attach to the vertical stab brackets, though, we are requested to test fit them. The brackets have to be attached to the vertical stab with bolts, which seems somewhat pedestrian after all of the cutting and riveting and other exotic machinations. The bolts needed to attach the hinge brackets to the stab are lumped into a brown paper bag with a collection of other bolts. As one bolt pretty much looks like the next, I had gotten into the lazy habit of identifying them by separating them into piles and determining their type by comparing the number in the pile to the number supposedly included in the bag. By doing so, I also accomplish an inventory of each bag. It was in the bag of bolts that I found my first inventory error:
It was the AN3-5A bolts that I was after, and it seems that I have one too many. That's all well and good, but the karmic balance was maintained through the exclusion of one AN3-4A bolt. I could pester Van's to send me one, but I'll just order one next time I buy other stuff and save them the hassle. They're not at all expensive. Even with the count disparity, I was able to determine which bolts were the AN3-5A and collect eight of them to attach the two hinge assemblies.
The top hinge assembly bolts into the nutplates that were installed early on in the building of the vertical stab. It was when I went to bolt on the bottom assembly that I realized there were no nutplates to bolt it into. My first reaction was to adopt the jaw-dropped look of utter confusion that I get when I try to use a self-checkout at Wal-mart; my second response was to look more closely at the manual. Oh, we tie it on with string or wire, and it will be permanently attached later. I remembered reading that, but hadn't full realized the import of it. Thought it could wait and all that. Luckily, I had some copper wire left over from the canoe debacle as was able to get a nice, tight temporary installation:
With that done, I needed to cleco the hinge brackets onto the spar that will be at the front edge of the rudder. The top hinge bracket is very similar to those on the vertical stab:
The bottom? Well, it's a bit different. It's powder-coated, welded steel. It needs to be far more robust because it also acts as the pair of control horns that the rudder control cables will attach to:
It was finally time to test fit the rudder spar to the vertical stab. This was again a matter of selecting bolts from the little brown bag and using them to attach the two parts. I can see already that this is going to be a real ugly chore when it comes time for the final assembly; it's tough to get the washers between the parts of the two assemblies. After finally getting the first of the bolts and its accompanying washers in, I realized that I had selected the wrong bolts. It was way too short. It seems that the counting and comparing method is not really the best strategy. After a bit of a search through the book that Van's thoughtfully included with the kit, I found a very helpful page printed in a very unhelpfully tiny little font:
After selecting the correct bolts, I repeated the process. The top bolt was even trickier than the bottom with regards to getting the washers in place and I had resort to using some of the left over copper wire to "fish" the washers into place:
Everything fit great. The manual offered the use of thinner washers wherever needed to improve the fit, but that option was not needed at all.
With the test fitting done, the next step was to start assembling all the little bits that will trail along behind the front rudder spar. The first of these is a rib. It gets riveted in through the spar and through the doublers used to strengthen the area where the upper hinge brackets will be. It gets riveted in with the same big, fat #4 rivets that were used to build the vertical stab hinge brackets. Remember how I said that I had read about people having problems squeezing those big rivets but that I had not had any real difficulty at all? You don't? Good! Because I got my comeuppance, good and hard.
The first rivet that I tried to squeeze in bent:
I drilled it out. Here's the head of it impaled on my drill bit:
That just leaves the shaft of the rivet in the hole:
With the thick parts I was working on before, it was a simple matter to just grab the remainder of the rivet with a pair of pliers and yank it out. It's not quite that simple with this thin aluminum. I had to disassemble all the parts and gently pull the remainder of the rivet out without bending or contorting the rib. That was such a hassle that I was extra careful to get the squeezer positioned correctly when I tried again. Well, the good news is that the shaft of the rivet squeezed straight. The bad news? Well....
The head is canted. Crooked. Not flush. Buggered. Lopsided. Sadly, it too needed to be drilled out.
I won't try to squeeze it again. Tomorrow I'll take it all over to the hangar and use my rivet gun to drive it (and the others) in. That will hopefully work better than trying to use the squeezer in the tight quarters of the inner flange of the rib.
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