Monday, May 30, 2011

Getting a grip...

What was it I said yesterday? Oh, yeah:

By saying that, of course, I have doomed myself to a prolonged struggle to find the parts...

Remember that? Truer words have often been spoken, but not all that often. I had a plan, though. It's not like I just went off the cuff, assuming that Radio Shack would have the stereo jack or would even be open on a Sunday. I was fairly confident that Wal-mart would be open and that I'd be able to find some bike grips there, so I didn't do much by way of research on that aspect. A perusal of showed that the part number extracted from the Van's plans was, in fact, valid, and that they were open until 8pm. Shiny! Off we went, first stop Wal-mart.

That was its usual treat, winding through aisles crowded with shoppers apparently unaware of their size and the effect it has on others trying to get down the aisles. As coincidence would have it, I stood impatiently waiting behind a slovenly group of five teenagers who were also in search of bike grips, apparently not happy with the ones that were on the bike when they stole it. It didn't seem a difficult decision; there were precisely two choices available. Anyway, there the were, and there I waited.

Done with Wal-mart and on to a nice dinner at Joey Chang's with the co-owner (of my fleet of airplanes and palatial mansion, not the restaurant) before crossing the street to the Radio Shack. The one that was open until 8pm.

Which was closed. So much for - they had closed at 5pm. You just can't trust anything you read on the internet.

I wasn't in any great hurry, anyway. The stereo jack could wait. Still.... keep your web site up to date, Radio Shack!

I tried again this morning at a different Radio Shack. They were open, but this particular store is a perfect example of how things have changed in Radio Shack's market. There was a time when the guy at Radio Shack wouldn't have had to look up the part in the computer to see if they had any in stock, nor would I have had to help him find it on the shelf. Radio Shack today is basically a Subway-sized Best Buy. They're quite capable of selling you a cell phone or a pack of AAA batteries, but beyond that they know little about their own stock.

After watching the employee flail around looking for the stereo jack in the cabling aisle for a few minutes, I suggested that it would more likely be found in the drawers where they keep electronic parts, such as they have electronic parts at all these days. I remember the day when the entire back half of the store was comprised of walls full of resistors, diodes, capacitors, integrated circuits, switches, etc. Now it's all scrunched into a few drawers that seldom see the light of day. Back then, no purchase of components occurred without the employee asking you what you were building. This guy refused to display any personality at all, assuming that he had any to show in the first place. He seemed almost aggressively bored with the entire interaction.

I didn't even ask about the 47k ohm resistors - I just went and found them myself.

I suppose this is the way things are now. We can buy electronic gadgets for less than $20 that would have been unattainable even with the combined billions in wealth of every petty dictator of an oil-rich kleptocracy in the world, or the U.S. Congress, assuming there's much of a distinction to still be found between the two. There's just no point in home experimentation or do-it-yourself electronics experiments anymore. Why dabble with building an AM radio that will cost $75 or $80 once you gather up the components when you can get thousands of stations through your cell phone via satellite?

Still, they're the only game in town and we inhabit the times we live in, like it or not.

I started with the bike grips. The first thing to be done is to remove the end caps. They will need to be drilled to accept the little push-to-talk (PTT) micro-switches that I will someday use to key the microphone in order to talk to the control tower.

The caps came off easily enough, but I could see that they were going to be problematic. Rather than a hollow "cylinder" inside that the switch could fit up into, they had a central spine with rings centered around it. There was going to be no way to fit the switches up inside there. I just cut the spines off. I'll do some duct-tape engineering later to see if I can figure out a way to get the caps to stay on the sticks. If not, it will be no big deal to try a different set of grips. That could end up being another lengthy search; there's no way to see the inside of the caps while the grips are in a package or visible only as a .jpg on a web site.

It also looked like the grip themselves were going to be too long. That was easy to fix with the band saw.

It turned out that I would need to take the control sticks and the grips back home for installation. It's a very tight fit and I'd need to use some dishwashing detergent and water for lubrication. I jumped back to the building of the stereo jack for awhile. The first thing I had to do was match up the little terminals on the stereo jack with the wiring diagram.

The resistors needed to then be soldered onto the stereo jack. I've become quite adept at using tape in lieu of another pair of hands.

To keep the wires/resistors from coming into contact with each other, and also to provide some strain relief for what will surely someday become a troublesome connection (hard wire soldered to a terminal is not consider good practice in the vibration-rich environment of an airplane), I added a couple of pieces of heat shrink.

In an attempt, probably futile, to keep undue bending from occurring on the rigidly soldered wires/terminals, I encased the whole enchilada in another piece of shrink wrap. Thank goodness this part is optional; with this measure of prophylactic protection and foresight, failure is inevitable.

Once the grips were on (and make no mistake - it was a tremendous battle dishwasher detergent notwithstanding), it was time to pull the PTT wires through the control sticks. Millions of pixels have been spilled in documenting the unimaginable difficulty in performing this reportedly impossible task. You see, the stick is anything but straight and not nearly as hollow as you'd expect. And worst of all, there's a ninety degree bend in it just before an obstruction - getting the wire past that is all but impossible. Dozens of solutions to the dilemma have been tried and documented, but all admit to the same sad, immutable fact: it's a pain in the ass.

The solution that seemed best to try first involves pushing a string through and then using the string to pull the wire through. Of course, you can't push up on a rope, and you can't push a string around a ninety degree turn. The best suggestion I have come across described using vacuum to pull the string through. Now if there are two things I have handy in the hangar, they are 1) a vacuum, and 2) string.

The posting I read on the topic said that it would work best to tie a cotton ball on the end of the string to provide some surface area for the vacuum to work against. Now, if there's one thing that I don't have in the hangar, it's cotton balls. I tried a different approach; I tied a little washer on the end.

I started with a goodly length of string, fed the washer down in the top of the control stick, and stuck the bottom of the stick into the hose of my running shop-vac. It sucked that string in so fast that I barely caught it before the loose end got sucked into the top of the stick. It's good that I caught it when I did - had it gotten down in there I would never have gotten it out. Why? Well, note that none of the string has yet come out the bottom.

I figured that the washer was getting stuck against an obstruction down in the tube somewhere and that the strength of the vacuum was sufficient to still keep pulling the string down into the tube despite the fact the the washer was stopped. This convinced me that I didn't need the washer at all; the strength of the airflow was sufficient to pull the string on its own.

I also decided that I'd just pull string off of the spool rather than limit myself to just the length that I had cut. The first few times I tried it, I had no trouble getting string to pull into the tube. In fact, I had trouble providing enough slack on the string because it was going in so fast. Still nothing came out the other end, though.

I reached another decision: the string was getting trapped either at the ninety degree bend or just behind the obstruction soon thereafter. Or both. I decided to feed the string in from the bottom instead. By watching down inside the tube (and, not inconsequentially, exposing my bald(ing) spot to the camera) I was able to see precisely what was happening. The airflow was so strong that it was causing "waves" in the string, much like a flag waving in the wind, and the waves were sticking to the rough interior of the tube. The string would just bunch up in there once a wave had gotten caught.

I found that if I kept some tension on the string as I let it go into the tube and watched inside the tube to make sure string kept to the straight and narrow, eventually enough string would go in that a loop would pop out the other end.

Once the string was through, it was just a matter of using it to pull the wire through. That wasn't as easy as you'd imagine. The first risk was accidentally pulling the wire through from the bottom since that's the way the string had been pulled. That won't work since the PTT switch would then be at the bottom of the stick rather than the top. The other is that the area where the wire is taped to the string will get caught as it tries to navigate the ninety degree turn. Two bad things can happen if your response to this is to just tug harder on the string. First, the string could separate from the wire and you'd have to start all over. The second, and far worse, would be for the little gold pin on the end of the wire to break off.

I got lucky: it was the former that happened to me, not the latter.

Eventually I got both sticks done.

At this point it was well over ninety degrees (what was it with "ninety degrees" giving me problems today??) in the hangar and I was ready to quit, but the next step was to temporarily install the control sticks in the plane. That seems a momentous event, somehow, and what better day for that than Memorial Day and besides, it seemed easy enough.

All I'd have to was add a couple 4.5" tie wraps to hold the wires in place. How easy!

Right. You know exactly what that means.

I have no 4.5" tie wraps. I have a bag of 50 4" tie wraps, but they were too short. I also have six 6" wraps that are probably intended for something else. I'll burn that bridge when I get to it - I went ahead and used them.

With that done, I thought about just heading home, but all I'd need to do to get the sticks in now would be to retrieve a couple of bushings and bolts from the parts bags and put it all together. Piece of cake!

Right. You know exactly what that means.

The bolts would not fit into the bushings.

Hey, it's just a temporary installation anyway, so who needs bushings? It should be easy to just use the bolts.

Right. You know exactly what that means.

The control stick wouldn't fit into the control rod.

That was pretty much it for my patience. I made it fit.

So, there they are! Control sticks in my airplane, even if it is just temporary!

Saturday, May 28, 2011

Surreptitious Research

I've never been one for throwing parties, which is quite likely why I've also never been one that gets invited to a lot of parties. I have quite a bit of the repressed hermit in me, emerging from my preferred solitude only to wear the guise of a gregarious and usually jovial co-worker for as long as it takes to pay the bills. 'Twer up to me, I'd have a shack somewhere in Montana where I'd spend my days building stuff and my nights watching Top Gear re-runs, laughing uncontrollably at their caustically acerbic British wit.

Things are a little different when I'm at the airport, though. Far away from the crowds of Wal-mart shoppers (a term not to be confused with folks that simply shop at Wal-mart, mind you, myself being one. I contend that "Wal-mart" can be a lifestyle in and of itself, separate and distinct from Wal-mart as a destination) and hectic highways filled to capacity with people unable to come to grips with complex operations like signaling turns or using their headlights in the rain, the airport to me is a bucolic refuge in a maddening world. I'm a different, somehow better person there, or so I like to believe, periodic outbursts of emphatic swearing excepted.

Which explains how it came to be that I have agreed to host an EAA Chapter 9 build-visit next month. June 25th, to be precise. 1 pm, if you're thinking of attending.

I myself have never attended one of these soirees so I have no idea what the expectations are for the provision of amenities and comestibles. Do I need to bring chairs? Perhaps a gazebo? Do hosts typically cater in warm foods, or perhaps fondue? Baked goods? Finger sandwiches? Will I be vilified behind my back as a provincial rube for failing to have at least a three member band? Strings, or jazz?

I decided to do some research to find out. Better safe than sorry, as they say. Fortunately there was one such event scheduled for this very day which I thought to be the perfect opportunity for me to take a look at how this business is done. The event was in nearby Delaware, Ohio, and presented me with the option of an enjoyable forty-five minute Miata ride or a ten minute flight.

I opted for the flight, although I was never able to get much above 2,000' due to the low-ish clouds.

Quite the gathering it was! I'm not sure how I will fit this many people into a hangar already packed to capacity with an RV-6 and it's little brother, The Mighty Dozen.

Snacks were limited to a couple of Tupperware containers holding cookies. I personally did not see a single cookie eaten. And music? None but the sound of general aviation itself enjoying a clement Saturday morning.

I can do this!

Back at my hangar, I did a little work on the 12. The first little job was one that will be near and dear to young co-pilot Egg: the installation of the 12V power socket and input jack for a portable music device. Nothing could have been easier. Both parts just screw in, and access was easy.

I had to build up another wire. This one was notable for the fact that it wasn't notable for not providing the required length. In other words, Van's is right back to telling us everything we need to know. I can't figure these guys out.

Next were the pilot and co-pilot headset jacks. These are notable for the difficulty in accessing the holes they go in. With the fuselage being laid on its side like it is, left and right have become top and bottom. As fate and good ergonomic design would have it, these jacks go on the left and right sides, or in the contemporaneous situation, the top and bottom. Not only that, they're installed through the little power transfer panels in the sides of the fuselage. Getting them in there was looking to be a real chore.

Each jack has three washers, one that goes on the inside of the skin and two that go outside. The one that goes inside was the biggest concern. As we've seen before, dropping one of these washers could easily result in it falling to a completely inaccessible area. That would not be good, and would almost certainly result in some non-airport like behavior on my part. Screaming and shouting, as it were.

I came up with a clever little way to keep that from happening. I tethered the washers onto the jacks using slim pieces of masking tape.

Even then I couldn't get my hand in the opening far enough to get the jack to protrude through the hole in the cockpit floor. Lucky for me, I'm horrible at putting my tools away; the Impulse Buy of the Century was still sitting out on the work bench. This it the flebible grabber thingy that I used to retrieve the bolt that I dropped down into the guts of the fuselage. It saved my bacon that day, and did it again today! I just used it to grab hold of the first jack and maneuvered it into the hole.

It held it in place long enough for me to climb down from the stool and run around to the other side.

I used another Harbor Freight impulse buy that I had picked up in their well stocked Dental Tools aisle to grab the edge of the jack and pull it through the hole.

The second jack was a little more difficult. Even with the grabber thingy holding it, it wouldn't sit straight enough in the hole for me to get the two external washers and the nut onto the protruding part of the jack. Masking tape was able to hold the grabber thingy in a better position, though.

Finally! The pilot side is done!

The installation of the co-pilot side is on hold until I can get to Radio Shack. The reason for the delay is that the plans show the optional installation of a headset jack that can be used to siphon headset audio in a video camera. This is a dream come true! I have struggled for years to find a reliable way to do that. My best solution to date is to feed a little bud microphone into the cup of one side of my headsets. It works, but roughly half the time the little microphone gets tugged out of the headset cup and I don't notice until it's too late. I'm definitely going to install the optional jack! Van's was helpful enough to provide a Radio Shack part number for the stereo jack, so it should be easy for me to get the required parts.

By saying that, of course, I have doomed myself to a prolonged struggle to find the parts. It will be worth it.

Thursday, May 26, 2011

Unpublished work sees the light of day!

As it transpires, some of the work on the airplane that I did last Sunday hadn't been reported on yet, the idea being that the relatively small report would segue into Monday afternoon's work and it would make sense to talk about it as if it was a single work session. For reasons I'll discuss shortly, that didn't happen. So here it is, Thursday evening and I find myself looking at these pictures and trying to remember what story they tell.

Ah, yes. It was an interesting task. Close on the heels of the drilling of the hole for the OAT probe which, you may recall, was notable primarily due to the relatively high degree of autonomy foisted unexpectedly onto the builder (in this case, that being your's truly) as to precisely where the hole would be located, we come across a directive to create two [insert esoteric code number that I have long since forgotten here; WH-B183 if I had to guess] wires. Not complicated at all, that, insofar as it entails only the cutting of two lengths of wire and the crimping on of a couple of terminals. Note, however, the arbitrary nature of the phrase "two lengths." We know, obviously, that there are to be two wires. We do not know precisely what lengths they are to be. That is an exercise left to the reader, and I cannot recall a similar instance in which a specific size has not been supplied by the designers.

The wires in question were to run from each of the sides of the fuselage and meet in the center where they would apparently be fastened to the sides of seat ribs to provide a solid electrical ground. With that in mind, I decided that the thing to do would be to first run the entire length of the remaining spool of wire provided in the kit from the left fuselage side, through the wire duct, out to the right side. Then I would leave enough room on the soon-to-be left side wire for it to reach a location on the seat rib. I marked said position with a Sharpie(tm).

I cut the wire at that mark, then pulled some of the remaining wire back from the right side and added a terminal to it. With that done, I simply removed the excess wire from the length pulled out through the hole in the right side of the fuselage. Here are the two wires meeting in the center:

The outer ends of the wires also had terminals crimped on and were then attached to the transfer blocks.

Next I ran some wires back towards the aft end of the plane. This was one of those "might as well; it will only take a couple of moments" jobs that invariably turn into those "why do I ever think anything will only take a couple of moments" jobs. As you can see if you really squint, the wires are going through a hole with no bushing in it.

That sent me on what was effectively an archeological dig through the plans to find the place where I had missed the installation of the bushing, and an even larger search through the archived parts bags to find the bushing itself.

As I said, this all happened four days ago and I haven't been back to the hangar to work since. Sunday afternoon I came down with my annual summer cold and haven't had the clarity of thought required to work on the airplane since. As you can imagine, achieving any kind of productivity at the paying job while working with a brain as mushy as the plot line of a Tarantino movie has been challenging enough; I've had no mental energy left for airplane work after a solid day of trying (and, for the most part, failing) to get more than three or four synapses to fire on command.

I did, however, manage to order a few things. First of all, I had to order more electrical terminals. Some of the really thin 20 gauge wires weren't meaty enough to get the terminals to fully grab onto and the terminals came off during my post-crimp pull test. After the third time that happened, I started stripping a little more insulation off and doubling the exposed wire over before crimping. That seemed to fix the problem, but by that time I was short of terminals.

I also placed an order for two plexiglass bits and a special "zero flute" countersink bit to be used when it comes time to install the canopy.

I mention this because it brings up one of my pet peeves with Van's. Now I may have mentioned before that I have a habit of collecting peeves like a lonely widow collects cats and it really labors the concept of a "pet" peeve to have so many, but this is one that (admittedly irrationally) really irks me. I'm speaking, of course, of their completely inconsiderate shipping practices.

Look, I understand that I'm building a $60,000 airplane and the leakage of a few bucks here and there is small potatoes in a project of this magnitude, but it's just so unnecessary. Because it's so unnecessary, it comes off as somewhat rude.

Here's what I'm talking about. I placed both orders at the same time, and on the same day. Both arrived in my mailbox today.

Here's the Van's order.

Wadded up into a thin envelope. Shipping cost: $6.63.

Here's the Avery Tools order.

Safely packed into a rugged and secure box. Shipping cost: $1.90.

Which of those vendors does the better job of looking out for me, their valued customer?

Sunday, May 22, 2011

The last you'll reed on the subject of reed switches

I can understand the perceived need for some kind of electrical interlock system for these wing pins. What I can't understand is why Van's chose this inopportune moment to stray from the KISS Principle. If it was good enough for Kelly Johnson, it's good enough for me. Magnetism is fine for most of the things it's used for, but I think this particular application was too clever by half. This really should have been done using the same type of mechanical switch used to trigger the stall warning.

But as I noted before, one must press on in the face of magnetic adversity; I had to get these things working. I diddled around with the positioning of the little reed switch, I fiddled around with the positioning of the wing pin. I eventually let the wing pin plunger snap back too quickly and the epoxy that was holding the magnet inside the plunger gave way and the magnet came out. This was actually a good thing - the indications that I was seeing on the multimeter made it look as if it was possible that the magnet wasn't all the way down at the bottom of the plunger.

I decided that rather than just gluing the magnet back in, I'd put the pin in the plane and move the magnet around inside the plunger to see if I could find a positioning that worked. I cleaned up the parts (remember that I had wiped a little grease on the plunger to help it move more freely in the wing pin) and carried the parts over to the plane. I put the wing pin in. Nothing on the multimeter. I pulled it back out of the hole to do the simple always-works test to make sure the wires were all still correctly attached to the multimeter.



I checked the wires and they were all fine. I checked with the other wing pin and it worked too.


I decided to pull the magnet back out of the plunger and try using it directly against the switch.

No magnet.

Uh-oh! I'd lost the magnet!

It couldn't have gotten too lost though; I'd only gone four or five feet from the work bench to the airplane - that should be a pretty manageable area.

Twenty minutes. It took twenty minutes to find that magnet. I was at the end of my rope, convinced that I had looked everywhere that the magnet could have gone.

Then I turned over my drill.

With that problem solved, I returned my attention to the bigger issue: the switch still wouldn't work. I had been shaving material off of the wing pin plunger tube in tiny little increments up to this point, but this was the last straw. I decided to grind away the full 1/8" allowed to me by law.

That fixed it. I did the same to the left side, and it worked too. I'm not sure why I didn't just do that in the first place.

The next page was the installation of the autopilot disconnect switch. While I may not have held the wing pin reed switches in very high regard, I have the utmost respect for the AP disconnect switch. Should the autopilot ever decide to play the fool and run away with the control of one of the flight controls that I feel it is my right as pilot to always have the final say on, I want this switch to put such an affair right. This switch is so important that the autopilot won't even engage if it isn't working correctly. It is this switch that cost me a few trips to Lancaster to try to debug an autopilot problem on a friend's RV-12. The first few hours of that job were spent trying to prove the switch was actually, well, switching. After that experience, I thought it prudent to test the switch before installing it.

It's good!

There's a tiny pilot hole in the panel that has to be reamed out to half an inch. That's just the job for the Uni-bit. With the morning that I had already had, it came as no surprise when the battery on the drill died on the very last step of the Uni-bit.

Once I got just enough charge on the drill's battery to finish the hole, I installed the switch. The wiring of the switch is a little tricky. It has four wires coming out of it; two of them are pretty short. Those get crimped into a splice with a couple of longer wires. Their limited length is such that they barely make it though the avionics shelf bushing. It's a good thing I left room in the aft bushing!

The other ends of the splices get long white wires crimped in, and those wires get fed all the way back to the wiring duct. I don't need those wires - they're for the optional lighting kit that I won't be buying. They provide power to the cockpit lighting that I won't have.  At least not for $1,300 anyway.

"Say," you're asking yourself, "what does the autopilot have to do with cockpit lights?"

A fair question. As I understand it, the Dynon screen that will provide most of the flight and engine management displays has an auto-dim feature that causes it to reduce its brightness in the dark so as to not ruin the pilot's night vision. The autopilot disconnect switch has a little red light in it that will also dim when the Dynon dims. It knows to do this, apparently, from the two colored wires that are spliced in. The white cockpit light wires are also merged into this circuit so that when the Dynon dims, so do the cockpit lights.

Clever, that, and I'd be enormously impressed, if I was buying the lighting kit. I may change my mind someday, so it makes sense to run the wires now. I'll just coil them up somewhere out of the way until such time as they're needed.

The next step of the autopilot disconnect switch is to plug the other, much longer two wires into the big DB-25 connector that will itself plug into the avionics control box. These wires are what were ultimately found to be the problem on that other RV-12 - they were plugged into the wrong holes. That was unfortunate because it required the use of a pin extraction tool to get them out of there. Not knowing how to use a pin extraction tool, I made myself scarce once the need for said tool was discovered.

I swore that I'd get these wires in the correct holes so as not to ever need to figure out how to use a pin extraction tool. The black and white wires on the outside of the black shrink wrap are the wires in question. I'm nearly 100% certain that I got them in the right holes.

"Wait, did you say outside of the shrink wrap??"

Well, yes. Yes I did.

So, here's what the pin extraction tool looks like in use:

And here are the wires correctly installed and inside the shrink wrap:

And here is the shrink wrap, shrunk:

Shrink wrap is pretty neat stuff. You just apply some heat (I have an electric heat gun, but a blow dryer would work) and it tightens up into a nice protective tube.

Which then gets installed into what's called a clamshell or backshell:

Next comes the installation of the Outside Air Temperature (OAT) probe. This probe will tell the flight computer what the temperature is outside of the airplane. That will be used by the computer to calculate true airspeed. In the world of GPS, where we know to a tenth of a mile per hour how fast we're moving across the ground, true airspeed is actually just shy of useless when it comes to any kind of utility in flying, but knowing the temperature outside of the airplane is useful in other ways.

What's notable about this installation is that this is the first time that I've ever had to drill a hole in the plane with nothing more to guide me than "put it right around here somewhere" directions. There has always been at least a pilot hole before.

Oh, also of note is that it's on the left side of the plane, which is currently another way of saying, "Oh, crap! That's gonna be a royal pain to get at."

It was.

With that done, I needed to take the rest of the day off to rest, by which I mean "mow the yard."

Wednesday, May 18, 2011

Reed the directions, dummy!

I continued work on the reed switches today. As a quick review, these switches are part of a too-clever-by-half over-engineered solution to the perceived problem of a pilot trying to fly an RV-12 with no wing pins in place to hold the wings on. In other words, this is an overly complex attempt to prove Darwin wrong. Which is not to say that some form of automatic verification isn't needed, mind you, but because of the persnickety nature of the system as designed, Van's was forced to build in an override switch on the panel in case a failure of this temperamental system stranded someone somewhere. And if there is an easy-to-operate override switch, those already fated to a Darwinian end will eventually use it.

Me? I'm way too smart for that.

It is what it is, though, and I have to get these things installed and working. The first order of business was to gather up the mounting hardware. Oh goody, Adel clamps!! Also note that one of the wires on one of the switches has been modified with the addition of a hoop terminal. This hoop will be mounted onto the Adel clamp screw that holds the right-side reed switch in place. That will provide an electrical ground to that switch. The other wire will be attached to a wire that passes through the wiring duct and is itself attached to a wire on the left-side reed switch. The other wire on the left-side reed switch will attach to a wire that goes all the way back up to the avionics bay where it will feed into a computer. Presumably the computer will send a small voltage back down to the switches and monitor the voltage - when it goes to ground, both of the switches are closed (thereby taking the voltage to ground) and therefore (in theory) the wing pins are in place.

Or something like that, anyway. Like I said: overly complex.

Starting on the right side, I squeezed the switch into its new home in the tight embrace of the Adel clamp.

The clamp gets mounted under the passenger arm rest, and getting that clamp in there was a real bugger. There was no room for fancy helpers like safety wire or vise grips; it was just a bare-handed fight to the finish. Once I finally got the clamp secured, I tested the circuit by putting the wing ping plunger right up next to the little hole that allows the reed switch "see" through to the other side of the arm rest. The needled on the multimeter being way over to the right like that means that there is no resistance on the switch, which in turn means that the switch is closed. In other words, it works.

Putting the pin in place didn't work at first, however. It took a lot of wiggling and monkeying around with the switch to finally get it to work.

If I thought getting the Adel clamp in place was an onerous chore, it's only because I hadn't yet tried passing the wires through the two tiny little bushings in the frame and didn't have a good basis of comparison. It was like threading a needle with string before then trying to blindly thread yet another needle three inches away. It didn't take long to see that it wasn't going to work. I went and got a length of safety wire and tried passing it through the bushings, the idea being that I would tape the wires to it and pull them back through the bushings. I couldn't get that to work either, and eventually resorted to using an inspection mirror to get a look behind the frame to aid in getting the safety wire correctly aligned with the second bushing. Success!

Having completed the right side, I went back to the work bench to get the left side switch. You may remember that the left side switch is the one without the hoop terminal on one of the wires.


And I'm the guy that's too smart to ever forget to put in a wing pin!!

Hello, Mr. Darwin.

So, long story short shortened, I removed the incorrect placement of the first switch, replaced it with the correct switch, then installed the first switch on the left side of the plane where it was supposed to be in the first place.

I then tested the switches again.

Neither would work.

Checking the book, it says that I may have to file off some of the wing pin tube that the plunger resides in. In fact, I am allowed to remove up to 1/8". This will expose more of the plunger to the tiny hole that the face of the switch "looks" through.

Having researched this in advance, I knew that this was a likelihood. I also know that there are other approaches. Some have repositioned the switches to make them align in parallel with the plungers, while others have increased the diameter of the "view" holes to improve the magnetic view for the switches.

I'll try the grinding first, but if it doesn't work I will probably enlarge the view holes a little bit.