ELT - Flap System - Antenna Mount - Misc

Happy Veterans Day! It's been an interesting year, getting used to my new job where we observe all of the federal holidays and have the day off. Not that I'm complaining of course... more time to build! :-)

Today was an excellent day making progress in a number of areas. I started off by installing the ELT mount in the tailcone, which went fairly quickly even though it was a bit tough getting access to install blind rivets in all the holes between the mount and the J-stringers behind it. I ended up stacking two #6 locknuts on the rivet stems so that my rivet puller could get the grip it needed for the job. About 20 minutes of this combined with some awkward leaning, and the mount was in!

ELT mount installed, sans ELT

ELT mount installed, with ACK E04 ELT

Cool! Looks "official" now. You may notice that the mounting tray is not parallel with the tailcone stringers. I'm using the door sills as a reference for level, and discovered that the stringers in this location actually slant upwards just slightly. I used a level to approximate the angle here, and I believe it turned out pretty darn close. I have a 10-degree tolerance per the installation requirements anyway, and I'm confident that it's well within that. (EDIT 11/15/2015: A tip I later discovered, kind of an "oh, duh!" moment: if you have a smartphone like an iPhone with a compass/level app, you can use it as an inclinometer and get very accurate measurements to the nearest degree! Turns out this ELT is approximately 2 degrees off from perfection. Well within tolerance, but I could have done it perfectly if I had been thinking!)

Next on the agenda was to start assembling the flap system. Oops! Quickly discovered that before I do any final installation in this area, I'll need to install my belly-mount COM antenna doubler that I want to put in this location. So, on to that.

I chose this location for the antenna for a couple reasons. First, I wanted the antenna to be in the tunnel area so that it is always accessible from the inside. I've seen a number of builders (the majority, in fact) use the area under the rear seat to mount a COM antenna, but that just doesn't sit well with me. If you ever have to gain access to this area for whatever reason, you'll be drilling out hundreds of rivets and removing a pretty large part of the cabin floor. So I made the decision early on to put all the belly antennas in the tunnel area (I think there will only be two: this COM antenna, and a transponder antenna further forward).

The second reason for choosing this *exact* location in the tunnel beneath the flap torque tube is a bit of  accidental chance. Way back when we were first joining the forward and mid fuselage sections together, Sarah had a bit of an "oops" moment with the tungsten bucking bar, which had slipped from her hand and went flying through the air. In a slow-motion "noooooooooo!" sequence, fate steered the bucking bar's trajectory straight toward this area of the tunnel, resulting in a solid "clunk!" and producing a nasty outwards dimple in the bottom skin. We learned two things from this event: (1) Install an antenna in this location; and (2) secure the bucking bar to Sarah's hand with duct tape. Just kidding, of course. We weren't actually sure if we would install an antenna here yet ;-)

Reading some of the other build blogs online, I discovered that fellow RV-10 builder Justin Twilbeck actually had a similar mishap (see his blog post "Dent Happens" here) and decided to put an antenna at the scene of his accident as well! Funny coincidence.

Anyway, this location actually works out perfectly, as it is right at the "hip" of the fuselage, at the aft-most part of the bottom before it takes a turn upwards. I believe it really is actually an ideal location. So, I got started on making a doubler to place over it. I found a template for the hole pattern for the Comant CI-122 and used it to start making the doubler, and ended up with this part:

Comant CI-122 doubler, prior to enlarging circled holes for antenna connector and mounting screws (also added another row of holes near the left side in this photo)

After a bit of match-drilling to the fuse bottom skin and enlarging the holes, I was able to shoot the piece with primer quickly and await Sarah's return home from work to finish dimpling and riveting the piece into place. In the meantime, I continued with some miscellaneous tasks left over from the previous sections, including running some conduit along the right side of the baggage area and installing the cover panel, as well as installing the cover panel on the left side of the baggage area behind the rear seats. Lastly, I installed a number of nutplates that go in the various locations along the interior of the fuselage to secure cover panels and such. About this time, Sarah got home and we proceeded to dimple the bottom skin and rivet the antenna doubler into place:

Antenna doubler installed in tunnel. Antenna is offset slightly to provide clearance for elevator push rod, visible on the right

Comant CI-122 screwed to the bottom of the fuselage

Looks neat! I didn't have long enough screws for a permanent installation, but they worked perfect for a trial fit. Seems pretty solid and sturdy here and should work great!

For the final chapter today, I finally got to what I had set out to do earlier today, which is to install the flap system. I had already drilled and prepped most of the parts on a previous day, so today it was really just all about installing everything into the plane. I quickly discovered my first issue, which was that the holes in the fuselage side skin were too small to fit the flap torque tubes. I couldn't figure out any other way to get both tubes into place, and ended up enlarging the skin to match the underlying holes at 1-1/16". Then the next challenge was installing the UHMW bushings and getting everything oriented properly. I discovered another problem: the cutaways for the powdercoat weren't exactly in the correct locations on the torque tubes! This caused a huge increase in friction, and the tubes were very difficult to rotate.

L torque tube inner end, line drawn where bushing extends to

Each of the four locations had varying amounts of overlap, so I traced lines on all ends and carefully ground away the powdercoat, and polished the surfaces on the scotch brite wheel afterwards. Re-installing the tubes showed a dramatic reduction in friction! Good stuff.

So after about an hour of bolt-installation and rigging, we had the whole works put together!

Sarah is happy. Please move your hand though so we can see!

There we go! Flap system installed and ready to go

Sarah wanted to take a picture of me tightening the last bolt holding the actuator to the torque tube arm (visible above with no nut)

With that, we were able to hook a drill battery up to the flap motor and presto... The flap arm appears to work perfectly!! Wahoo! This is the first electrical part that is permanently installed to the airframe now. Exciting times. We ran the flaps up and down a couple times until the excitement wore off a bit and decided to call it a night. Big day of building today, and all ended up going very well! Tomorrow if the UPS gods are shining on us we should get some more fittings to satisfy our insatiable appetite for Aircraft Spruce packages, and we can continue with the fuel system. Maybe we'll also get to install more of the control system, even the control sticks! 'Stick' around!!

Rear Seats - ELT Mount Part 2

Finished Section 42 tonight! Yikes, running out of things do to in the fuselage kit short of the Cabin Cover. Got some time in over lunch today for a quick priming session. Primed the components for the rear seats, the elevator control rods, and the ELT mount that I had fabricated the other day. Got back to it after work and was able to rivet the rear seats together in fairly short order. Unfortunately Sarah had to proctor a pilot exam at the airport so I was flying solo tonight, so to speak. Derek came over for a bit to watch the excitement though, and before long both rear seats were set into position!

Custom 60/40 Rear seats, riveted together and laid into place

Right "40" seat leaned forward to show split

The whole assembly took about an hour, maybe less, to rivet together... awesome! Getting good at this riveting stuff, now that we're getting close to being done with most of the rivets on this plane. Oh well. Next thing to do was rivet together the ELT mount, which looks like this:

ELT mount riveted together

It's a fairly simple part made out of 0.063" aluminum sheet, two angle aluminum pieces to mate up with the stringers in the tailcone, and a short piece of J-channel going vertically between the angles. I'm not sure if I needed to use aluminum as thick as 063 but I had been dabbling with that thickness for the panel, had some scrap handy and figured why not. I think I could have probably used 032 and an extra J-channel instead, and saved a fraction of an ounce or something in weight. I would like the ELT to be mounted as securely as possible though, not only for obvious reasons, but also if we want to follow DO-204 compliance standards, taken from paragraph 3.1.8:

"The mounts shall have a maximum static local deflection no greater than 2.5 mm (0.1 in) when a force of 450 Newtons (100 lbf) is applied to the mount in the most flexible direction.  Deflection measurements shall be made with reference to another part of the airframe not less than 0.3 m (one foot) or more than 1.0 m (three feet) from the mounting location."

I'm not sure if I've heard of anyone ever actually test this, but the point is we want it to be as solid as possible. I believe that this part should easily satisfy this requirement. Anyway, that was pretty much it for tonight... I have tomorrow off from work so hoping if all goes well it will be a big day in the factory to make some good progress!!!

Rear Seats - ELT Mount

Finished all the prep work for the rear seats today! Started by trimming and drilling the upper F-637C braces that nest inside the upper edge of the seat backs. This was pretty much the trickiest part of the whole section, although it really wasn't that bad. The vertex of the pieces need to be rounded in order to properly nest inside the seat back. I figured out a way to do this by carefully holding the piece up against the fence on the bandsaw at a 45-degree angle (so both flanges are in contact with the fence), which presents the vertex to the bandsaw blade at the perfect angle to neatly trim it off. You have to be careful to set the fence in the perfect position so just the right amount gets trimmed away, otherwise you'll end up with two separate flanges and a frown.

The vertex of the aluminum angle being fed into the bandsaw

View from above

The trimmed vertex, after a bit of cleanup on the belt sander

After drilling and clecoing, I was able to place both rear seats into position for a photo shoot:

The back seat frames!

Rear seats with custom 60/40 bench modification (center piece not yet trimmed)

Closeup of the 1/4" gap between the two halves

I had previously marked a cut line for the center F-637A seat back panel so that it doesn't overlap so much of the left side panel. Once everything came back apart, I made the cut and deburred all the parts. This was the first real deburring session in a while, it felt... great.

Finalized rear seat back parts, after deburring, ready for primer!

Next, I got to work on the ELT mount. I had previously made a mounting tray while building the empennage kit out of 0.040" aluminum sheet that was bent using my home made brake to go between two of the stringers in the tail cone, directly to the right of the battery location. Although I like the location, I didn't like the quality of the tray I made. I felt like I could do better with two pieces of aluminum angle and a flat (not bent) piece of aluminum sheet. So, I took a few measurements and got to work on "v2.0" of the ELT mount. It came out pretty good, I'm very happy with it, although I don't have any pics of it yet. I think I primer session is in our future pretty soon, and we'll be able to have a number of parts ready to rivet and final-install into position.

My fuel fittings should be here sometime this week, and we'll be able to get back to business on sections 36/37!

Rear Seats, More Panel/Tunnel/Center Console

Started off this morning continuing with the panel mockup and layout. I had a new idea that I think I'm going to move forward with regarding the placement of the GMC-307 autopilot controller. I'd like to put it at the top and in the center of the panel, where you see flight control panels in many larger aircraft. The problem is, there is a support rib behind the panel in this area that Van's doesn't want you to mess with. I know of many people who have messed with them anyway and come up with their own methods of stiffening them, but I'd like to avoid that if I can, especially with the center rib that also is a load path for the cabin cover. Since the GMC307 isn't a very deep unit at less than 1.5", I had an idea to make a little "pod" to put it in and place it in front of the panel, screwing it to the underside of the upper skin and securing the back side to the panel. This way, I won't have to mess with the support rib, and the control panel will be in an even better position! So, I made the front face panel for a "pod" that measures 2.5" x 9" with the bottom two corners radiused. Looks pretty neat! Now to just build the remaining structure and make it look good...

Additionally, I got to work on other parts of the panel including the bottom support brace (some people call it the "switch bar"). It always bugged me that the way it's designed, it doesn't sit flush with the panel and is layered behind the panel itself. So, I made up a 1" wide strip of 0.063" aluminum and match-drilled it to the switch bar to bring it up flush with the panel. I think I'm going to install switches either at or near the seam between the bar and the panel, and then trim the seam with some chrome accent. It looks cool in my head, we'll see if I can make it a reality :-)

Doing all this with the switch bar made me re-think the center console idea a bit that I had earlier. I can make a panel out of 0.063" aluminum and insert it into the middle of the strip on the switch bar, making a perfectly seamless and flat transition from the lower console to the panel! So, I grabbed some more 0.063" sheet and got to work making another center console. I like this WAY more than the piece I made last time. For "cool" factor and more mockup purposes, I got out the fuel selector and the throttle quadrant and set them all into position for a photo.

N165MJ Panel Mockup #2

I think this should work nicely! Oh, and don't mind the armrest. I had a few people ask about it, I got it off ebay for about $30, it's for a Nissan Versa I think. It's about the right size, but it's also about the quality you'd expect for an aftermarket auto interior part sold on eBay and shipped direct from China. It also has a nice little toll change tray inside, which will come in super handy for all those fly-through toll booths you see from time to time. So, I don't think this is "the" armrest for this plane, but it is at least "an" armrest that I can use for mockup purposes, and maybe build my own that will be similar but better, and integrate the quadrant to it.

The last thing I did with the panel shenanigans was cut the tunnel cover at the point where the console meets the cover. This way, the middle part of the cover can be removed without pulling out all the avionics behind the panel if the fuel valve, parking brake, controls, etc need adjustment or service. Pretty straightforward deal, hoping it works out nicely!

With that, Sarah wandered out into the garage (panel stuff doesn't interest her... silly girl :-P) and we continued with the rear seats. Lots of measuring, marking, drilling, and clecoing. Eventually we had both sides drilled and test-fitted into position. Then we grabbed my extra F-637A seat back and laid it over the F-637A already in place for the left seat, and slid it out until it was 1/4" away from the right side seat. A few match-drills later, I think we were able to pull off making a 60/40 split bench backseat with minimal extra parts and effort! Pics to follow.

That's it for tonight, I think tomorrow we'll probably just continue on the back seat and get that finished up. Getting close to being "done" with everything except the cabin cover....... fiberglassing is imminent!

Brake Lines - Rear Seat Backs

Productive night tonight! Now that the parking brake valve mount has been made, we can start with actually fabricating the brake lines. There are a total of four brake lines to make: One under each front seat going from the landing gear mount to the tunnel (where the parking brake valve is), and then one on each side of the tunnel going forward from the valve and up the firewall, terminating at a bracket on the upper left area of the firewall. I'll be making these runs out of 5052-O aluminum tubing, which is a stronger material than the provided 3003 alloy in the kit (3003 is not used on brake lines in production aircraft). This is a common upgrade that I decided to go for and had previously ordered the necessary lengths from Aircraft Spruce.

Meanwhile, Sarah came out and first helped rivet the parking brake valve brackets to the bottom fuse skin in the tunnel, and then decided to start working on the rear seats (Section 42). We're going to try a small modification here and make the back seat more of a 60/40 bench-style seat as opposed to individual buckets. Cleaveland sells a kit to do something similar (with headrests and all), but we're going to try to keep it simpler and just extend the left-side seatback using an extra F-637A seatback panel which I added to my finish kit order. So in the meantime, Sarah can still make many of the supporting bits needed to assemble the seats. No pics yet of these parts, but she made a number of parts out of aluminum angle to form the structure of the seat backs.

Back in Section 36, I got started on bending brake lines. The first ones to make are the ones that go under the front seats. They are relatively straightforward, and I began using a technique I read about on the forums, where you take a piece of solid-core copper house wire and bend it to the desired length and shape, and then use that as a template to make the actual brake line.

Copper wire cut and formed to desired shape for brake line

Using the wire as a template, I got out the 1/4" 5052 tubing and used my OTC 6515 tubing bender to make the same part out of brake line:

5052 tubing bent to shape from wire template

In this way, I made both brake lines that go under the seats, and decided that was enough for tonight. It turns out Sarah finished making her brackets but didn't feel like busting out the drill, and I had finished my two brake lines but didn't feel like busting out the flaring tool. Still a very productive evening, and with a few more nights like this we might have two more sections crossed off the to-do list!

Interior Paint #2 - Section 39 Begin

Started off Saturday by stripping all the paint off the firewall, using a bit of Rustoleum "Aircraft Stripper" and loads of acetone on a paper towel. This was one of those lessons learned the hard way: Spend the time up front masking off the areas you don't want to paint so that you don't have to spend hours later on stripping it all off. Ugh. Oh well, in the end it all worked out.

All this paint stripping got me thinking: how much smoke really comes off the paint in the event of a fire? I've heard rumors that it creates thick, acrid, toxic smoke and can really make a life-or-death difference in the outcome from an in-flight fire. That was enough for me to take it seriously and strip it off. But, the engineer in me wanted to see exactly how much smoke comes off of this in a fire. So, I grabbed a scrap piece of aluminum that had been scratched beyond usability while installing the rear floor pans (remember my method for inserting them?). I had a love-hate (mostly hate) relationship with this particular piece of aluminum, so I was happy to spray it with some Rustoleum Hammered Black and take the torch to it. Here's what I saw:


It actually didn't smoke nearly as much as I thought it would! And the smoke didn't really have too much of an acrid or toxic smell. Not that I'd intentionally breathe the stuff, but it was a bit of a relief that it didn't blow up into a thick plume of nasty smoke or anything. Good data point, I guess. I still went through with stripping the paint off the firewall though, because it can't possibly hurt.

Once the firewall was stripped, I was able to mask everything again properly and spray another coat of paint in the areas that needed it. I went through the predicted two cans and left it to dry. Now... on to Section 39!

Whoa whoa whoa, Section 39, you say? What happened to 36-38? Well, I wanted to get started on the brake lines (36) but before I could do that, I wanted to make sure there would be clearance for the parking brake valve to go under (or at least near) the elevator control linkages, which are assembled in section 39. Additionally, section 39 is the first part I can actually work on and not need to be inside the fuselage, where the paint is still drying. So, off to make some aluminum control rods and brackets:

The F-1089 Elevator Pushrod

In total, I made three pushrods today: the F-1089 pictured above, the F-1090 mid-fuse pushrod, and the F-1091 pushrod that goes in the tailcone (plans in section 11 from the emp kit)... over 13 feet of pushrod in total! The next step was to final-drill and assemble the F-1063 Elevator Idler Arm, which unfortunately I didn't take any pictures of. It was a fairly straightforward piece to assemble. After that, I drilled the control sticks, which went fairly well too:

Drilling the control stick and pivot base

Not bad! Cruising right along in Section 39. Also, I was able to temporary-install the WD-1010 control column and figure out how much room there will be for the parking brake valve... looks like we'll be good to go for that! Will have to custom-make a mount for it and get it situated, will post pics of that later. Until then, more watching paint dry!

Section 34 Complete - Oil Cooler Mount - Interior Paint 1st Coat

Busy weekend! Started off Saturday morning attending a EAA Young Eagles event in Tipton, IA (8C4) and providing some ground help marshaling planes and escorting guests around the ramp. We had a great turnout, and it was awesome to see so many people from our chapter (#33) present. Two certified aircraft showed up-- a Mooney and a 172-- in addition to that though we had 5 experimentals including 3 Long-EZ's and 2 RV's giving rides! Very cool to watch our chapter pilots do what they do best in some gusty crosswinds at an airport that had some fairly challenging and wind-jumbling trees and terrain. Smiles all around!

After that though, it was time to get back to work and finish up the last remaining part of the baggage door: the F-1031 frame. My idea was to install a micro switch inside the frame, and put a small access cover in place of the original striker plate that would normally be there. After taking a few measurements and marking off the piece, I ended up with this:

The F-1031 Upper Baggage Door Seal Channel after installation

I don't have a pic of the cover plate or the micro switch, but the switch is attached to the cover plate and has a small steel wheel that protrudes out the back side (inboard side) of the channel. When the baggage door is closed, the latch catches on this wheel and pushes it in flush with the channel, activating the switch. This way, even if the door is fully closed, but the latch isn't latched, the switch will still indicate that the cargo door isn't properly closed. Should work pretty slick!

That puts an end to Section 34... yay! Before moving on to interior paint, I decided to assemble and install the oil cooler mount that I had custom-modified a few weeks ago to accept a larger-sized cooler. It went fairly well, although a few of the rivets along the top were fairly difficult to access. I ended up having to install just the top flange by itself to the firewall, allowing me to bend it down quite a ways to access the top row of rivets, and then assemble the rest of it as it got attached to the firewall. The resulting product looked great!

Custom oversize oil cooler mount, final installation - L side

Custom oversize oil cooler mount, final installation - R side

EDIT 11/1/2015: I think I may have messed up. Now that the finish kit is here, I see that the engine mount will actually get in the way of the larger oil cooler. I may have to redesign this mount from scratch, we'll see. Keep looking for updates on this.

The next order of business before we start bending brake and fuel lines is to paint the interior. Most parts of the interior will be carpeted or upholstered anyway, but the idea of painting the interior is to give the underlying structure a kind of consistent "base" color so that you won't see any unpainted surfaces in all the little nooks and crannies that won't be covered up. I've decided to go with a simple and inexpensive rattle-can paint, Rustoleum "Hammered" Black. The hammered pattern should give a nice look and spray on relatively easily.

I spent about an hour or so masking off all the parts I didn't want to get paint on, and in retrospect I think I should have spent even more time. More overspray got inside the tunnel and under the front seat than I had anticipated, which isn't a huge deal but it would have been better if I could have kept it brighter white. I may try and repaint it white or leave it alone, we'll see. Also, I never masked off the firewall so it ended up getting painted too. Not sure how I feel about that, we'll see how well it adheres to the stainless.

The first coat took 4 cans, and came out relatively well. It got a little blotchy in a few areas where I started to run low on paint, but I'll wait the recommended 48 hours and throw another light coat on. I imagine 2 more cans ought to do the trick. I'll also need to paint a number of other panels off the plane, so I'll probably need a total of maybe 4 more cans. Here's what it looks like so far:

Aft interior section after painting first coat

Forward interior section after painting first coat

That's it for now! We'll give this first coat 48 hours to cure and then try and shoot a light second coat over it and see if we can fill in a few of the light spots. Stay tuned for that!

Section 35 Complete!

Knocked off another section this weekend! By far the hardest part about this section was installing the rear floor pans, discussed in a previous post. The rest of it is really for the most part final-drilling a bunch of #19 holes, dimpling a bunch of #8 screw holes, and maybe the occasional nutplate installation. Easy peasy. Of course, this section isn't really ever "complete" until every last panel has been upholstered/painted and then screwed into position, but that's not necessarily going to happen until the plane is ready to fly-- certainly not until a number of other systems have been installed like the flight controls, brake lines, fuel lines, and wiring. So, I'm calling this section "complete" but really there's just a pile of bare aluminum panels that still need to be painted or upholstered. That will come in time!

Some of the access panels in place (shown unprimed)

It's hard to get the whole bird in the photo nowadays... not a bad problem!

Oh! I almost forgot. Spent a good amount of time this morning modifying the oil cooler mount that I had added to the fuselage kit. Because my engine has the piston cooling oil nozzles, oil cooling needs to perform better than similar engines without this feature (with the positive tradeoff of lower and more stable engine temperatures overall, of course... at least that's the theory). Due to this, I will be using a one-upsize oil cooler, the Airflow performance 2008X. This cooler is the same width and thickness as the stock one, but is about 1-5/8" longer. The mount, then, will need to be modified to accept this larger unit.

The stock VA-186 Oil Cooler Mount

Spacer brackets fabricated to extend the cooler's length

Modified VA-186 mount to accept Airflow 2008X Oil Cooler

EDIT 11/1/2015: I think I may have messed up. Now that the finish kit is here, I think the engine mount will actually be in the way of the larger oil cooler. I may have to redesign this thing from scratch, we'll see. Keep looking for updates on this.

In theory, it's not a very difficult modification. However, it ended up taking about 4 hours to get it just right. Basically, I separated the top plate of the mount from the rest of the assembly and fabricated a few spacer extensions to lengthen the open area for the cooler.. By changing the angles that the cooler originally sat at by a small degree, it retains the same footprint on the firewall and now accepts the larger oil cooler. Cool!

Speaking of cool, we've arrived at kind of a "cool" pivotal spot in the build. Most of the metalwork is done, at least as far as the primary structure of the airframe is concerned. Of course we have by no means set our last rivet, but everything from here on out is really pretty minor as far as aluminum work goes. From here onward, the majority of tasks are going to be centered around plumbing, wiring, control systems, and of course FIBERGLASS. As with many builders before us who have gotten to this stage, we've sorta procrastinated on some of the smaller glass tasks that have presented themselves along the way, and now have a stack of small bits to make as well as a couple large ones. I've heard from many builders that the canopy top and doors are some of the most time-consuming and painstaking parts of the build, and make up for a substantial portion of the total build time.

Also, it's time to start buying "stuff." Everything from wiring, stick grips, fuel lines, brake lines, the rudder pedal system, custom tidbits/upgrades, antennas, lighting, upholstery, and even the beginnings of some avionics. This is both exciting and depressing, as it is going to require careful management of monthly expenses and planning out the logistics of what needs to be bought and when. The UPS guy, if he doesn't already, is going to start to remember this house over the next few months! Who am I kidding, he's gotta already know us :-)

Over the next few days, I'll be assembling a list of things left to do before the finish kit arrives (don't worry, there is still PLENTY to do, I just need to make a list and organize/prioritize). Among the next things to do: (1) measure custom lengths for brake/fuel lines and decide if we're using flex or solid lines, probably a combo of both; (2) paint the interior; (3) continue with the baggage door after my latch arrives; and (4) begin fiberglass work.

Until the list is complete though, marathon-nights of extreme building may be replaced by marathon-nights of extreme reflection on what to do next and how to do it. The metamorphosis from builder to philosopher begins....

Section 35 Begin

Started Section 35 - Access Covers and Floor Panels today. The first thing they have you do is prep and rivet the rear floor pans into place. I got all the holes drilled, deburred, dimpled, scuffed, and primed in fairly short order. Riveted a few nutplates to the bottom side and thought things are going quite nicely so far, all that's left now is to drop them into place and rivet them down! I must say, this part of the plans caught me by surprise how difficult it was. In my mind, I thought "it's a bunch of blind rivets, should take 10 minutes" but in reality there are a number of solid rivets all around the perimeter, you have to match-drill into the center section spar, and worst of all the panel itself is *extremely* difficult to wedge into position.

The floor panel has three cutouts along the forward side that are supposed to go around the seat brackets and the middle reinforcing hat channel attached to the spar. Well, on mine (and others I've read about) the cutouts were just a tad too narrow to fit around the seat brackets, and this makes installing the floor impossible. It's not evident right away that this is the problem unless you're specifically looking for that, and that's what makes it tricky. Instead, you'll just want to push harder and harder until SNAP something gives. Usually it's the flange on the side of the panel that will buckle. If you're lucky (like I was) it didn't crack, it just bent a bit and I could straighten it back out.

Well, after salvaging my screwup on the L floor panel and getting it all riveted into place, I thought I'd be a hero and take a million photos of the method I thought I had "perfected" now for the R floor panel to show others "the way"... here's what I came up with:

Fiberfrax insulation laid out, and two scrap sheets of thin aluminum to help the panel slide past the seat belt brackets and rivet heads

Panel laid into place with the aluminum sheets on the side helping it slide down

Check for appropriate clearance around the seat brackets

Take an automotive panel/upholstery pry tool to help wedge the panel from the backside

Now just pry it forward to clear the rear spar center section, give her a little push, and....

OWWWWEEE.

Oh for crying out loud! It was going so perfectly too. Just a bit too much pressure in the wrong spot and the damn thing buckled again... this time causing my hand to slip and go right into the sharp, unfinished corner of the aluminum sheet I had so proudly put in place to guide the panel down. So much for a flawless install procedure.

The buckle in the floor panel. Again like the L side, it didn't tear or crack thankfully and could be straightened out by careful and judicious use of the flush rivet set on the 3x gun.

So, in all reality it wasn't the worst situation in the world to be in. Got my hand all patched up (yes that's electrical tape holding the band-aid in place), stuck in a bunch of clecos and straightened out the buckle. In a few hours' time I had both panels fully riveted into place, and a very sore back from sitting in a number of incredibly awkward positions:

L floor pan after riveting

R floor pan after riveting - buckle is erased thankfully!

Whew! Glad that bit is over. Note to future builders: good luck! These floor panels stink. But, when they're done, you have a nearly complete floor in your entire airplane.. yay!

Tomorrow if there's time we'll probably rivet down the rest of the back seat panels (they were left up to provide access to riveting the aft edge of these floor pans) and continue with Section 35!

Section 33 Complete!

Well... sort of complete, anyway. Today I worked on the second half of Section 33, which dealt with installing a cover panel on the R side of the baggage compartment (opposite from the door) and drilling/deburring/dimpling holes for the baggage bulkhead corrugation panel. I say "sort of" complete because there are a couple parts that I will be leaving uninstalled for now, namely the R side cover panel because I want to make another conduit run behind it to put wires that I want to keep separate from the other two "main" looms. I had ordered some 3/4" conduit from cableorganizer but for whatever reason it's been delayed an extra couple weeks.

Guess it's a good time to vent about cableorganizer.com. It's been a bit frustrating dealing with them, so far they are my least favorite vendor I've dealt with on this build. They charged/re-charged/refunded my credit card a number of times for some reason which triggered a fraud alert that I had to deal with. When I originally placed my order, everything was said to be in stock, but suddenly one item (zip ties) mysteriously changed to a ship date of 8/31. No big deal. The 3/4" conduit in question though was marked as shipped with the rest of the order on 8/19 (which by the way was 6 days/4 business after the order was placed), however it wasn't in any of the boxes that arrived. When I called to inquire, I was told it wouldn't ship until 8/31, along with the zip ties. This was *not* what was clearly printed on the invoice and all order tracking notifications I received. Grr. Maybe I'm just used to places like amazon and aircraft spruce that ship within a day or so, and seem to be much more "on top of it". Or maybe I'm just bitter about spending over $250 on plastic tubing and zip ties... :-/

Anyway...... first-world problems I guess. The rest of Section 33 went pretty well, and I now have a number of nutplates installed around the perimeter of the F-1006 bulkhead and down the F-1028 channel.

Drilling the #19 holes around the F-1006 bulkhead

Panels removed and nutplates installed!

In the pic above, you may notice that the F-1031 Upper baggage door seal channel is not yet installed. I'm also leaving this part out for now until I figure out exactly what I'm doing for the baggage door latch. I'm not crazy about the idea of the standard key-only latch mechanism; I'd rather have the ability to lock-unlock it and then have some kind of paddle handle or slide latch to open and close the door. I'm searching far and wide for the "perfect" latch and it's been kind of hard to find so far. I'll keep searching, and I don't think that will really keep anything else from continuing in the meantime.

I also finally installed nutplates along the forward tunnel along the top edge. Technically this was supposed to be done a while ago (I think in the firewall section?!) but I kept procrastinating, knowing that it could be done at basically any time since there is easy access to that area. No worries, that's done now too.

So, all that's really left to do with Section 33 is final-installing the F-1080 baggage cover once I finally get my conduit, and final-installing the F-1031 baggage door channel once I figure out what my baggage door latch is going to be. Oh, and installing the rear seat belt wear blocks, but again I want to hold off on that until I actually have my restraint system purchased and in-hand. Three quick and simple tasks... good enough for me to call 33 done!

Next up, I'm going to skip 34 (baggage door) for the same reason as above until I find the right latch, and going to start on 35, Access Covers and Floor Panels. Should be a fun section, hopefully!

Baggage/Rear Seat Floors

Productive day today! Primed all of the parts needed to complete the first half of section 33 over lunch and then got to work laying insulation and riveting the floors into place! Similar to the forward floors, I used a layer of 1/8" Fiberfrax insulation, and topped it with Ultratouch under the rear seats only. Under the baggage area, I used aluminum tape to secure the relatively thin and light Fiberfrax.

Insulation laid up, ready to install floors!

I started riveting the floors on and realized my pneumatic rivet gun wasn't working right. It started taking two, and then three squeezes to actually set the rivet, which got old quick. I thought maybe the gun was starting to wear out or something, but it turned out to be part of the internal mechanism had started to unscrew from itself and was limiting its range of motion. We had disassembled the gun months ago to clean all the proseal out of it, and I think we must not have tightened everything back up fully. Whew! That was an easy fix, I was hoping I wasn't going to have to end up buying another gun or something. Anyway, after a night of riveting here's what we ended up with:

L baggage floor and baggage door opening, from inside

Baggage door opening, looking inside toward floors

All sealed up!

Baggage floors

We're now through Section 33-7 Step 5... yay! The second half of this section will now build on this and install a cover panel on the R side of the baggage area, and match-drill and install nutplates to hold the Baggage Bulkhead Corrugation panels.

The end of Section 33 is in sight!!!