Baggage Door

Got the baggage door strut installed tonight! After measuring open and closed distances, I fabricated some mounting brackets, riveted the inside door skin into place, drilled a couple holes and installed some #8 machine screws purchased in the "aviation aisle" of the local home supply store. The resulting setup looked like this:

Baggage door strut laid into position (mockup, not fastened yet)

Closed eye-to-eye distance of 5.5"

Open eye-to-eye distance 9-1/8"

The geometry came out great! To attach the strut on the airplane side, I ran a 2" long #8 machine screw down through the F-1034B/F Seat Back Braces and cut some leftover aluminum tubing to use as a spacer between the two halves. You can kind of see it in the first photo above. After temporarily installing some washers and nuts, I was able to verify the proper movement and latching of the door, which seemed to operate perfectly!

There's just one problem.

Whoever posted in the forums that they used (and recommended) a *20-lb* force gas spring is either considerably stronger than I am, or completely insane. 20 pounds doesn't seem like a heck of a lot, but rigged up in this manner, it is WAY too strong. When you pop the latch, the baggage door jumps open and basically punches you straight in the gut if you're not ready for it. If only I had the camera rolling the first time I opened the door, all proud of my work.

So, I'll be ordering a different strut from McMaster with a 5-lb force rating (#9417K6) as well as returning the bracket that I had originally ordered. The bracket was a good idea, but being relatively large and made of steel, it was way too big and bulky to really use on the baggage door. It was much easier (and cheaper) to make my own bracket out of aluminum angle.

Last order of business for the baggage door: Fit a micro-switch to the F-1031 Baggage Door Seal Channel. Hopefully we'll be able to knock that out this weekend, and finally get around to painting the interior too!

Baggage Door - EAA Tech Counselor Visit #3

One step closer to finishing the baggage door! Tonight I fabricated and installed a stiffening plate across the baggage door frame where I had cut it to fit the latch. I'm pleased to say it added the exact stiffness I was hoping it would, and now the only thing left to do is find and install a mini strut to hold the door open and prevent it from opening too far.

The stiffening plate connecting the two halves of the baggage door

As for the strut, I believe I've found the correct part for that from McMaster-Carr, P/N 9417K6, a "Miniature Gas Spring" with travel from 5.55" - 9.05" and 20lb force (edit- see later post here, recommend 5lb force instead), combined with P/N 9417K92, the accompanying mount bracket (edit- this bracket is too big and bulky, just make your own out of aluminum angle). The parts are on their way, and I'm hoping they work out nicely. After that is installed, we're just a few blind rivets away from calling the baggage door 100% complete!

In other news, our EAA Tech Counselor came by tonight for a visit to see the project. This is technically his third time here in the shop, but the first time was before we even set our first rivet on the empennage kit, just to look over our shop and tools, and to make sure we were on the right track. The second visit was after we had completed the elevators but hadn't yet started on the tailcone. Unfortunately, during those previous visits we never completed any official EAA paperwork to document the inspections (other than logging it ourselves). No big deal but in hindsight it would have been nice to have done it just to cross t's and dot i's. This time, though, we got our yellow slip:

EAA Tech Counselor Notes

He did an extremely thorough job inspecting the wings and fuselage, and I'm happy to say that overall he had some very positive feedback for us. He even noted "excellent workmanship overall" in the comments.... wahoo! Talk about how to brighten someone's day. It felt incredibly rewarding to have an expert in E-AB aircraft (and an RV-6 builder/owner himself) look over our work and give it the thumbs-up. The only thing he noticed was on the aileron torque tubes, the nuts holding the tubes to the bearings didn't have enough thread showing. The FAA rule is that there must be at least 2 threads showing beyond the nut, and on our wings that didn't work out to be the case:

The aileron torque tubes with AN365 locknut and washer, and only ~1 thread sticking out the top

I was already aware of the "2-thread" rule, but admittedly I guess I thought it was more of a guideline and not a hard-fast rule. Also, I thought I had the hardware installed per the plans, so "it must be right." Plus, the way the whole tube is in there, there's no way it's coming out even if the nut were to fall of entirely somehow. So at first it seemed like kind of a trivial finding, but since it's an FAA rule and will surely be looked at by the DAR when they come to inspect the plane for airworthiness, this could end up costing us a fair amount of time (likely several weeks) if they ding us for it and make us fix it, then we'd have to perform the fix and reschedule a time for another inspection. Way better to remedy this now!

So how did this happen in the first place? Well, we got out the plans for the wing and turned to Section 23 (aileron actuation) and reviewed the hardware callouts. Guess what? We goofed. They call for an AN364 (which is a low-profile version of the more common AN365) locknut to be installed in this location... oops!

The hardware callouts in the plans, Section 23-7, Figure 1

Simple oversight on my part in the callouts. Definitely a good catch, and lesson learned! I'll have to dig up the correct hardware (couldn't find any AN364 nuts in my hardware bins) and swap them into place, should be a very straightforward fix.

Other than that one finding, everything else went very well during the inspection! We then spent a long time discussing all kinds of things from avionics to flight characteristics, and all the different aircraft he's seen over the years. I can't possibly stress how thankful I am that a program like EAA's Tech Counselor program exists, and even more so for the individual counselors who volunteer their time to help others like us get through their build in a correct and safe manner. Thanks Tom! :-)

Baggage Door

Happy Labor Day! Well, this turned out to be an "interesting" 3-day holiday weekend for us. We went to Des Moines to attend our friends' wedding, but unfortunately we got our dates mixed up (100% my fault) and thought the wedding was on Saturday instead of Sunday. It turned out that there was also a different wedding taking place at the same time and location on Saturday, which we of course ended up at, all dressed up and ready for a fun night. It slowly dawned on us that we were in the wrong place when we didn't recognize anyone in attendance, including the bride and the groom once they appeared. Sometimes an epic fail makes for a great story!

Mike and Sarah at the wrong wedding... Thanks to the groomsman who took this photo!

So by the time we stayed another night in Des Moines to attend the correct wedding, we really didn't get much time to build over this long weekend. That's ok though! We did get some time to continue with the baggage door and take some more pictures of the custom latch assembly though:

Cutout is 1" x 3-3/8", starting 1/2" forward of the aft edge of the door and vertically centered on the existing hole punched for the key lock. The cutout will go through two rivet holes in the door leaving two small notches in the cutout, but they will be covered by the latch when it's installed.

A 1/8" thick steel plate 3" x 5" was fabricated to strengthen this area of the door. The cutout at the bottom is made to clear the baggage door frame.

The latch installed into the hole and screwed into place

The baggage door with latch installed

The inside baggage door cover with modified  cutout, measuring 3-1/4" x 1-1/2". A new #30 hole was drilled to mate with the frame, which must be cut to allow clearance for the latch.

The door riveted together and installed in the plane

The latch holding on to the F-1031 Upper Baggage Door Seal (the bolt is temporarily wrapped in electrical tape until I get a rubber stopper for it)

Closeup of the latch and frame cutout

The open baggage door, inside cover isn't riveted on yet

A video of the door in operation

It works great!! I still need to figure out two more things with the door before it's done: (1) The frame needs stiffening in the area where I cut it so that it won't have a tendency to bow. It's not bad as-is but I want it to be a little better. I should be able to rivet a piece of 0.032" aluminum between the two halves and that should easily take care of it though. (2) Before riveting on the inside cover, I want to source and install a small strut to facilitate the opening and closing of the door, as well as limit its travel. In addition, I'll need to finish up the F-1031 channel and install provisions for a microswitch and striker plate. Again, shouldn't be too big of a deal.

That's pretty much it for now! I'll be on travel the rest of this week, so there probably won't be much more progress until this coming weekend... until next time!

Baggage Door

As stated in an earlier post, I held off on completing the baggage door section while I searched for a latch mechanism that I could install and have a little bit more advanced open/close function than the standard lock-arm provides. Well, good news! I have found and settled on a latch: The Southco model C2-33-21.

Southco C2-33-21

This latch works by pushing in where the key lock is, and then the rest of the lever "pops" out. There's actually a video I found of its operation here on youtube: https://www.youtube.com/watch?v=h2d2S5Rcqgg. One downside is that the key for this will be different than the one for the door locks and ignition, but I think that should be ok. To close, the arm has an adjustable bolt that will catch on the back side of the F-1031 Upper Baggage Door Seal and hold the door shut tight. I'll probably have to install some kind of striker plate for that (maybe even with a microswitch) so that it's not just holding on to the aluminum. Shouldn't be too hard.

Well, I got the latch in the mail yesterday and so it's time to get to work on it. Unfortunately I don't have any pictures of the process yet (I will soon, I promise) but it's going really well so far! I was able to hang the door and get everything aligned and the hinges drilled. I'm really happy with the alignment of the door. It was a process that took a little longer than I imagined it would, and it was really quite tedious to get it to sit just perfectly centered and square in the opening, but Sarah and I prevailed. I feel like part of our success was due only to luck, but I'm not going to complain about that. Once the door was hung, I then made the rectangular cutout for the latch in the door skin and also cut a steel reinforcement plate to go behind the outer skin and provide extra support. The latch fits in place and catches on the F-1031 perfectly! I really like the geometry of it, and once I get everything finalized I'll take a bunch of pics and provide measurements, etc.

In the procurement department, big things are happening too! We ordered our stick grips from Tosten; our fuel filters, check valves and Walbro pump are on the way; ordered some 2 AWG welding cable, ring terminals, and hydraulic crimping tool from Temco; got some Amphenol 31-326-RFX BNC connectors and Harbour RG400 cable; and finally bought the necessary 5052-O tubing and a number of AN fittings from Aircraft Spruce to be able to start fabricating the fuel and brake lines. I've been talking with the folks at DJM about a console throttle quadrant for the RV-10, and I've also been talking with Paul Grimstad about the Control Approach rudder pedal system. He's working on a new design and it's taking a bit longer than I think he originally anticipated, but the good news is he is "back in business" making pedals so however long it takes it will be worth the wait! He's been great about getting back to my many pestering emails and providing updates, photos, etc. I'm confident this will NOT be a P-200 mag situation ;-)

I've also been pondering what to delete/add to my finish kit order. I've looked through a number of build blogs about this and have settled on doing pretty much the same thing Ed Kranz/Justin Twilbeck did for their finish kits as far as deleting wheels/tires/axles to upgrade to the Matco/Desser products, and a few other tidbits. Justin's delete list can be found here. I'm also going to be deleting the windows because I'll be using the Cee Bailey ones. I really hope that upgrade is worth it, I haven't bought them yet but since I've already deleted the fuse windows I'm kinda stuck with that decision now. I'm sure it will be fine.

Well, that's pretty much it for now. Hopefully for my next installment I'll get some photos up of the baggage door!

Upper Forward Fuse - Baggage Area

Yesterday I had a brief session in the factory to remake the F-1044B angle that I had mis-drilled last time. I actually ended up doing this twice, because I messed up my first remake. Third try was the charm though, and so now in addition to the usable part I have two 17-5/16" long pieces of aluminum angle that I'm 100% certain will get put to good use on some future part of the plans. Not ideal, but oh well that's the way it goes sometimes. At least I didn't have to reorder any parts I suppose.

One other bit of news from yesterday, I called Van's to place my order for the finish kit! They are quoting an 8-week lead time, and although I'm pretty sure I won't be *done* with the fuselage in 8 weeks, it will be nice to have some of the parts contained in that kit a little ahead of time. I have a few weeks now to finalize a "delete" list and send in to them. I'll cover this in a future post.

In the meantime though, tonight it was time to start on the task of deburring all the upper forward fuse parts. It actually went pretty quick using the EZ-Burrs on all the drilled holes and the belt sander for all corners and edges. I started dimpling a few of the smaller parts, but got bored of it and started thinking about how I won't really be able to get too much further with all these parts until I figure out my panel layout a little better. So, I tossed the pile of parts back into the shelf and will continue with that as we get closer to section 41 where it all actually has to be attached permanently (Section 31 is sort of designed to be an "at your own pace" section and allows you to slowly put your panel together outside of the airframe and then attach the whole works in section 41).

Shifting gears to Section 33 then (remember 32 is tailcone attach, complete!), we began work on the rear seat and baggage floor areas. I won't be able to final-install the floors yet before we get the steps back from powdercoating and I finalize my antenna layout, putting any necessary doublers under the back seats... but that won't stop us from prepping all the parts!

Derek came over tonight to help out, and we had a mega-productive session match- and final- drilling the floor covers. We started off with the back seat floors and moved aft to the baggage floors per the plans, which included cutting some AN257-P3 hinges to size and match-drilling them to the panels. The hinges will be used to attach the rear seatbacks to the airplane, and allow for removal by simply pulling the pins out. I took charge of the L side of the airplane, and Derek took the R side (Sarah took a "supervisory" role tonight). With two drills and two cleco pliers going, we made quick work of it all!

The back seat floor covers after match-drilling

The L baggage floor cover with hinge clecoed into place

Derek match-drilling the hinge to the R baggage floor cover

We finished the night off by making the F-1022 B-G stiffeners and final-drilling them to the R and L baggage floor skins. Derek did an awesome job cutting all 12 pieces from the two provided long aluminum angles using the bandsaw and belt sander to clean them up! While he was doing that, I went ahead and deburred all #30 holes in the four floor panels, leaving only the #40 and #19 holes to finish up.

Great night of productivity! It really feels like things are kicking into high gear, and I can't wait for this thing to be ready to fly!! Gotta keep my excitement in check though, still got quite a ways to go... it's hard to imagine that we're really only about halfway done at this point... probably not even half!

Tailcone Attach - Cradle - Upper Fwd Fuse - Section 32 Complete!

Today was one of those "builder's dream" productivity days! It actually started last night when I finished a few of the rivets that I could reach myself for the tailcone attach. I was actually able to reach almost all of the rivets on both sides and that attach the ribs and bulkheads, but still needed Sarah's help to finish the ones along the bottom. While I waited for that, I figured it was time to get the fuselage off of my work tables and set it on the ground in its own cradle. I set out to build those, and what I ended up with is pretty close to other ones I've seen online:

She's on her own feet for the first time! (albeit with temporary shoes... err maybe wooden clogs)

Presenting the RV-10 taildragger!

The front legs are basically just 16" long 2x6's with holes match-drilled for one big and one small hole in the center section bulkhead. Basically working from inboard to outboard, the holes go "SBBS": I have one small and one big wing attach bolt in positions #1 and #3, and then these 2x6's are attached at positions #2 and #4. I had to scoop out little reliefs on the inside faces of the 2x6's to make room for the  wing attach bolt heads, which took a bit of time and head-scratching, but I eventually prevailed using a bit I had laying around from when I made my computer desk in the drill press: the kind of bit you use to install recessed hinges in cabinet doors.

Hardware-wise, I used 4x 1/2" x 8" bolts in the "big" holes and 4x 5/16" x 8" bolts in the "small" holes. I had originally bought 3/8" bolts for the small holes, but silly me, they were too big. In the photos above, I hadn't yet made the exchange so you only see the big bolts in place.

For the tail wheel, I padded some 2x6's to hug the end of the tailcone, and ran a single 3/8" bolt up into the tie down hole, tightened only to be "snug". It worked but it wasn't super stable if you put a lot of weight in the tail, so I ended up rigging a little 2x4 arm to come forward and rest against the bottom skin a foot or two ahead of the attach point. The arm is held tight against the bottom skin with a tiedown strap. A little ghetto but hey it works. And there you have it!

At about this time, Sarah came out and we finished riveting the bottom rivets between the tailcone and fuselage. That puts an end to Section 32... yay! I'm liking these few-day-long sections as opposed to the few-week-long sections like 29. :-)

Next on the agenda was the Upper Forward Fuse assembly, Section 31. This section is relatively straightforward and starts off like many of the other sections fabricating some small aluminum pieces for who-knows-what and then as you start to cleco things together it all starts to make sense. I snapped a photo of the first step:

The F-1044C Spacer - And my feet.

Interestingly, this piece that I fabricated played a co-starring role in a minor goof-up I had today. As you begin to assemble the different pieces, there was one kind of odd thing they have you do, which is to match-drill the F-1044B angle into a brace on the firewall by drilling "up" through the firewall recess (they first have you drill a pilot hole "down" from the brace through the recess). Kind of an interesting process. Anyway, the goof-up was that I forgot to put the F-1044C spacer that I had just so proudly fabricated into place, so the hole drilled through the F-1044B angle isn't in the correct location. Oops! I'll have to toss the piece and make another one. Oh well, should be a zero-sum game in the end, I have plenty of extra aluminum angle sitting around. For now, I decided to continue with assembling the rest of the assembly for match- and final- drilling:

The "subpanel" and three ribs clecoed to the forward fuselage. The errant F-1044B angle (accidentally sans F-1044C spacer) is visible attached to the middle rib.

For a while, I thought this F-1044A center rib might have been formed incorrectly at the factory-- the holes in the forward flange are much closer to the web than normal and were a PITA to dimple. They are correct though!

Right side of subpanel

Forward top skin clecoed into place for final-drilling!

This makes the airplane instantly look super-neat (as if it's not already super neat-looking, anyway). It's easy to get lost just staring at the thing and watching the time go by. However, I resisted that temptation and proceeded with all the necessary drilling tasks. The focus then shifted to the inside of the cockpit now, where the last drilling task remained: match-drilling the F-1003D/E flanges. These pieces start life as 0.032" aluminum angles and must be fluted to match the contour of the top skin, ensuring that no flutes are made where the instrument panel attach holes are. This proved a bit tricky but in the end wasn't all that bad. After that though, you have to hold the pieces up under the panel and match-drill down (towards your fingers!) into the angle. It was a bit of a sticky situation but ultimately I only had one "close encounter" with a drill bit poking through, and no blood was shed during that battle. Whew!

That's pretty much it for tonight! Tomorrow I think I'll start on an idea I have for a center console to go between the panel and tunnel... stay tuned!

Tailcone Attach - Static Ports

The tailcone attach section is going a lot more quickly than I thought it would! Finished final- and match-drilling the various parts between the fuselage and tail section, and before long the two halves were separated again for deburring, dimpling and countersinking. There were a small handful of parts that needed priming, including some parts around the baggage door, both mid fuse longerons (I had previously left them only clecoed into place until this section could be completed) and the F-1006 bulkhead parts which I didn't prime or rivet together during the empennage construction to simplify things a bit.

While the primer was drying, I wanted to finish one relatively small task that would be much easier to complete now before the tail gets attached-- installing the static ports. I've decided to go with the SafeAir static ports and plumbing lines, which I've had on hand for some time now but haven't done anything with. Looking through the instructions, installing the ports appeared to be a lot easier than I was thinking it was going to be. You have to enlarge the small pilot hole in the tailcone side skins to 1/4" in diameter and then mount the static ports from behind. The port, with its angle attachment and adapter for air hose, looks like this:

SafeAir static port with 90-degree air hose fitting

(photo stolen from online, I forgot to snap a picture of mine prior to installation)

To actually mount the port, you have a few options. Many builders choose to rivet the ports into place, which would be fine except I'm not a huge fan of dimpling the middle of a large piece of skin once it's already been installed. It can be done, but it's time-consuming, nerve-wracking, and never seems to produce the same quality dimples you can do on the bench. The second option is to adhere the part from the back with proseal or some other adhesive. I chose this route and actually just used standard epoxy resin to install these.

I first traced a circle on the inside of the skin to mark where the port will actually mount, and then removed the primer on the skin from this area using a dremel with wire wheel brush. Cleaned the area up a bit with some acetone (carefully!) and then scuffed up the face of the port with some sandpaper, making certain to not scuff up the actual "nipple" on the port itself. Cleaned both surfaces again, this time with alcohol, let it dry quickly and applied the epoxy to the static ports, again making sure to keep it away from the nipple. Then I stuck them into place and held firm with some masking tape. Hopping out of the cone to the outside, I then cleaned up any excess adhesive with alcohol. After the epoxy cured, I installed a tee fitting into an existing hole in the bulkhead and ran the air lines to it. The result came out pretty good!

The static air port after installation

Inside view of static system ports and air lines... ready to run to my ADAHRS!

Once this was done, I riveted the Mid-Fuse longerons into place which was maybe a couple dozen rivets per side and didn't take too terribly long. Then the "momentous moment" was upon us: mate the fuselage and tailcone for good!

The last time we see the tailcone by itself

Riveted the F-1006 bulkhead to the tailcone (this is the opposite from the previous time they were joined, where you cleco this bulkhead to the fuselage)

Final moments before joining

Joined!

Now, just a few dozen (ok, maybe a hundred or so) rivets and this thing is permanently attached... nice!!! That's it for now, I'll save the fun and rewarding task of riveting for another day...

Tailcone Attach

As mentioned in an earlier post, we are reordering events slightly here and performing Section 32 (Tailcone Attach) prior to Section 31 (Upper Forward Fuse).

So tonight we had one of those few moments that really didn't take too much work but really had a tremendously rewarding payoff. It's amazing how seeing what the airplane looks like from firewall to tail can really light a fire under you!

Started Section 32 with a relatively naive mind, in the sense that I hadn't really done much read-ahead in this section and I just planned to perform each step as it is called out. The section starts with the F-1006B Bulkhead, final-drilling and dimpling a number of holes (not sure why this couldn't just have been done in the tailcone section for the empennage, but whatevs), and then transferring the bulkhead over to the fuselage and clecoing it to the baggage floor ribs. The very next step is pretty cool: cleco the tailcone to the fuselage.

Tailcone clecoed to fuselage, R side

Tailcone clecoed to fuselage, L side

There are a LOT of rivets from front to back!

F-1074 Tailcone Forward Top Skin clecoed into position

Holy mackerel, this airplane is big!

I'd like to point out that Sarah and I have seen dozens upon dozens of RV-10's before, but always in their "natural environment" like a hangar or ramp somewhere, or of course Oshkosh. We're also intimately familiar with the size and shape of both the fuselage section and the tailcone section from building one of each. Furthermore, we've had those two pieces laying on benches next to each other for the past couple days now and could easily picture them mated together. Even so, none of that actually prepared us for the emotion that was felt when we took a step back to admire the two sections actually clamped together, temporarily forming a complete fuselage from firewall to tail!

To be honest, the fuselage section always looked a bit small to me as we were building it. I'm aware of how much room there actually is in a complete RV-10 since we've sat (and flown) in a few of them, but for whatever reason the fuselage up until this point has always appeared kind of small to us. Now all of a sudden with the tailcone attached this airplane looks HUGE! We spent a good 30 minutes just staring at the fuselage and marveling about how this is going to be the machine that takes us (and plenty of our stuff) all over the place in just a couple more years. It's times like this that make up for all the tedious and sometimes boring work that you can drone on with for sometimes weeks at a time.

Anyway, once the shock had worn off and the drool was wiped from our mouths, we finished up the build session by match-drilling the four holes per side between the mid fuse and aft longerons, and installed bolts to hold things in place. Two little shims were fabricated out of 0.025" scrap (about 3/4" x 2" in size) to tuck between the top skin and the mid fuse longeron. Next step is to match-drill the side skins to the longerons, but that's enough for tonight... more to come soon!

Fuse Side Skins - Steps - Section 29/30 Complete!

Let me start off by saying I'm just oh-so-happy to be done with Section 29... it was one of the less-fun and time-consuming chapters of this build so far. It contained 22 pages of tasks, many of which required fabricating special tools and/or forming giant (and expensive) pieces of aluminum angle or aluminum sheet. On top of that, there were a gazillion holes that needed to be drilled, deburred, countersunk, and/or dimpled. But enough of me complaining, really it was actually quite rewarding work, even if a lot of it was a PITA.

Started off this morning installing the couple hundred or so blind rivets that hold the forward floor panels into their permanent locations. This then allowed for the next step of installing the landing gear mounts:

The landing gear mounts after final installation

Close-up of L landing gear mount

A note about installing these: It takes waay longer than I thought it would to get all the bolts, washers, and nuts into place and torqued properly. I thought "eh, it's just a handfult of bolts, how hard can it be?" Trust me, it takes time. One of the more interesting parts of this is figuring out how to get the washers onto the bolts along the bottom row... the gap between the center section bulkheads is way too narrow to get your hand inside, so I used a super-long set of needle nose pliers to carefully hold the washer and put it over the bolt threads. I also used a magnetic pickup tool to grab the washers any time they got accidentally dropped, which inevitably happened a few times. In the end, patience prevailed and they are all in!

With the gear mounts installed, I put and end to Section 29 in about 5 more minutes, after riveting the F-1088-L/R fuselage ribs into place now that the floors are done. Whew!

Turning the page to Section 30 now, I picked up where I left off with the steps. The baggage floor needs to be half-installed with clecoes to hold proper alignment, and then the plastic blocks need to be match-drilled to the baggage ribs. There isn't a whole lot of room here to do all that:

The L step, with baggage floor peeled up and clamped to the upper back seat brace to gain access

In the photo above, you have to drill sideways through the plastic block on the right. So, I got out the right angle attachments and #12 bit and put together this contraption:

Right-angle drill for step mount

I made two holes on each side using this technique, and then removed everything else to gain easy access and make the final two holes. It really wasn't all that bad, and only took maybe 10 minutes. After that, the steps were re-inserted and "clocked" to the right position, which should be 45-1/4" back from the aft edge of the center section bulkhead:

Clocking the steps (measuring tape is clipped over a piece of scrap angle iron that is clamped to and coming down off the aft side of the center section bulkhead)

A couple match-drills later, holy crap we're done! I think the whole section took maybe an hour... wow! When compared to the last section, it feels pretty good! Of course, I'll still need to prime/paint/powdercoat the steps, but that will be sometime in the future.

Other than that, it's time to move on to a new section. I'm going to skip Section 31 for now (upper forward fuse/inst panel) and instead begin with Section 32 -Tailcone Attach. The main reasons for this are that I want to finish a few loose ends on the tailcone (battery tray, ELT mount, magnetic sensor mount) finished up, get them joined, and then install the casters I have to make the fuselage a "temporary taildragger" of sorts. I think that will free up the most room in the shop, and also will put us in a good position to finish up the rest of the fuselage.

So, Sarah and I went up to the front of the garage and brought the tailcone down from its resting spot on the ceiling. It was cool to set it behind the rest of the fuselage and see how it will all fit together! Sorry, no pics of that yet (it was dusty, haha). I did, however, get a jump start on fabricating the battery tray. I have an idea that I will be exploring on that front... another day!

Fuse Side Skins - Steps

Getting ever closer to finishing Section 29! Had the day off from work yesterday for my birthday (woo!) but didn't really work on the plane itself; instead I just cleaned up and organized around the shop a bit. Today, though, it's on. I started by finishing the rear air vents that Sarah had started the other day:

The L/R Rear Vent assemblies

Pretty straightforward part of the plans, just some match-drilling, deburring, and edge-finishing. I used a dremel with a small bit to smooth the inside groove of the track, shown here:

Smoothing (and slightly enlarging) the groove to smoothly fit the shaft of a AN525-10R7 screw, shown to the left.

After a quick shot of primer, they got riveted together and then put into place in the side skins, and that checks one more thing off the list that needs to be done for this chapter! Looking ahead, I needed to wait for Sarah to get home later so we could finish that one last forward fuse channel before continuing with the forward floors. So, why not skip ahead and start on mounting the steps in Section 30? I hear it's a pretty easy section, especially after the arduous and infamous Section 29. So, I grabbed the two plastic blocks used to secure the end of the step mounts and marked as shown in the plans with a silver sharpie:

Marked 3/8" from each side in the four corners for drilling

Drilled the two blocks #10 at each of the four corners

Next step was to deburr the steps themselves. I used the scotch brite wheel quite liberally around where the welds are to try and clean them up a bit... they were fairly rough-looking. A test-fit into the fuselage seemed to work well going through the main steel support bracket and into the newly-drilled plastic mounting blocks. The next thing to do is match-drill the four holes from the blocks into the baggage floor ribs, but I'll save that for later. Sarah got back home at this point and we went right into riveting the R lower forward fuse channel. This completes all the rivets for the forward side skins!

Now that the skin riveting is done, the next step will be to install the forward floor covers. This part has me a bit anxious, because the design of the RV10 is such that the forward floor covers are a permanent part of the structure-- they have to go in underneath the landing gear mounts and will basically "never" come back off again without some major work. Combined with that, there is a lot of discussion (almost as much as there is for different kinds of primers) about insulation: which one is best for soundproofing, thermal insulation, fire retardant, etc etc. You can spend months researching all this stuff and still not be happy with your decision, I believe. The biggest concern, of course, is using insulation that will not readily burn, and will not release loads of toxic smoke when exposed to flame.  I've read through all the forums, and had some good conversations at OSH with a number of builders who are very well versed on this topic, and I believe I have made an informed decision. Here's what I ended up doing.

A month or so ago I purchased a 120ft roll of 1/8" x 24" FiberFrax felt, which is a 2000deg ceramic insulation blanket and is commonly used on firewalls and other high-temperature fire-prone areas. I will be using a layer of this against the bottom skin, topped by some household-type acoustic/thermal insulation. The stuff is actually made out of recycled denim, which at first seemed a bit odd and made me a bit hesitant to use it but the more I read about it and the more I tested it (see below) the more I decided this was the right stuff for me. I also recently watched this video on the burn characteristics of different kinds of insulation:

After watching this video (although they didn't test the denim insulation in question) it kind of shot down my thoughts of using fiberglass insulation... it just melts away into a big hole! I wondered what the denim stuff would do, and I was quite happy with the results. I performed a similar test to what the guy did in the video above at 2:20.

Click here to watch the video

Mapp torch/penny burn test for UltraTouch Denim Insulation

As you can see, the insulation does carry a small flame for a few seconds after the torch is removed (slightly worse than the cellulose in the video above), but more importantly there is very little fume and it forms the same kind of char that helps to block the fire from spreading as quickly. Plus, this was at penny-melting temperatures when exposed to a direct torch flame... by the time this were to happen in the airplane it would have already burned through the firewall and a layer of fiberfrax. I hate to imagine that kind of scenario, but hey, anything is possible and you have to plan for it in your design. So, the insulation got cut and laid into place:

Layers of Fiberfrax (right) topped with UltraTouch acoustic/thermal insulation (left)

Once the insulation was laid up, I said one last goodbye to the forward floor area and clecoed the floor panels into place! That's it for tonight, first thing tomorrow I'll rivet these floor panels down and continue with finishing Section 29!