Monday, June 24, 2013

Prepping F-1215 Fuselage Ribs

In an effort to make some progress while the color choice for the interior paint is being finalized, work began on prepping the F-1215 fuselage ribs.  Prior to deburring, the F-1215 ribs required cutting and removing a metal strip that bridged one of the openings on the ribs. A cutting wheel could have been used … but the shop has a metal nibbling tool which has seen very little use since it was purchased in the 70’s, so thought this would be the perfect tool for cutting the metal strap.
Using a nibbling tool to cut away the metal strap bridging the opening in one of the F-1215 fuselage ribs.
The W-1215 rib on left has the strap … W-1215 rib on the right has the strap removed.
After the straps were removed from all the W-1215 ribs, each rib was filed smooth and given a final smoothing with the 1” Scotch-Brite wheel.
Using the 1” Scotch-Brite wheel to smooth the edges of a W-1215 fuselage rib.
Next up are the baggage compartment ribs which hopefully will get done tomorrow.

Sunday, June 23, 2013

Work On The RV-12’s Fuselage Begins

It has been a couple of weeks since the last post … due in part to taking a few days away from the project after the fuselage inventory was completed, coupled with waiting for tools and materials as well as with dealing with a yet to be resolved interior/exterior color theme.

Just before the fuselage kit arrived, I attended an EAA pancake breakfast at the airport I had hoped would become home base for final construction and phase one flight testing of the RV-12 … only to find out the likelihood of finding a hanger (or shared hanger space) is practically zilch.  The possibility still exists for using the EAA’s facility for assembly, but after assembly there is apparently no place there to shelter the aircraft. So being just a little depressed about the situation, decided to take a few days away from the project after the inventory was completed.
Components making up the RV-12’s center section.
After studying the plans and looking more closely at finished RV-12 aircraft, it became very apparent there were a few issues which created an instant dilemma, beginning with the first piece of the fuselage puzzle … the F-1204 center section as seen in the above photo.
Primer & interior paint … basically, the shop only had a very small quantity of the Akzo epoxy primer remaining. Unfortunately, Akzo can only be purchased in 2 gallon batches (1 gal epoxy, 1 gal catalyst). I had not ordered more earlier because the under the floor pan components would only require at most a pint of primer (if that), so research was being done on finding another primer that would work well with interior paint. Ultimately, this proved to be a waste of time because builders have reported on the forums of good success using the Akzo primer with Sherwin-Williams Jet Flex water reducible (which is an interior paint made to Boeing specifications) as long as the Akzo is top coated in 24-48 hours. I really like Akzo primer so one problem solved … another batch of Akzo was ordered (there will still be a lot left over perhaps to pass onto another builder). Jet Flex interior paint is available in solvent based (which is NOT Isocyanate free (think Bhopal India disaster) and requires a fresh air respirator) and water reducible which can be sprayed using a good organic vapor filter on a respirator …  so I’m inclined to give the Jet Flex water reducible a try based on other builders good experiences with the paint.
Knowing the Akzo primer must be top coated within 24-48 hours opens up another can of worms … what color will the exterior of the airplane be? Should the interior paint color tie into the exterior color scheme? What is the exterior color scheme? Oh … what about interior upholstery appointments and seat belt color choices? Was hopeful all these decisions could be dealt with later by kicking the can further down the road for the time being (much the same as Congress does) … but as it turns out, the RV-12’s center channel assembly is visible and will require primer and interior paint.
Some builders spray the fuselage interior after assembly (but it is hard to get the paint evenly into all the nooks and crannies) and some prior to assembly. Some builders who have painted the fuselage interior after assembly have said, if done again, they would probably paint prior to assembling the parts. I’m inclined to paint prior to assembly because none of the rivets are set with a rivet gun which will mar paint. Unfortunately, parts are riveted onto the F-1204 center channel in the very first step of the plans, so a command decision is required … and soon. DOG Aviation has already received a few color chips with more on the way, along with interior samples as well.
Although not doing any assembly yet, forward progress on the fuselage has begun. The aft portion of the RV-12’s F-1204 center channel required being match drilled to the holes in the F-1204D center section aft bulkhead. Clecos are used to secure the center section and aft bulkhead onto the bottom skin for horizontal alignment and clamps are used to snug the two parts together for drilling. The match drilling consists of drilling 73 holes and after drilling, two of those holes are enlarged with a #11 drill bit. The center channel is 5/16” thick and is on a slight angle so the DOG Aviation procurement department purchased a drill guide to aid in drilling straight holes.
Drill guide with drill bit inserted.
Drill guide viewed from the bottom. The V on the bottom allows the drill guide to center a hole in round tubing as well.
Because the center channel material is so thick, if the holes are not perfectly square, the heads of the solid rivets going into the holes will not set perfectly flat. Sure a piece of hard wood with a hole in it would work, but did not have any lying around the shop and a thick chunk of it costs almost as much as a drill guide.
                                          Using the drill guide to match drill the first of 73 center section holes
                                          in the aft bulkhead … starting in the center and working out.
 Making progress slow but sure … lots of holes still left to drill using the drill guide.
                                         Completed match drilling of the F-1204 center channel to holes in F-1204D
                                         aft bulkhead - all 73 holes completed, plus two holes enlarged to #11.
After the holes were drilled in the center section, the components are disassembled for deburring. Deburring the outer portion of the center channel was a snap using the Avery deburring tool. However, that tool is too long for use inside of the center channel. At first the bit was unscrewed and spun by hand (as done before) but doing 73 holes this way … my fingers were getting sore just thinking about it! There had to be a better way. After a little brainstorming, hit upon an idea that proved to work great! The angle drill is a seldom used tool in the drawer and appeared to have the same thread size as the deburring tool bit. So simply screwed the deburring bit in and went to work easily deburring all the remaining holes in the center channel. It is always satisfying to successfully repurpose a seldom used tool with great results.
Using the angle drill to deburr the holes inside the center channel.
Admittedly, color choices and interior decorating is not my forte. So while struggling with those issues, work will continue on fuselage items that will need to be done eventually anyway, such as separating parts on the band saw, filing, deburring, smoothing edges, etc. Some parts such as the ribs under the seat and floor pans could also be primed at this time since they will not receive a top coat of interior paint.

Friday, June 7, 2013

RV-12 Fuselage Kit Inventory Completed Kudos To Van’s

Wow! Inventorying the RV-12’s fuselage kit takes a little time, but has finally been completed. As far as the sheer number of parts goes, the RV-12’s fuselage kit is by far the biggest kit thus far.  The parts count, (not including well over a thousand rivets) is over 1,350 components and that count does not include a couple of extra sub kits such as the auto pilot kit which contains mounting brackets, small amounts of hardware and rivets.

It amazes me that out of all those parts, nothing appears damaged and only three small grommets were missing from one of the paper bags. A call to Van’s to report the missing grommets revealed, by way of the date code, the bag was filled by a trainee on that day …. oh, so close to perfection. The missing grommets are on the way.

Even though there are a few grommets missing, kudos to Van’s for an amazing job of amassing and safely shipping that many parts virtually flawlessly.

Thursday, June 6, 2013

RV-12 Fuselage Kit … Parts-O-Plenty

The RV-12 fuselage kit inventory is slowly coming to fruition.  Was hoping to have the inventory completed by today, but rain throughout most of the day prevented the large shipping crate from being opened outside so the parts bundles could be accessed for inventory.

There is a lot going on with the fuselage … the amount hardware and parts reflects that. The fuselage kit contains oodles of plastic and brown paper bags chocked full with a myriad of rivets, platenuts, washers, screws, bolts, nuts, grommets, pins, fuel and brake line fittings, bearings, bushings, blocks, cotter pins, clamps, etc., which all required being counted, except the rivets.

Some builders keep the parts in the paper bags and search for the part on the master inventory list, then go to the appropriate bag for the part … all of which can work OK, but has its flaws. Often times the only way similar parts are differentiated from one another is by their quantity. So for me, the problem with keeping the parts in the bags is as they are used, the counts change and some items can quickly become hard to identify between one another.
All the small hardware in the RV-12’s fuselage kit was transferred from paper and plastic bags into 6 parts trays.

The DOG Aviation inventory control department opted to take the time to place the hardware items into parts bins and make labels identifying all the small parts.  Admittedly, it does take a little upfront time to do this … but moving forward, all similar parts are in one spot … quick and easy to find. It required four parts trays for all the hardware and another two for all the rivets.

Hopefully the inventory will be completed tomorrow if the weather cooperates.

Sunday, June 2, 2013

An Early Christmas At DOG Aviation

Don’t believe I’ve mentioned this before but I understand the shipping crates Van’s packs their aircraft components in are made by a blind carpenter. When you see how well built the crates are, you just have to scratch your head and wonder how such a well built crate could be built by a blind person … it’s amazing.

Opening the RV-12 fuselage crate seems like Christmas in June at DOG Aviation. The screws securing the lid to the crate were removed and the top was slid off reveling yet another well packed crate from Van's Aircraft.
Photo of the RV-12 fuselage shipping crate with the lid removed reveals the well packed contents with two large envelopes … the envelope with the fuselage drawings on the left and the inventory packing list on the right.

Van’s wrapping paper, being mostly white, isn’t very Christmassy looking, but that was overlooked as the filler paper was removed from the crate and the parts bundles were carefully unwrapped revealing the RV-12's  fuselage goodies. As with the previous kits, there are quite a few sub kits containing multiple pieces which are wrapped together in plastic wrap.
All of the lose parts and bundles without all the wrapping paper … skins are on the bottom under the cardboard.
Did not begin the actual inventory today, but did place the fuselage’s instructions into the plan book and paged through the plans. There is a lot going on in the fuselage and it will take some time to review the plans more to get a good feel for what and when to dimple for the flush rivets being used on the RV-12 … there is some serious homework to do.

Saturday, June 1, 2013

RV-12’s Right Flaperon Completed

This first day of the new month marked a milestone for the RV-12’s construction … the completion of the right flaperon which also signifies completion of the RV-12’s wing kit.

After the A-1202A&B aft skins were riveted onto the A-1205 ribs using the same method as on the left flaperon, a small assembly procedural change was made for the way the nose skins were riveted. After the counterbalance tube was installed on the left flaperon, theA-1201C outboard nose skin was riveted in place first, then the inboard and center skins were riveted in place. This time, since the nose skins were already match drilled, after the counterbalance tube was riveted in place on the right flaperon, the A-1201A, B &C nose skins were secured in place onto the right flaperon’s skeleton with Clecos, then riveted with flush rivets.
Securing the A-1202A skin onto the right flaperon’s skeleton with Clecos.
Using the pneumatic rivet puller to rivet the right flaperon’s aft skins in place with flush rivets.
                             As with the left flaperon, the hand rivet puller was used to set the aft most row of bottom
                              rivets which sit high at first because they touch the set rivet on the opposite side.
Right flaperon’s aft skins riveted onto the A-1205 ribs with flush rivets.
Riveting the counterbalance tube onto the right skeleton’s outboard nose ribs with a LP4-3 pop rivets.
Placing Clecos into the A-1201C nose skin to secure it onto the right flaperon’s skeleton.
All three nose skins attached to the right flaperon skeleton with Clecos and ready for riveting.
Using the pneumatic rivet puller to rivet the nose skins in place with flush rivets ... almost finished.
Setting the last flush rivet in the right flaperon with the pneumatic rivet puller.
After completing the riveting of the skins, the last thing the instructions call for is to install two pivot bearings on each flaperon using Loctite 243 on the first third of the threads. The plans instruct the builder to screw the pivot bearings into the pivot brackets until the center of the bearing hole is 11/32" above the flaperon skin. Because the bearing wants to flop around, measuring can be tough … one tip on the forums was to place a long AN3 bolt (which is 3/16” diameter) through the bearing and then measure ¼" from the bottom of the bolt to the flaperon skin … which would be the 11/32" minus 3/32" (half the thickness of the bolt) or ¼".
That procedure was utilized and improved upon by cutting two small pieces of ¼" OD tubing to use as a visual reference. The pivot bearing was screwed in until the bolt touched both pieces of tubing evenly. Then a square was used to true up the bearing.
                                         Using two pieces of ¼" OD tubing and a long AN3 bolt to achieve a
                                         clearance of 11/32" from center of the pivot bearing to the flaperon skin.
Completed left and right RV-12 flaperons riveted with flush rivets.