Finishing the Cabin

Status: Plodding on..

(April 2006) The cabin of the quickbuild fuse has a number of structures temporarily pop-riveted in place, including a very thick piece of angle attached to the bulkhead behind the seats which needs to be removed for slider canopies. The only way to get in there was with the Avery angle drill (image 1) which worked a treat (the first time I had to use it).The angle is saved with the rest of the "useful scrap" I am accumulating.

(Early May 2006) There are two thick aluminium gussets which attach the central main spar to the lower longerons on each side (images 2 and 3). They take the large 7/16" and 1/4" wing attach bolts, and are bolted to the fuse via the lower longerons. Longeron/skin holes were match drilled and 5 AN 3 bolts inserted with nylock nuts om each sie. Then the missing rear uppoer fuselage skin was found and the blue plastic removed (this took three hours!). This has been located in place with a central forward triangular gusset. it was matchdrilled to #40 3/32 rivet size, but is yet to be dimpled and finished (image 4). The rear baggage compartment floors were removed and match-drilled to take 3/32 rivets retaining nutplates and 1/8 pop-rivets attaching to the floor stiffeners. While I had them out I tried paining them with a spray-pack enamel - it came out an ulgy metallic silver (not obvious from the cap). i need to find a better paint for the interior surfaces.

21st May 2006 - Sunday night, and nothing worth watching on TV, so out to the shed. My back is killing me with all the leaning over into the cabin, but I managed to install all nutplates in and around the baggage floor areas. These are simple and straightforward, and all can be done with the red-handled rivet squeezer shown in image 6 below. I still need to pop-rivet these floors to the underlying stiffeners, but that will be "too easy".

23rd-25th May 2006 - Busy with other stuff, so only 2-4 hours a day to work on the plane. Baggage floors were pop-riveted in place with platenuts installed for tunnel cover plate screws. Upper fuse skin behind canopy (F-7112) was drilled, chamfered and dimpled (that took a while). Gussets and longitudinal stiffeners for F-7112 also dimpled. Rear cabin baggage bulkhead skins fitted successfully. Round channels stiffening F-7112 forward edge fitted, drilled and dimpled. Autopilot servos for pitch and roll were properly safety-wired to their mounting plates. Drawings for forward fuse seat floors, tunnel and flap motor enclosure studied. Began to fabricate aluminium tunnul cover supports for space between seats (image 8 below).

Angle drill

Fuse gusset - temp wing-attach drift pins in place

Bolted in place

Rear fuse upper skin, item F-7112

Baggage floor

Installing platenuts

Platenuts installed

Tunnel cover supports

25th May - 3rd June 2006 - Still busy with other stuff. Occassional opportunities to work on the cabin area. The "tunnel" is about 8 cm square and it lies between the seat and baggage floor ribs in the cabin floor. This tunnel carries the first elevator control push-rod, as well as wiring looms for rear-mounted structures such as the strobe control, tail-light and perhaps radio arials (not sure yet where to mount them). The images below show how a small inverted-U shaped cover is fabricated from aluminium extruded Z-section. This is riveted together once the cover plate position has been ascertained by aligning parts in situ. There is also a flat cover over the same tunnel in the baggage compartment area. All these structures are screwed to the floor, thanks to the nutplates riveted there previously. There are also two large sheet covers which need to be fitted to the forward face of the main spar bulhead seen located very roughtly in image 4 below. Images 5-8 show the components provided by Tru-Track to provide pitch control for their autopilot. Note safety wire in image 5 - absolutely necessary where no nylock or platenuts provide frictional resistance to unscrewing. Image 7show the elevator bellcrank in position, and image 8 shows it with the servo and mount sitting 2.8" aft of the bellcrank pivot point. This is the dimension called out by the intallation guide. In order to mount the servo I will need to drill out 4 of the rivets holding a piece of angle to the keel rib of the lower fuse. I will use these holes to match-drill holes in the servo mount, and then re-rivet the mount to the rib and angle. The lower flange of the mount will be drilled and flush-riveted to the lower fuse skin.

seat floors and tunnel cover

baggage tunnel cover

forward seat floors and tunnel cover

forward covers

pitch servo mount drawing

pitch servo mount safety wired

elevator push-rod bellcrank

servo placed in position note 2.8"

(7-8th June 2006) I worked feverishly over this week to complete the cabin work involving covers. These are sheet components which isolate wiring, fuel and brake hydraulic tubing from the pilots. They are held in place by screws anchored to platenuts. they cover the elevator control push rod tunnel, the area foreward of the main spar, and the central area of the forward cabin. I decided to use a standard etch primer and enamel to finish these components, saving on time and mess making up the Sterling 2-part primer. the first image shows the rear uppr fuse skin, drilled, dimpled and primed. the second image is Van' drawing of the main spar forward covers and their supports. The outboard edge of these covers is supported by a small piece of angle which is pop-riveted to the "gear attach web" which parallels the skin outside this spar. The third image shows the central forward cover, primed and painted. You can disassemble the covers because they are held together by screws and platenuts (image 4). Images 5,6, and 7 show how you have to position a small piece of angle to support the outboard edge of the forward main spar covers. this worries me - I need to drill holes in the "gear attach web" without piercing the skin which lies about 1/8" outside this web. Ken Scott at Vans says it is possible, so i wil try with my trusty drill-stop. The final image shows the forward covers all screwed together and in position.

priming fuse skin

forward covers

forward central cover

platenuts

"gear attach web"

plate support bracket

bracket taped in position

covers in position

Once completed, the forward covers are anchored to the floor skin stiffeners by screws and platenuts. Image 1 shows 1/8" guide holes drilled and clecoed. Platenuts were installed in the cover flange, and the stiffener holes were increased in diameter to allow the screws to mate easily. I bought two of Van's "tie-down" units for the rear baggage area. It will not be difficult to install thme, even though the rear baggage floor panels have been riveted in place! They consist of a couple of anodised round aluminium units. One is riveted to the floor (I think, no instructions), and the other has a tie-down ring which slides neatly in place into the former unit. So you can remove the rings if necessary. I also bought two of Vans cast iron wing tie-downs (same pic). My thinking is to carry these in the plane and screw them in place if necessary to tie down in the open. No sense in intalling these drag-creators unnecessarily!

(29th June 2006) I have been busy with non-RV work, and try to put in a couple of hours each night. Tonight Idecided to get those pesky outboard front little cover support angles finished and installed. To do this you need to drill four AN4 sized holes in the "gear-attach web (GAW)" (see images above) without going through the web into the outer skin.These holes are for LP-4-3 pop-rivets which attach the angle to the web. The drill-stop is useful for these situations, allowing you to drill a hole of limited depth through the web and missing the skin. Anyway, Iinstalled the covers, slid the angles into place on the GAW, and marked their positions with a Sharpie. I then removed the covers and used the holes in the angle to match drill the GAW (image 4). Once drilled, the covers were reinstalled and used as a template to draw the positions of teh semi-circular hole matching the cover hole (this will eventually take some wiring or tubing or whatever). I then removed both cover and angles and drilled for the two platenuts either side. the final result is shown in image 6, where two screws attach the plate to this angle. A lot of work for a simple cover attach device. By the way, whatever you do, make sure you rivet the angle to the web LAST. Don't ask me how I know! the pop rivets work well despite the limited spcae between web and skin. You need to push the rivet IN as you PULL the pop-riveter handles tight.

cover attach holes

tie-downs

drill stop

gear attach web drilled

LP4-3 poprivet positioned

cover in place