The center fuselage runs from the front spar carrythrough to the aft fuselage, or from the front of the seats to the rear of the baggage area.
This section looks like it will come together quickly as well, especially with the bulkheads already complete. Like the aft fuselage, Van's instructions are pretty limited, but this far along in the kit you get pretty good at figuring things out looking at the plans and thinking ahead a bit. Once the center section is done it will get mated to the aft fuselage.
Total Construction Time: 58 hours and counting
April 30, 2007 (3 hours)
Without someone available to help me start bucking the aft fuselage, I decided to start working on the center fuselage today. First I made some small spacer for the back of some of the seat ribs. Next I cut out part of the seat rib webs and part of the flanges where the control stick assembly runs through. I also cut out part of the rib flanges where they interfere with some of the wiring grommets and cut the 1 1/2" diameter holes in two of the ribs where the step bracket will pass through. Finally I assembled the seat and baggage ribs to the aft F-704 and the F-705 bulkheads. I wanted to attach the bottom skins, but almost all of the 3/32" cleco's are currently being used in the aft fuselage.
May 1, 2007 (1 hour)
Didn't do a lot today. Riveted the access cover plates and web stiffeners to the front spar carry through bulkhead. I also finally trimmed the seat belt brackets to fit around the seat rib flanges.
May 4, 2007 (3 hours)
When I put the bottom skin on I had some alignment issues with some of the rivet holes, then I remembered I hadn't fluted and angled the rib flanges yet. So I took it all back apart and fluted and bent the flanges to 90°. I put it back together and there's no change. The bottom skin rivet holes appear to be 1/16" too far forward at the F-705 bulkhead and baggage ribs. Spoke with Gus at Van's and haven't come up with a solution yet. I'm doing some more checking to see if I can figure out where the problem is, but everything looks put together right. Worst case, I'll have to wait until Monday to call Van's again. I also made the four small attach straps for the outboard baggage ribs.
May 5, 2007 (1 hour)
Had a little time to kill so I started deburring a few of the baggage ribs. Had a few other builders reply on VAF that their bottom skin rivet holes aligned the same way and I also took a look at Pete Howell's rivet spacing on the bottom of his plane. Looks like it all fits the way it's supposed to so I cleco'ed it all together. I started at the F-705 bulkhead then did the baggage ribs. Next I angled the baggage ribs until the seat rib rivet holes aligned with the skin rivet holes.
May 6, 2007 (7 hours)
Started by match drilling the bottom skin rivet holes along the ribs and bulkheads. Next I modified the baggage side skin ribs to align the edge with the edge of the skins and drilled these. I also match drilled the ribs to the bulkheads. I had to run to the hardware store to get some 7/16"x4" bolts to join the two F-704 bulkhead halves. I had glued two pieces of MDF for the temporary spar spacer the other day, but when I ran them through my planer they ended up slightly too thin. I decided to make some new ones quick, but rather than wait for the glue to dry, I just used some short screws which I countersunk so my planer wouldn't catch them. Took my time and got the thickness spot on with the second set. Finally I match drilled the bottom skins and side plates to the front bulkhead, then took it all apart for deburring, dimpling and priming.
May 7, 2007 (1 hour)
Couldn't sleep early this morning, so I popped out into the garage around 4 a.m. and removed the plastic from the rivet lines on the outside face of the F-976 center skin.
May 8, 2007 (1 hour)
Finished up deburring the baggage ribs and got a good start on the two side skin ribs.
May 9, 2007 (2 hours)
Half way through the seat ribs.
May 10, 2007 (2 hours)
Almost done with the seat ribs.
May 11, 2007 (1 hour)
Finished up the seat ribs in the morning before work.
May 12, 2007 (8 hours)
Decided to deburr the two exterior seat ribs even though they aren't fit and match drilled yet. Also filed out part of the flanges of the two side skin ribs for where the step mounts, and also filed out a couple of spots on the seat rib flanges for wiring grommets. I also deburred the short removable parts of the center two seat ribs. Next I deburred rivet holes in the seat, side skin and baggage ribs, bottom skin and bulkheads. Also drilled the 1/4" diameter holes in the forward F-704 bulkhead where the spacers go, which I was nervous about for no reason. Late in the evening I deburred the edges of the bottom skin and then dimpled all the parts except the F-704 bulkheads and bottom skin. I also machine countersunk the outboard 5 rivets on each end of the forward F-704 bulkhead.
May 14, 2007 (1 hour)
Dimpled the F-704 bulkhead bottom flanges. I also temporarily joined the F-972 forward bottom skin to the F-976 center bottom skin and match drilled the holes. In the evening I dimpled about half of the bottom skin rivet holes.
May 16, 2007 (1 hour)
Finished dimpling the bottom skin and miscellaneous other prep work. All ready to prime my parts.
May 25, 2007 (3 hours)
Back home after a week in India. Still feeling the jet lag, but managed to go out in the evening and prep the center section parts for priming.
May 26, 2007 (4 hours)
Shot primer on the parts this morning. Later in the evening I riveted the seat ribs to the F-904 bulkhead. I also played with different panel ideas over the past few days, with one idea shown below.
May 27, 2007 (5 hours)
Woke up early (still have jet-lag) so I riveted the seat and baggage ribs to the F-905 spar. Next I bolted the seat belt brackets in place. Next I flipped it over and attached the bottom skin, but I'll need some help to buck these rivets. In the meantime I widened the slots in the aft bulkheads where the longerons pass through, marked lines on the outer seat ribs in preparation for fluting and drilling, and also drilled a second wiring hole in the F-906 bulkhead.
May 28, 2007 (1 hour)
Deburred the F-904H side panels, marked the center lines of the outer seat ribs for drilling. Not much else I can do until I get the bottom skin riveted.
June 3, 2007 (2 hours)
The last week I've been pretty busy with work, family stuff and scout camp. I was finally able to get back to working on the fuselage. Tracy and I riveted the bottom center skin to the ribs. Still playing with panel ideas. I really like the layout below with the dual GRT EFIS screens, with the second one serving as both engine and also a moving map display. In the picture below you can see I temporarily attached the subpanel and ribs to see how things interfere. I'll likely need to modify the rib on the left for the GRT screen, but I want to avoid having to modify the center rib where the canopy support bar rises from.
June 4, 2007 (3 hours)
Today was a really exciting part of the build - joining the aft and center fuselage sections. First I cleco'ed and screwed the seat and baggage skins in place to add stiffness to the center section. I was a bit nervous about balancing the center section upside-down on the two bulkhead frames, but they stayed perched there pretty well. Getting the two sections together was a bit tricky to get the rear bottom skin to slide between the center bottom skin and the ends of the ribs. I ended up removing one of the rear baggage skins and then I was able to get them together. I still needed to modify the aft canopy decks per the plans. I ran out of time to get the longerons in place.
June 5, 2007 (2 hours)
Got the longerons in place. Next I drilled the 1 1/2" diameter holes in the side skins for the steps. Finally I cleco'ed the side skins in place as well as the two armrests. This this is getting really long!!!
June 6, 2007 (3 hours)
This evening I started by match drilling the armrests. The next task is to make the conical bends in the side skins where the center fuselage meets the aft fuselage. I've heard of a few builders having a crack form near the front of the cuurve where the bend is really tight, so first I deburred the small radius hole at this spot. Then I simply followed Van's direction of clamping the skin at the end of the table, clecoing an angle at the outer edge, grabbing it with a vise grip and bending. Nothing to it and they came out quite nice. Note to other builders, I had already dimpled the corner ribs and the bottom skin where the side skins slips in, so had to dimple this prior to reattaching the skins in place. Ideally you shouldn't dimple the ribs and bottom skin so you can match drill.
June 7, 2007 (2 hours)
Drilled the rivet holes in the longerons all the way from the aft bulkhead to the F-704 bulkheads. That's a lot of holes to drill.
June 8, 2007 (1 hour)
Drilled the rivet holes in the longerons forward of the F-704 bulkheads to where the firewall attaches.