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Wings Removed, Front Deck Priming – 8 hrs

March 3, 2012 Leave a comment

Saturday Mar 3, 2012

Today was a pretty good day on the project. I got all the front deck parts prepared and primed for final assembly and I got the wings removed from the fuselage. But I get ahead of myself.

The front deck is a bit tricky because it was not designed for modern glass cockpit EFIS displays. There is a main support for the instrument panel that falls right where the primary flight display needs to be. I won’t be installing components in the panel for a while but I need to assemble the front deck structure now. I did some research on the web and learned that most builders cut off the left F-745 rib at the sub-panel and relocate the forward part to the left or right of the PFD. At the moment I am planning a 10- inch Skyview display on the pilot’s side and a 7-inch display on the co-pilot side as back-up – something like the figure below.

Click to enlarge image.

The existing F-745 rib on the left falls right in the middle of the Skyview so that one will clearly need to be relocated. I cut the rib at the sub-panel as shown below. The right rib can probably be adapted to work below the 7-inch Skyview so I left that rib alone for now.

I clecoed the front deck structure back together to make sure the cut was good and as you can see below, the forward section of the F-745 is now available to be relocated.

I spent the next hour or two deburring, scuffing, and dimpling the rest of the front deck parts to get ready for priming. There is quite a good size pile of parts.I also had the two wing root fairings (not shown).

A couple hours later I had the parts cleaned, dried, and primed using good ole Stewart Systems Ekoprime.

This photo is the front deck skin primed along the ribs on the inside surface.

Since I recently finished fitting the wing root fairings I was able to finally take the wings back off the fuselage. I have been anxious to do this because it has been such a pain maneuvering myself in the garage with wings going almost all the way from one wall to the other. It has also been hard working on anything inside the cockpit while reaching over the wings. So I was able to get the help of Denise and Jennifer to remove both wings and put them back on the cradle. That is probably the last time they will be on the fuselage until I move this project to the airport for final preparation for first flight.

It’s really nice to be able to walk around the fuselage without squeezing through the narrow confines around the wings.

Late in the day I was actually able to start riveting a few parts of the front deck together. Here is the center sub-panel with the hat section, stub ribs and forward center rib. Update: I learned about six week later that I should not have riveted the hat section to the subpanel yet. The plans don’t say it but you need to install some nut plates in the hat section for the canopy release mechanism and it is much easier to do that before riveting the hat section to the subpanel.

And here are the left and right outboard sections of the sub-panel with the seal strips riveted on.

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Fitting Wing Root Fairings, Misc Front Deck – 7 hrs

February 25, 2012 Leave a comment

Saturday Feb 25, 2012

With the wing root fairings in hand from the finishing kit I got the first real work done on the airplane in over a week. Some of the fairing holes line up with existing nutplates in the wing and some have to be match drilled using the fairing as the guide. After an initial fitting I bent the fairings along the leading edge to make them fit a bit better. I found that the edge of the fairings rub the side skin of the fuselage so I trimmed a bit off to make sure the fairings were located properly before match drilling. Then I opened up the holes to #12 for #8 screws. Then I used a piece of scrap .187 thick aluminum to mark a line on the inboard edges of each fairing which I used as a guide for trimming. After that I dimpled the holes in the fairings and put them aside for priming.

But I test fit a piece of the foot fairing seal material to see how it fits. It is snug. You don’t really want less than 3/16 gap between the edge of the fairing and the skin.

With the root fairing done I rechecked the alignment of the ailerons and flaps using the bellcrank tool. I made a couple of small adjustments to try to get the pushrod lengths all set correctly for normal level flight. With that done I can finally take the wings back off the fuselage and free up some room in this garage. But I need some help to do that so maybe tomorrow I can get the help of Jennifer and Denise.

Next I located the F-697 channel (also in the finishing kit), cut it to length and beveled one end. To locate it on the F-768A sub-panel I located and drilled one hole by dimensions on the drawing. I clecoed the channel to the sub-panel in that hole and aligned the channel vertical using centerlines I had drawn on the channel flanges. You can see the parts clecoed together in the picture below. the lower left cleco is holding the channel.

Then I drilled all the other holes in the channel flanges using the pre-drilled holes in the F-768A sub-panel.

Here is the assembly from the back side.

You have to cut a little notch in the channel flange where it overlaps the cut-out in the sub-panel for the canopy release handle.

Then I clecoed the sub-panel back onto the fuselage.

Next up was making the F-768D seal support angles. These little buggers took quite a while to make with all the holes and notches being manually located and cut.

Then I located the F-768Ds on the outboard sub-panels offset by 1/8 inch from the edge of the sub-panel.

With both of those done I clecoed them back onto the fuselage.

It feels good to make some progress again.

External Fuel Vent Lines – 1.5 hrs

January 15, 2012 Leave a comment

Sunday Jan 15, 2012

Having completed the installation of the main fuel lines to the selector valve I worked on the short fuel vent lines that run from the side of the fuselage to the vent fitting on the tank. I started with a piece of 1/4 inch tubing 11.75 inches long and I installed the nut and sleeve on the tank end first. Then I planned the route to the fuselage fitting. The plans show it going over the tank bracket and then down to the fitting but that looked like it would run into the main fuel line I just installed. So instead I bent the tube downard at an angle and went under the tank bracket. It was easy to make the first bend by eyeball, then measure where to make the second bend to come under the bracket with about 1/4 inch clearance. After making that bend it was no problem to measure where to make the last 90 degree bend to go straight into the fitting. What I like about this route is I could use the Imperial tube bender for all bends so they are all nice bends. None are too close to the AN sleeves for the bender. The completed tubing section is shown below for the left tank. It still has some of my Sharpie markings on it.

Here is how it looks installed.

The other side was exactly the same process except I made the first bend by mirror imaging the left side. Here is how it looks installed also.

I decided next to put the fuel pump back in the cabin to make sure the clearances to the new main fuel lines were all good. As you can see in the next photo its all good. I love the way this all fits with the new style Andair fuel pump and the trim cable.

The brake lines are next on the agenda so I installed the an fittings on the firewall per the plans. I’m still deciding whether to install a parking brake so I will work on the rigid lines to the weldments first.

Finished Tank to Selector Fuel Lines – 6 hrs

January 14, 2012 Leave a comment

Saturday Jan 14, 2012

To finish the fuel line on the left side today I needed to put the wing back on the fuselage and measure as closely as I can the dimensions from the fuel tank attach bracket to the AN fitting on the tank so I could get the final bend and flare formed right to fit the tank. There is not much give in this rigid aluminum tube so it is critical to get it right or the whole tube may have to be scrapped.

But before I put the wing on I needed to drill some holes in the side of the fuselage for the pitot and AOA plastic tube routing from the wing into the fuselage. I have been grappling with this issue in my head for some time because it is not in the plans and I haven’t found any examples on the forums or on the web that fit my needs. I do not plan to have any steam gauges up front on the panel that require pitot or static pressure lines. Only the Skyview ADAHRS module in the tail cone will need it. But I want to keep the door open in the future in case I decide to add a backup instrument like a Dynon D6 later. So my challenge now is to get the pitot and AOA lines from the wing root near the main spar to the aft cone of the fuselage, avoiding any possible interference with the flight controls which are nearby, provide an easy way to connect those lines when the wings are mated for the last time, and identifying a good location where I can T-off the pitot line in the future to route it to the panel.

So I finally have a plan that I think will do all of those things which I am going to document here over the next few posts but it starts with drilling two new holes in the side of the fuselage  at the wing root to get the pitot and AOA lines into the cabin under the pilots seat. So before remating the wing I drilled those hole this morning as you see in the photo below. The are the two new holes on the right of the big aileron pushrod tube hole with rubber grommets installed. Those grommets are sized for the plastic pitot and AOA lines. The new holes are on the aft side of the pushrod hole to allow the plastic lines to route around the aileron pushrod in the gap between the inboard rib and the fuselage skin because there appears to be no good place to pass through the skin in front of the pushrod and that area is very crowded anyway.

Part 2 of the pitot and AOA routing is to install 90 degree quick disconnect fittings on the pitot and AOa lines between the wing inboard rib and the fuselage skin. These fittings come with mounting hardware so I plan to make small brackets to secure the orientation of the fittings to point around the aileron pushrod one going above and one going below as you can see in the photo below. Now with that small detour task completed I can go back to finishing the fuel line routing.

So then I put the wing back on the fuselage and made measurements for the final bending and flaring of the fuel line. The distance from the tank attach bracket forward to the centeline of the fitting tells me where to locate the last 90 degree bend and the distance from the tank attach bracket hole outboard to the tank AN fitting tells me where to cut the tube and flare it. I was very cautious about this because I did not want to screw up on the last steps and scrap the whole fuel line. I even made a test piece for the last bend which I marked out and bent to make sure I had the reference marks right to make the tube line up with the fitting.

Then I took the wing back off, removed the tank attach bracket from the fuselage again and gently bent the tube out away from the fuselage to get just enough room to use my Imperial 470 tube bender. That is the only way I can get a nice tight 1-inch bend radius without kinking the tube. After I made the bend in the actual fuel line I gently bent it back parallel with the fuselage and installed the tank attach bracket again. Yes, a few iterations were required to recenter the tube with the hole in the bracket. Then I marked the tube end based on the distance I measured from the center of the hole in the attach bracket to the end of the tank AN fitting. I slipped an AN818 nut and AN819 sleeve onto the tube and flared it with the Parker Rolo-flare tool. The photo below shows the result.

Next came the big test – the wing was remated and the fuel line was mated to the tank. Actually it went right on without fuss. As you can see in the photo below, the fuel line is almost dead center in the hole of the attach bracket which is what I was shooting for. Yipee, one down and one to go!

The right side fuel line was less stressing and went quicker having learned what I did on the first line. I created a mirror image set of bends on the tube for the area under the fuel valve and routed the rest of the tube as before. Here is how the interior of the cabin looks with both lines in place.

This is the outside of the fuselage on the right side all done and mated. I actually got a little sloppy on the marking of the final bend and the AN fitting came out about 1/8 inch too far forward for the tank fitting but I was able to reshape the tube slightly between the fuselage exit hole and the fitting to bring it into alignment. Lesson to self – don’t get too comfortable or you’ll make mistakes.

Here is another view of the interior showing the s-bend where the tube exits the side skin.

Tank to Selector Fuel Lines, Round 2 – 2 hrs

January 14, 2012 Leave a comment

Friday Jan 13, 2012

Today I ripped the whole fuel line out that I installed yesterday. After sleeping on it last night I decided that I could and should do better. One thing I was not satisfied with was the area under the fuel valve. Last time I formed the first bend before installing the tube on the spar but I formed the second bend after the tube was routed through the weldment and side wall. This resulted in a sloppy large bend. I decided to form the first two bends under the fuel valve before installing the tube. To get it right I made a short test piece from the AN fitting on the valve to a few inches beyond the first snap bushing. Actually it took two attempts to get this right but once I did I had a formula for a good fit. The tube makes a 90 degree bend 2.7 inches below the AN fitting going not perpendicular but at a 60 degree angle to the main spar. Then it turns 60 degrees to enter the first snap bushing. Both of these bends are made with my Imperial 470 tube bender so they are very clean bends with absolutely no kinking. I installed an AN fitting on the test piece to make sure it was engaging the valve correctly for fit purposes.

Then I took a new 40-inch long piece of tubing, slipped and AN819 sleeve on the end and flared it, then formed the first two bends like the test piece.  In the picture below you can see the test piece next to the 40 inch long piece to be installed. You can see how I duplicated the shape so I should not have to shape this area under the fuel valve once I get it routed.

Bruce Swayze did a great job of laying out how he installed his fuel lines on his web site. Following his lead I bent the line into a large arch and feed it through the first snap bushing. I removed the bracket for the second snap bushing from the spar to make pushing it through a little easier. It’s just slipped over the tube and floats until the tube is routed through the side wall. O yeah, don’t forget to slip the AN818 nut onto the tube before inserting it through the first snap bushing!

I also discovered another error I made last time – I ran the tube through the lowest hole in the weldment. Bruce ran it through the middle hole. Today I found that makes a huge difference in making it easier to route through the weldment and out the side hole. In the photo below you can see how the tube now routes through the weldment and out the side hole in a relatively gentle bend. It will not do that routed through the lowest hole. It must make a compound curve s-bend which is really difficult to work along the tube.

In this picture you can see how it now exits the side skin following that gentle arc.

Once I got the tube fully inserted I connected the fuel valve AN fitting which fit nicely this time.

Then I formed the s-bend between the weldment and the side wall. The s-bend makes it exit the side skin perpendicular to the surface but I only have to do this once now that the tube is in place. I used a 1/2 inch wood dowel and a cut-off broom handle – one between the tube and the side wall and the other down through that hole in the top of the weldment to get into the inside radius of each bend. I used the coiled wire bender for this process too of course so the tube would not collapse or kink while bending and to protect the tube from the sharp edges of the weldment and the side wall holes.

In the photo you can see how it now runs straight out the side hole and well centered on the hole.

Then I formed a 90 degree bend on the outside of the fuselage to run the tube forward toward the fuel tank fitting. I used the coiled wire bender here also and the broom stick handle against the side skin to form the radius. Now is the time to slip the rubber grommets on the tube and insert then into the side skin holes. The first grommet must be pushed through to the inside of the fuselage and then the second grommet installed on the outer skin as seen below.

This next picture shows the grommet installed on the inside doubler.

Finally tonight I removed the tank attach bracket on the side of the fuselage and finished forming the tube and tweaking it until it ran straight through the hole in the bracket. This took some trial and error, putting the bracket on to check alignment and taking it back off to make adjustments but I didn’t have to install the nuts each time so it only took a few minutes.

I’m almost home on this tube run but I still need to form the last bend and put an AN fitting on to mate to the tank. But that will have to wait until tomorrow.

Tank to Selector Fuel Line – 2 hrs

January 12, 2012 Leave a comment

Thursday Jan 12, 2012

I worked on installing the right fuel line that runs from the tank to he fuels selector valve. I found some tips on how to do this on the forums. I started by measuring and making the first bend nearest the valve using a 40-inch long piece of 3/8 tubing. I flared the end for the AN fitting. Then I installed this piece through the snap bushings along the spar and into the gear weldment.

Routing through the weldment and out the side hole proved to be more difficult than I expected. I had to shape the s-bend and walk it along the tube as I fed the tube through. I used a coiled wire tube bender to help minimize kinks in the tube.

When it exited out of the side I ran it foward toward the fuel tank AN fitting. This still needs a 90 degree bend and a flair to mate to the tank.

Looking at the results I am not sure I am satisfied with this. There are some kinks near the forward end and I think I will sleep on this before continuing.

Fuel Tank Bracket Nutplate – 0.5 hr

January 11, 2012 Leave a comment

Wednesday Jan 11, 2012

I’ve been thinking about how I’m going to install the main fuel lines that run from the tanks to the fuel tank selector valve. I’ve also been thinking a lot about how I’m going to route the pitot and AOA lines from the left wing through the fuselage. In the mean time, tonight I installed a nutplate on the left fuel tank bracket. You can see it in the photo below.

Categories: Fuselage, Mating the Wings