Fuel Tank Bracket

Time: 2 Hours

Once the wings are removed you have access to the fuel tank attach bracket that is part of the wing structure. If you remember I drilled this bracket while it was mated to the bracket that is part of the fuselage. Now that the hole has been drilled in the wing side bracket you need to extend the hole to a slot. The theory for this is in the event of an emergency landing or accident you want the wings to shear away from the fuselage as they absorb some of the energy that you have during an accident. The wings are meant to break away aft or towards the tail so you want the forward part of the wing to be easily separated in this event. This slot allows the bolt to support the inboard end of the fuel tank up and down but will shear away as the wings are bent back in an accident. So I started with a mark 1/4″ wide and cut the slot just inside of those lines. I then used a file to clean up the edges and open until a 1/4″ bolt would easily slide through the slot. Filing this thick bracket is what took the most time but I wanted to make sure I didn’t take too much. All in all I’m real happy with how they turned out. 

Flap Fairing’s

Time: 4 Hours

I got a little time in the shop after some work tasks that needed to be done. My goal today was to finish up the fairing’s that close the gap from the wings to the fuselage. All they needed was the edges to be sanded, holes deburred and the holes dimpled for #8 screws. That didn’t take too long and I forgot to snap a photo of the work. I moved on to the flap fairing’s which needed the same work except the dimples were for flush rivets. After the edges were done and holes dimpled I scuffed up the inside surface and primed them. 

While those were drying I dimpled the matching holes on the fuselage using my blind rivet dimple set. 

When the primer was dry I worked the edges to get them to lay tight against the fueelage using my edge roller. Once I was happy with the fit I clecko’ed them in place to rivet. I was able to get about half of them by myself using the bucking bar and rivet gun. Once my buddy Glenn got to the shop I borrowed him to help finish the rest of the rivets. 

I was real happy with how they turned out as they have a lot of curves and can pose a problem getting them to sit flush. Not a lot to show but progress. Any task on the RV-8 is a good one and one step closer to the end. 

Wing/Fuselage Flashing

Time: 8 Hours

With the wings removed I can finish up the work on the holes drilled for the flashing that closes up the wing/fuselage gap. The holes were drilled with the wings in place but you don’t have enough access to finish the work that is required. All these holes will eventually have a acres in them to hold the flashing in place but allow easy removal for work. All of the holes will get a nutplate for a #8 screw. The flashing holes will be dimpled for flush screws so all the underlying skins on the wing will either be dimpled or countersunk depending on the area. The fuel tank edge can be dimpled as well as the bottom wing skin. The top has to be countersunk since it has three layers due to the extra wing walk material that beefs up the area to walk on. I started with the fuel tanks working on both wings. 

I used one winged nutplates for the two spots where the fuel tanks reach the wing spar. You could remove the fuel tank and have access to rivet a normal two winged nutplates. With the one winged nutplates I could rivet them without removing the tanks. Thanks again to Glenn for having his wings here so that I could eyeball them when I was scratching my head on how to rivet the normal ones. Once I had all the tank ones done I moved to the single nutplate that falls on the wing spar flange. I countersunk the rivet holes for the nutplate and grabbed my rivet gun and bucking bar and set those rivets. With the nutplate in position I countersunk the screw hole with a #30 bit. This bit head will fit inside the nutplate screw hole and keep it aligned. 

From here I worked my way up the bottom skins which just needed nutplate rivet holes drilled and dimpled as well as the #8 holes dimpled. 

All the holes on the top skin will be treated like the wing spar flange and had the nutplate riveted in place and the. The screw hole countersunk. 

With all these holes done I can put the wingtips back on and store the wings for later work, landing/taxi light wiring and install, and out of the way. 

During a break I ordered and ran to pick up a couple boxes of screws from McMaster Carr. I wanted to get some black 8-32 torx screws 1/2″ long for my instrument panel. I thought these would look cool vs the gold colored ones that I already had. 

I though these looked so cool I ordered a box of black 8-32 phillips flush screws for my armrests and side panels from MicroFasteners.com as they carry 100° head screws in black and stainless. 
 My girl and the kids got me a Aircraft Spruce gift card for Father’s Day so I used that yesterday and ordered the Dynon autopilot control head that sits next to the intercom on my panel. I wanted this now so that I could test my trim buttons on the grips as well as the trim motors like the one I just installed for the roll trim. That should be here by the weekend for me to install. Thanks T, Drake, Chandler, Ellie and Cody. 

Wing’s Off

Time: 10 Hours 

This weekend was another big milestone – I removed the wings! These won’t go back on until the paint is done. To prep for this task I had just a few items to take care of. The first was to drill all the holes that hold the wing/fuselage flashing on to a #19 for the eventual screws that will go there. Then I removed the flaps and ailerons to make the wings a little lighter for lifting. 

Then with a couple of hits to the temporary bolts that were holding the wing spar along with Glenn moving the tip of the wing up and down to take pressure off the bolts they slid right out. We then lifted them off the fuselage and put them back in their cradle for the remainder of work needed on them. 

Wow that was fun and I have so much more room to work now! One of the avionics I will have in my instrument panel is the Garmin GTN-625. This is a certified GPS navigation source and is the little brother to the 650. The only difference is that it doesn’t have the COM/NAV portion like the 650. All I wanted was the GPS enroute and approach capabilities. I have two Dynon radios and I will never do an ILS or VOR approach in this plane since RVAV/GPS approaches are all over the place.  Plus I didn’t want to put any mor antanaes on the plane. I won’t buy this unit until I’m all done but I did want to wire it now. There are three things that I needed for this. First is the tray that the unit will actually slide into and supports the unit. The second is the backplate which houses all the connections and the third is the connector kit that allows you to run wires to the backplate. I got these from JA Air in KARR where I fly out of. They had the tray but had to order the rest for me.

 So I moved on to attaching the tray to the instrument panel. It will be connected with four screws that will go into the brackets that SteinAir gave me when they cut the panel. I drill them for four #6 nutplates for the screws to go into. 

I squeezed a few rivets and the nutplates were done. 

I test fit the tray to make sure all was well and it looked great. 

Now that the panel was all done I was able to paint it for its final install. When the paint was dry I screwed in the Garmin tray and put them both back in the RV. 

I then decided to do a little wiring one was to remove the ARINC harness that I had originally built and run from the module up to the panel area. The reason is that SteinAir recommended sheilded wire which I didn’t use. 

So I rebuilt it with the correct wires, 22g two conductor wires. One for the TX set of wires, one for the RX set of wires and one for the serial line. While I was up messing with the wires behind the panel I decided to clean up the two Dynon screen harnesses. I have one for the 10″ and one for the 7″ screen. There were a few sets of wires that I wasn’t sure I would use or not so I just left it all hanging for the time being. They leave wires for contactor inputs if you so desire, all mine will be going through the VP-X so I won’t need them. The other set was for another serial input and those won’t be needed either. The last wire was for dimming capability from an outside dimmer control that I wasn’t going to use. So I gathered up all those wires and made a tight coil and zip tied them to just hang behind the screens after the install. I also zip tied the rest of the harness wires to clean them up leaving the GPS antanae wires out. I decided to terminate these wires in a connector so that when I finally decide where I will put the antanae I can just run the wires to the pane and plug it in. 

Now all that needs to be connected to these harnesses is the backup battery’s and the USB ports. It always seems that when I’m working on a task I see other items in that area that I want to work on. This was the same here as I was standing on the left side of the fuselage by the panel. When I installed the ELT remote head with tiny screws and nuts a while ago I didn’t think that I would ever have to remove that this after the RV was finished, but I found out that those part has a battery in it (I thought the one in the speaker housing was it).  The possibility of getting those little nuts in place in the blind would be impossible. So as I sat there looking at he back of the panel I had an idea. These 4-40 screws are small and don’t need to be very tight. I decided to grab some 1/8″ thick bar and cut two small peices, one for the left side of the ELT opening and one for the right. I drilled and tapped them using the ELT holes and used some of my T-88 structural adhesive to bond them to the back of the panel side peice. Now to remove the ELT remote I will just have to unscrew the screws from the front and not worry about nuts on the back. 

I was still in the mood for wiring, and not sanding fiberglass, so another task that I had been putting off was the roll trim motor wiring and install I will have pitch trim which is in the left elevator and roll trim which is in the floor just by my left hip as I sit down. There are five small 26g wires for each of the trim servos. Two are for the movement wither in or out based on which wire is getting power. The other three are for the trim indication, mine will be a widget on the Dynon screen that gets produced by the EMS(Engine Monitoring System) which has a bunch of blank inputs that you can use for items like this. To connect these tiny wires as they get to the servos I’m using RC aircraft/car micro connectors that Glenn used on his. The current that these carry is really low so these connectors work great. The down side is that they just have little prongs that stick out that you have to solder the wires on to. This meant that I would have to solder inside the fuselage bent over the edge. Glenn’s soldering clamps worked well for this. First up was to cut and drill the push tube based of the dimensions in the plans. This rod has two large cotter pins that act as points for springs attach to. Then the springs attach to the bottom of the control column tube. This rod slides into a bushing on one end and connects to the servo on the other with a pin. Then the rod moves left and right as needed but the springs allow the pilot to override the trim or just to use the controls when the trim isn’t working. 

I then test fit it all in place to make sure the movement was not binding. 

Then it was off to getting the connectors soldered. I made sure to put on shrink tube for the whole wire run, the shrink tube label and the small shrink tube to cover the individual soldered wires. 

I made sure to line the wires up on the servo so they matched the wire run and soldered them. 

With the wires all soldered I made the connection from the rod to the servo. 

More Fiberglass Work

Time: 8 Hours

I have been slowly working on all for the fiberglass parts on the wing tips and VS/HS. The forward peices just ahead of the elevators and rudder are proving to be a pain to fill. Getting into the areas between the flanges is a littl tough. I’m using a larg popsicle stick with sandpaper glued to it to get into these spaces. These areas will probably take a couple of try’s to get just right. Man do I hate sanding fiberglass! On a side note I did get my AeroLED taillight from Aircraft Spruce this week. I was planning on using a watertight connector for this light since it will be in the bottom of the rudder and will be exposed to water from time to time. The problem was that the area in the aft end of the rudder bottom fiberglass gets pretty tight before the flair for the light. The issue with that is this peice will be riveted on and I will have to slide the cable in from the front and make it back to the hole. With a large connector it was impossibe. So I just used a small 5 place Molex connector that is easy to slide into place. 

I will figure a way to waterproof it after the connection between the light and harness is made. Maybe a long peice of shrink tube that covers the connector will do the job. While I was letting some epoxy cure for the next day I moved on to a little task on the flaps electrical connection. There is a side panel on the left side of the passenger seat that will cover up the flap motor. This creates a space behind it that I was able to install a two place terminal block to allow easy connection of the flap wires. This block will be screwed down to the floor that will eventually be permently riveted. I located the perfect spot and drilled for two #8 screws and riveted a couple of nutplates for them. 

I removed the terminal block and crimped the terminals on the two wires for the flap motor and the two wires from the VP-X.  Then I connected them for continued use of the flaps without the floor. 

I finished up a few fiberglass filling jobs as well. 

One fill job is on the bottom of the rudder where the fiberglass cap goes around the rudder cable attach horns. 

I have a lot of filling and sanding to go but I’m just going at it one step at a time. A few more standings on the wing tips and I’ll be able to call them done and be able to remove the wings.