Archive for December, 2013

Installed Wing Tip Lenses – 4 hrs

December 29, 2013 Leave a comment

Sunday Dec 29, 2013

I trimmed the wing tip lenses to fit the recess in the wing tips. This was more time consuming than expected. I had to creep up very slowly on the final shape because there is no fixing it if you trim too much. I installed one #6-32 nut plate in each corner to attach the lenses. This is the left lens.


And this is the right lens.


Categories: Wing Tips

Started Installing Wing Tips – 10 hrs

December 28, 2013 Leave a comment

Saturday Dec 28, 2013

Work has kept me from making steady progress on the airplane the last few weeks. But today I was able to spend most of the day in the garage working on the wing tips. For a change I didn’t do any electrical wiring.

The first step was to measure the depth of the overlap between the wing skins and the tips and mask off the fiberglass for trimming. The flange on the tips is about 1/8 inch too deep. Then I started preparing the plexiglass lenses. I cut the molded lens in half using aluminum snips then cut off the flange around the perimeter. This allowed me to place the lenses on the wing tips and locate the approximate position of best fit. You can see them here temporarily taped in place.


Then I removed the lenses and trimmed the flange of the wing tips using a cutoff wheel. This is a very dirty job creating lots of fiberglass dust so I did it outside the garage with a respirator and safety glasses. After getting the overlap to fit well I could put the left wing tip onto the wing and identify where and how much to trim around the aileron. The plans call for 1/4 clearance between the fiberglass tip and the aileron so I marked it and crept up to that amount in several iterations. You want the aft edge of the tip to be aligned with the aileron when it is at nominal so there is some tweaking required to set the wing tip at that position then I match drilled through the pre-drilled holes in the wing skin and clecoed on the left tip.


You can see in this photo that the aft edge of the tip is not quite flush with the aft edge of the aileron and this looks bad. It seems this is normal based on reviewing posts of other builders so I needed to cut the aft edge off by about 1/4 inch. Fortunately this did not completely separate the upper and lower surfaces of the wing tip so the structure still maintained it’s shape. I’ll just have to reinforce the interior because it was weakened by the cut.


I repeated the process on the right wing tip and here is the result. This took quite a while to accomplish but this is good progress compared to my recent record.


Then I went back to trimming the lens for the right wing tip. I used the metal snips to rough it out then used my belt sander and scotchbrite wheel to fine tune it to fit the wing tip recess like a glove. One down, one to go.


Categories: Uncategorized, Wing Tips

Wired Backup GPS – 6 hrs

December 15, 2013 1 comment

Sunday Dec 15, 2013

Today I finished wiring the dimmer and annunciator controllers. You can see the green dimmer controller through the opening in the panel for the copilot’s EFIS. I also wired up the Garmin 18X GPS which sends data to the Gemini PFD and the ELT.


Categories: Avionics, Wiring

Wired Up Annunciator Lights – 5 hrs

December 8, 2013 2 comments

Sunday Dec 8, 2013

On Friday night I started wiring up the annunciator light panel. I happened to have red, yellow, green, and blue wire so I matched the colors to the lights I was wiring. Looks pretty. I wired the lights up first with long pigtails to be trimmed after the lights are mounted in the panel.


This photo shows the lights installed and the routing of the wires to the annunicator controllers which are mounted on the subpanel.


The key benefit of the annunicator controllers is the ability to test all lights with a simple push button switch. Mine is mounted right next to the lights. This photo shows all eight lights glowing as I press the test button. Further testing revealed that the landing light switch glows all the time – even when the switch is off. That is because I wired the annunciator controller to the VP-X side of the light switch and the VP-X apparently puts about 5V on the switch wires to measure continuity to ground. That confuses the annunicator controller. I’ll have to figure out how to fix that problem.


Categories: Avionics, Wiring

Powered Up Gemini PFD – 1.5 hrs

December 5, 2013 1 comment

Thursday Dec 5, 2013

Tonight I wired power to the Gemini PFD which is my independent backup flight display. It only took two pins for the power, one for dimmer control, and one for RS-232 input in a 9-pin D-sub connector. It powers up with the Avionics Master switch as recommended in the Trutrak installation manual. It is nice a bright – in fact it looks washed out in this picture because the camera can’t capture the full dynamic range making the colors look more muted than they really are. Ignore the big X on the Skyview screen because I had the ADAHRS disconnected when I took this photo.


I had some difficulty with the dimmer control because I wired my dimmer pot up backwards, meaning that the brightness goes does as I turn the pot counterclockwise. That is opposite the intuitive approach which is to get brighter going counterclockwise. I’ll have to rewire the pot.

Categories: Avionics, Wiring

More and More Wiring – 16 hrs

December 1, 2013 Leave a comment

Sunday Dec 1, 2103

With a dual Skyview system there are no less than 15 wires that need to be spliced together so both displays are connected in parallel to key components. This includes all the serial lines from the displays to the GPS, ADSB, VP-X, transponder, and radio, plus audio outputs from the displays to the audio panel/intercom. When I started thinking about using crimp splices for all of these it just seemed crude and inflexible for future upgrades. I considered using an avionics hub from but one with the capacity for 15 or more pins costs nearly $100 so I decided to make my own using D-sub connectors. It uses two 15-pin connectors (one for each Skyview display) and two 9-pin connectors that interface with the GPS, ADSB, VP-X, transponder, and radio. All it does is interconnect the signals from all these devices with the necessary splices. I used solder splices covered by heat shrink tubing. Here is a photo of the completed hub. The most expensive parts are the pins and sockets. all together it costs me about $30 to make.


Here is a shot of the hub mounted on the subpanel between the two Skyview displays. I installed a couple of nutplates on the hub after this photo was taken so the unit could be mounted with #6 screws from the aft side of the subpanel. Then I terminated the Skyview signals into mating D-sub connectors that plug right into the hub. This feels much cleaner to me than a mountain of crimp splices.


Over the holiday weekend I continued making electrical connections including wiring up the panel switches.  Here is a view of the switch wiring on the pilot’s side. I put a file folder under the wires just to help you see them better.


I also wired up the canopy latch switch which is wired to the annunciator panel.


So far, everything seems to be functioning properly. Once I got the avionics master switch wired up the aileron trim motor began to function properly from the pilots stick buttons. I also completed a calibration of the flap controller and set that up initially at least with three positions; 10, 20, and 35 degrees. That was just a guess but after I did the flap position indicator began to function appropriately on the Skyview engine page. You can see it in the lower right corner of the display next to the aileron trim display which also works. Very cool.


I needed a second GPS as an independent source for the ELT and the trutrak Gemini so I bought a Garmin 18X which runs on 12V power through a lighter adapter. I needed a place to mount that adapter so I borrowed an idea from Jason Beaver and mounted it on the right hand side behind the panel. I made a simple plate for the adapter and you can see where I plan to mount it in this view. I primed it but I plan to paint it to match the interior before riveting it down.


Categories: Avionics, Wiring