N254MR

Well there was no "local" graphics shop that could do the job, but thanks to All-Out Graphics in West Vancouver, BC, the letters / legends arrived very promptly in the mail yesterday, ready to go. Of course, turns out there's some last minute mods that need to be made on these already-painted panels, and I may decide to put a coat of clear coat over the top of the letters, in which casd I have to light sand the panels with 600 grit to create an adhesion surface for the clear coat... and the sanding has to happen before the letters go on.

Meanwhile, today I did some more wire unweaving under the panel (turns out I hadn't done the strobe DC power and the flap controller ground wires) and prepped the firewall for the new throttle cable grommet hole. That meant moving some wiring on the front side, masking things off so drilling pieces don't fall on other components, etc. Will cut tomorrow.

Another milestone. To the unpracticed eye, the picture below may look much like all the other spaghetti photos sprinkled over these pages the last couple of months. But hark, 'tis not so! For in this picture, for the first time, are all the wires that will reside behind and under the panel. The last custom harness, for the elevator trim and flaperon LED indicator bar lights, went in this afteroon. (It ends in the 9-pin D-sub connector hanging down in the lower middle of the photo.) Even better, the wires are all in their proper routes and bundles! There will be more "weaving" (more like unweaving, actually) as I work out toward the sides and ends of the wires, doing the terminations, but everything is in place where it's supposed to be. The only things missing are wing wire feeds that will run from the left side switches out to NAV and landing lights (there are no holes in the lower cabin sides for them to run into the wing struts yet) and the XM WX receiver antenna that AFS hasn't shipped yet. There will be a couple of small harness attached to the panels themselves -- mostly for inidicator/annunciator LEDs. Other than that, they're finally all there. The DC power & alternator controls, the cabin & panel lighting and instrument connections, coaxial antenna feeds, the avionics and flap controls, the sensors and indicator feeds, the ARINC bus, the magnetometer & OAT wires, the ground power circuits, and more.

Actually, the only reason it still looks this messy is that there's a lot of excess wire at the ends of runs, extra wire that will be cut off as the wire ends are cut to final lengths and the terminations are installed.

Finished the "stencil" for the right panel legends pretty quickly this morning. The two rectangle cutouts at the top left are for the carbon monoxide (CO) monitor at the top, and the Hobbs meter underneath, which tracks total cumulative engine time. The two holes at the lower left are for cigarette lighter style power outlets for portable accessories, iPods™, etc. The external ground power switch at the lower right will have a top-hinged yellow guard that pretty much covers the area between the mounting hole and the small LED annunciator hole just below the lettering. The LED will be ON whenever the switch is up (ON) and powered from the battery bus so it will shine whether there is external power connected or not. Consequently, there will be too alerts that the switch is ON -- the LED and the open yellow guard. The ground power switch will control a small relay, which itself will be powered by incoming external power, if any. Of course, the external power circuitry will have polarity & over voltage protection, and fuse. A good chunk of the rest of the space on this sub-panel will be occupied by various mandatory & optional information plackards.

A few notes on the panel design philosophy have been added to the Library, Project Documents, Design & CAD section.

The most recent version of the master electrical spreadsheet has been uploaded, containing oodles of changes and refinements in almost every section (tabbed page) since the last (5/08/08) version was posted. The biggest changes have been in the fuse assignments and switch categories, each of which have garnered considerable re-thinking as the build-out progresses. For example, I've reassigned the transponder to the E-bus because I don't want it to shut off automagically when killing the Main bus, especially if I'm using the air traffic control system (ATC) for flight following. If I'm already in the ATC system, and may be having a problem, it's better that I keep it up until a manual shutdown is warranted.

I've also reinstated the EFIS 2 ALT FEED switch. The rationale for that follows.

Each of the two electronic flight information systems (EFIS) units has an independent (redundant) Airborne Heading-Attitude Reference System (AHARS) which control the primary flight instruments. Each EFIS has three possible sources of DC power: 1) the Main power lead, 2) a Backup power lead, and 3) an internal Backup Battery. When the main power fails, the EFIS next draws from the backup power circuit (if available), then it goes into a 30 second time-out with a "crawl line" at the bottom of the screen showing it will shutdown unless the pilot pushes any button to make it stay ON using its internal battery.

Have made a bunch of miniscule adjustments to the positioning. It's amazing how precise you can be in CAD if you zoom in to the work, making it much larger, and making precise positioning much easier. After quite a bunch of that tweaking on a micro level, here's an image of the left panel legend "stencil" which was created using just the text and lines layers of the CAD file, converted from white to black. I found that by holding this up to the actual panel, with light behind, I can check the alignment quite easily. I'll take it to a graphics shop for them to produce the vinyl transfer in white.

Most of today has been spent up close and personal with TurboCAD™. First I scanned an image of the left side panel and imported it to a new CAD file. Next, using additional layers for "text" and "lines" I created a "stencil" or template from which vinyl transfer lettering can be made. The image below is a composite of all the layers, but I can print out just the letters and line layers -- in black instead of white -- and take them to a graphics shop to produce the lettering. With any luck, I'll be able to apply the whole thing at once. I'll get multiple copies in case it doesn't work out, and to have spare legends for later maintenance. (The actual panel paint is a slightly lighter gray than it appears in this image, at least in my Firefox browser.)

Now I'll take an actual size print out to the hangar, and hold up each device (switch, light, clock, etc.) to make sure there will be enough clearance between the edges and the lettering. I think there will be, but... prudence requires a careful check.

The panel overlays and throttle bracket were delivered to neighbor Mike Payne for painting an hour ago. It will be done in a fairly dark gray PPG DCC two-part paint, with white vinyl transfer lettering on top. As usual, I was dithering until the last possible moment -- about switch locations, LED indicator types/sizes, etc. Kind of like designing (parts of) the panel all over again. Am glad to have all that nailed down, at least the decision part. 

Mike suggested I put the side panels, which have the most lettering, in the scanner, creating an actual size image. I'll attempt to create the overlay template in a few large pieces, working right on actual size digital image. We'll see how that goes.

Meanwhile, the wiring has been coming along, slowly but surely. I had to dig into a few of the D-sub connectors in the wiring harnesses to get at a few things I decided I needed to access after all. I've completed the D-sub for the ARINC module, and EFIS serial ports. There's a natural (?) tendency to want to run wires for merely possible, future, maybe-sort-of accessories merely 'cause it's easier to do it now. The downside is those dark wires may be dead weight for a long time.

At this point, I'm pretty sure I only have about a half dozen more wires to string at which point everything, yes everything will be there. Next step will be to complete untangling the wire bundles, before continuing with many dozens of wire terminations. When the panel pieces get back, all nicely painted, I can get to work on mounting the real goodies (devices) in earnest.

A big day today, with lots of work gradually organizing the routing of wires under the panel, a start on a few going up and over the doors, and finally, the throttle and mixture cables in place for the first time. The mixture cable routes quite nicely to the AeroCarb. The throttle cable may take a little adjustment, but... I'm stoked! (Real seats will be about 2.5" higher.)

The FWF wiring has been really coming along -- probably about 2/3 or more done now. Most everything on the FW itself is done, with the major work remaining being the connections of wiring to engine mounted sensors. The CHT's (6) and EGT's (6) each have two spade lug connections that need to be crimped and, because the wire is "hard" and won't "cold weld" as a normal crimp will do, they have to be individually (24) soldered as well. And all the engine mounted sensor wiring needs heightened protection from heat, of course. At the moment, however, I realized that before I can finally button down wire bundles to the engine mount, I have to get the throttle, mixture, cabin and carb heat cables installed, because they require priority placement of mount points on the engine mount tubing. And THAT means I have to make some more progress on the maze of wires currently hanging down under the panel inside, so there will be room for the control cables.