Kit Building: The Panel
As I moved into panel construction and wiring, I decided to go a bit beyond the standard panel seen in most Challengers. The standard panel is more than adequate for any and all flying, and is very light (no point adding weight if you don't need to). But somewhere in my past I studied electrical engineering and am a computer buff, so anything less than a state-of-the-art glass panel just wouldn't do!
C-ILHC's Panel - So Far
Here with her basic(!) instrumentation - a 3-Axis gyro enabled, full-colour, Electronic Flight Information System (EFIS) with a moving map GPS. The "steam gauges" are backups! I thought about using smaller 2.25" gauges for backups, but they just aren't as pretty as the stock 3 1/8" gauges that come with the Challenger. By the way, the Enigma EFIS includes several dozen instruments, and weighs less than the analog Altimeter alone! You can read more about the Enigma here: Accessories.
Here are some shots of a few of the default pages that come
with the Enigma.
And the Enigma from the Rear - Just look at all those ports! Even has a GPS, Angle of Attack, Ultra sensitive VSI, etc. and weighs less than the stock altimeter.
A dab of silicone on each switch will keep all the switches aligned straight up and down once all the wiring is done.
Here's the Ultra XL - predecessor to the Enigma. They are
the same size.
I am working feverishly on my panel and wiring and will put more photos up here as I progress.
All my switches and controls are going on the bar underneath. Each is fused with sub-miniature circuit breakers. Here is the lower panel being drilled ... I used a milling machine because I had one, but a drill press will work fine. Just be sure the vise is well clamped to the table - thin aluminum tends to grab drill bits as they break through and then you and the work go spinning! If you line the vise up nice and square, you can just slide the work back and forth along the edge of the vise, making sure to clamp it for each hole of course. You'll need to make a small block of wood just the right size to slide inside the lower panel so as not to crush it with the vice. I used step blocks for the operation on the mill.
Always drill a small hole first and work up in increments of a 1/16" or 1/8" if you'd like to end up with something approximating a round hole of appropriate size.
My switches and circuit breakers worked out just right at 3/4" (0.750") on centre. Switches generally need a 15/32" hole , and the circuit breakers I was using needed a 5/8" hole. The layout work takes a bit of time, but makes the drilling very easy. I used the X-Y table on the mill of course, so the lines where just for reference. If you look real close, you'll see that this drill bit is cutting a 1/32" increment, and that's it. That is how a tool maker friend of mine taught me to drill a round hole. You can use a slot drill (two-flute end mill) or a reamer to, but I didn't have a slot drill the right size the day I was drilling this! Besides, can you think of a better way to spend an afternoon than showing your 12 year old how to run a milling machine by drilling a BUNCH of holes in 1/16" and 1/32" increments?
Here's everything plugged in for a test fit.
Most of the toggles (the SPST On-Off variety) I ended up getting at Canadian Tire! The electronic shops seemed to carry only a few of each variety and I needed an armful of identical switches. The C-Tire ones were cheaper and higher amperage ratings as well. Funny enough, same manufacturer as the more expensive ones.
For the Skis only, I used SPDT On-Off-On switches. Microswitches in the ski mechanism limit the travel. Notice the cute little re-settable breakers right under the switches, and room for a label in between. I will be installing plug-in jacks in the side of the fuselage for the skis to plug into to get power when they're installed. The plugs will have water tight plugs when the skis are off.
Here is the list of items currently installed (left to right):
- 12 Volt Plug in
- Strobe Light Toggle (SPST On-Off) and Circuit Breaker
- Transponder Toggle (SPST On-Off) and Circuit Breaker
- Left and Right MagnetoToggles (SPST On-Off)
- I'll be installing a 3.5mm stereo plug to connect an IPOD easily into the intercom system.
Hinged Aluminum Panel Blanks
I was at about the point of starting to rough out a panel in marine plywood when I was visiting another builder and a Challenger he was just completing for one of our customers. I was impressed by the hinged aluminum panel he had built. The gauge layout and everything were nice, but what I really liked was the aluminum panel itself. It was hinged and fit like a glove. A few questions later and I learned that he had not only built this panel, but he and a friend had the whole works in a CAD program and could CNC cut me one in no time!
These gorgeous CNC machined blanks are now available from ChallengerWest for our customers. The panel folds down with the simple removal of two screws and allows access to the back of the panel. Our supplier can CNC cut your panel to your specs with a CAD layout. Here's an example of a beautiful finished panel with analogue gauges and a nice VHF Radio underneath (the same size and spot as the transponder that's going in C-ILHC).
These blank panels are about $200 complete. If you want holes cut for gauges, CNC cutting costs vary with complexity. A nice standard layout like the one above is available pre-cut to fit standard Challenger instruments for about $400.
The Fine Print - Caution
Ideas, illustrations and photos are the author's own
work and are for information only.