My Cessna Sim Project

My Cessna Sim Project
To visit my project web site click on the image above or go to: www.mycessnasim.info

Sunday, November 20, 2011

A lot of sub assembly work done, but no big pieces.
To allow me to build several of the wire harnesses outside the cockpit I built a nail board, a full scale mock up of the instrument panel and part of the firewall with finish nails used as wire guides and termination points.  I have about 1/2 of the instrument panel switch wiring done, about 200' of wire.  This wire harness will be installed after I get all the lower panel switches installed.  Because I installed my  BU0836A on a mounting
board with terminal strips I was able to terminate the harness on it and this allowed me to test each connection through to FSX as I progressed.  The next two USB encoder cards I purchase will be the newer BU0836X cards and those will be mounted on the cockpit side of the fire wall.  Those will pick up the switches and pots in the center console to include the 3 trims, the cowl flaps, fuel selector valve, and others.  The density of the wiring in this area makes this approach ideal.  For other sections I won't likely use a nail board.  Instead they will be wired in place or use small free hand wire harnesses.

The next small sub assembly started was the engine controls, throttle, prop, and mixture.  Although just started and I still need to order the potentiometers and design a mounting bracket for each.  Those will be part of the mix in my next round of material purchases.  I also need to find the large fine thread nuts needed to mount the controls in the instrument panel, I have one so far out of the three needed.  These controls are cut down from actual Cessna cables I found on eBay.   Each cable sheath was removed and the cable core left long enough to use the full travel of a 100mm slide pot.

The one piece of heavy lifting this weekend came while making a temporary under carriage for the fuselage.  It came out well enough that I may decide to add a mid support and finish it in back as the permanent under
carriage.  The rear mounts took advantage of the existing landing gear supports in the fuselage.  Having machinists in the family is a great thing.  I had two 12" long 1 7/8" diameter aluminum shafts made to press fit into the landing gear mounts.  Each had the ends drilled out and threaded to receive a 1/2" bolt.  My original idea was to fabricate a steel under carriage that these would bolt to, but as I said, my temporary wood frame is coming out good enough that I might consider keeping it.  If I do I'll add one more set of mounting points using the attach points from the wing struts witch I previously removed.  With the two additional casters the weight should be well distributed and the fuselage stable even with both seats occupied.  Of course, I'll have to paint it as well.

Here are a couple pics of the mounting shaft and the mounting frame installed.  Each shaft end had to be tapered and then hammered in.  The temporary mounting frame is made up of 2"x10" lumber glued and lag bolted together.  It's made such that the landing gear mounting bars drop in and are bolted from the ends.  In the event that I have to access the underside of the fuselage the mounts also allow for it to be tipped up.  Hopefully a rare event, but I did cut some rather large access holes on the underside to install some of the rudder linkage and may also need to      
access it again when I install the elevator centering springs and position sensor.  After that I'm hoping not to have much need for that feature.  I also have the undercarriage up on 3" swivel casters to make it easy to move around during the build.  Those will most likely come off when the fuselage is positioned in front of the projection screen.  As can also be seen in the pics I have the rear bulkhead in place.  I'll be mounting surround left and right rear speakers through it and either through or on it inside a surround sub-woofer.  The interior surface will be covered in carpet and the exterior will have a cover made and held on with thumb screws of some type.  Another idea I am looking at will be to mount a web cam on the interior of the bulkhead to allow for over the shoulder video during flight.

Well, that's what I've been up to for the past few weeks now.  I'm hoping to get some more work done over the Thanksgiving holiday to include installing the lower switch panel.  Very early in December I'm planning to order the hardware I need to fabricate the elevator, aileron,and rudder linkages and position sensors.  I'm going to try and get those linkages built and get the position sensors hooked up and tested before Christmas.  After that I'll install the yokes, the cowl deck cover and the glare shield.  If all goes well I'll be ready for the windshield install in the January or February time frame.  After that, maybe in the Feb/Mar time frame I'll be able to design and fabricate the end caps that will enclose where the wings were previously installed.

So now I've put some of the near term plans in writing in the hope that I can hold myself accountable to the plan I just published.  I may have to slip things a month for budget reasons but I hope not much more than that.  That's all for now . . .

 HAPPY THANKSGIVING!!!

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