Mike Powell

Just about everything has been done that you mention. There's an Arduino-based approach being discussed over at MyCockpit for FSX http://www.mycockpit.org/forums/showthread.php/22636-Arduino-COM-NAV-LED-display-FSX Here's a totally DIY, micro controller based approach on my site: http://www.mikesflightdeck.com/oldnews/oldnews_2007.html (Scroll down to the March 22, 2007 entry.) And another, DIY, but very realistic approach on Viperpits: http://www.viperpits.org/smf/index.php?topic=5082.0

I need to make the perimeter pieces now. They have bends in them and might be a bit more difficult than the pieces so far.

This is more time consuming than I expected, but it's beginning to look real.

Well, I got the house projects under control, the aluminum arrived, and I was able to get the majority of the pieces cut. I expect to start building the frame tomorrow.

Sounds interesting, but here are a couple of thoughts. White LEDs don't necessarily have a smooth spectrum. Depending on how they are made they may have only a few well defined spectral peaks that the human eye experiences in aggregate as white. Putting a color filter on such a light source may not leave you with what you expect. You might be better off finding a green LED with a wavelength meeting (or close to) the NVIS spec. A perhaps simpler approach to making the light plates is to use a single layer of "lighting white" translucent acrylic. Give it two coats of reflective white then two or three coats of black. Engrave through the paint layers. Mount the LEDs in holes in the aluminum backplate such that the LEDs protrude into partial holes in the acrylic. Use wide angle or edge-lighting LEDs. I've had good luck with this approach lighting instrument faceplates. I size the mounting hole to fit the LED body, but not the LED shoulder. I use a drop of epoxy over the back of the LED.

I was looking at that model as well. I'll be interested in how it turns out.

Looks very good.

Check out http://www.strandedduckling.com/html/instrumentpanel.html for measurements of an A-10A MIP frame.

Thank you. The aluminum I ordered is scheduled for delivery this coming Monday. I have some house projects to work on as well, but should begin making progress on the MIP structure next week even if it's slow.

I made a few refinements, and ordered some aluminum. What surprised me is that it's far cheaper to order from Onlinemetals in Seattle than it is to buy the stuff from a local home building supply store. Including shipping and additional material for jigging the pieces while the epoxy cures, I've spent only $65 so far. I still have to buy the threaded spacers and a chunk of ply or MDF for a work surface.

I built a two cell lattice to test the epoxy and aluminum bar MIP structure concept. One cell is for a round body 3.25" instrument while the other is for a square body instrument. The mounting holes for the square body instrument are so close to the corners that I had to slightly file the threaded spacers to get them to fit properly. The holes for the round body instrument are far enough from the corners that I could add aluminum angle which substantially increased the strength of the lattice. (I didn't bother adding spacers to this cell as I had already tested that in the other cell.) The positions of most mounting holes for instruments and sub-panels in the A-10C MIP leave enough room for adding 1/16" x 1/2" x 1/2" angle to each corner. I will probably do so. I can't break the test piece bare handed, though If I jumped on it at the right angle I probably could. In any case, the concept seems a good one which I expect will scale nicely to full MIP proportions.

Thanks!

Y2kiah, thanks. I'll look into the 8020 material. The threaded spacers I'm thinking of using are an inch long. I was considering using some sort of metal gusset for the bar elements wider than an inch. Also thanks for the LCD information. I will be looking more closely at MFCD options before I start building. I need to find an accurate drawing of the real MFCD. What I have currently is a drawing of the smaller F-16 MFD. Avilator, to hold the threaded spacers I'll use a hole template with the spacers mounted on it. The assembly work will progress in small stages. I'll use just enough epoxy to hold the bars in place for one or two openings. Once they are stable, I position the template with the spacers for an opening and epoxy them in place. It will be a slow process.

Looking good.

I've been considering how I might build the panel support structure for an A-10C MIP. Since the real structure is essentially a lattice of bars, I'm looking very closely at using aluminum bar stock. My goal is to create a design that closely follows the dimensions of the real MIP, but is adapted to using slightly oversized displays for the MFCDs. I started by developing a drawing which combined the required panel cutouts for all the instruments and subpanels. For each element I added an orange dimension representing the depth of the structure for that area. I then boxed in each area with virtual 0.125" bars of a width equal to that depth. That gave me a 3d rendering of the resulting lattice structure. All in all, I figure it's not too shabby, though clearly it's distorted relative to the real panel structure to accommodate the larger MFCD displays. For this design iteration I'm using a 8" LCD monitor with 800 x 600 resolution. I may move away from this choice, but the next smaller size falls far short, so maybe not. I'm about to test the suitability of epoxy for holding this together. I've had good success using epoxy and steel structures. The trick has been to assure that the load tends to push joints together and that the epoxy adds stability rather than taking the full load. That's won't be possible with all the joints here, but I think I will have enough long pieces passing through notches in others such that the overall structure will be quite strong. I've used filled epoxies like JB Weld and PC17 putty to good effect to build substantial fillets that gusset the joint. I'll do the same here, plus I'll embed an internally threaded metal spacer to provide attachment points for the instruments and subpanels. My next step is making a proof of concept prototype which supports one or two instruments.

It should work. The higher minimum resistance can be compensated for by scaling up the resistances around the opamp. It's an issue of accuracy. Ideally you'd have the stage provide a gain of +1.000 or of -1.000. Too high an on resistance will reduce the inverting gain. The FET forms a voltage divider with the 10K resistor. The ratio of those two resistances is a key accuracy factor. However, given tolerances of other components, you'll likely not see a problem. The 13-bit precision of the circuitry was developed to produce a smoothly varying output rather than a strictly 13-bit accuracy.

Looking good.

I'm interested in anything you might care to post. Straight-on (i.e. limited perspective distortion) high res pictures of each would be very helpful and much appreciated. The overall backing plate dimensions also. Heighth in particular, as I believe the width of each is 5.75". The pictures you have already posted have been helpful. Thanks!

Mil standard MS25212 is a one page drawing that details common dimensions for panels. You should be able download it using this link: http://www.everyspec.com/MS+Specs/MS2/MS25000-MS25999/download.php?spec=MS25212C.008526.PDF If you'd like to know about the rails these units fasten to in aircraft, take a look at MS25213 http://www.everyspec.com/MS+Specs/MS2/MS25000-MS25999/download.php?spec=MS25213B.008527.PDF If you'd like to know about the "DZUS" fasteners, see MIL-F-25173 http://www.everyspec.com/MIL-SPECS/MIL+SPECS+(MIL-F)/download.php?spec=MIL-F-25173A.015077.PDF "DZUS" quarter turn fasteners aren't made by the DZUS company. They are made by DFCI Solutions www.dfcis.com and are part of their PA-3500 product line. A guy named Dzus developed them a long time ago, but lost the "DZUS" product trade name. If you're interested in light plates, see MIL-P-7788 http://www.everyspec.com/MIL-SPECS/MIL+SPECS+(MIL-P)/download.php?spec=MIL-P-7788F.026180.pdf

Colin, thanks for the kind words. Pete, currently I have an abandoned 206B project and no room, but I have hopes.

In my current situation, (retired, incredibly lazy, and living in a small house made even more cramped by adult children moving back in), I can't see myself making stuff for sale. However, if there is continuing interest, I will probably continue to publish books about flight sim. Almost certainly, these sorts of projects would be included. Design files for PC boards and hex files for microcontrollers would be posted on a support page. [i suppose books qualify as "stuff", but I don't actually make them. I just write them. I get a printing company to make them and ship them to me so my garage becomes even more cluttered.]

Periodically I sit alone in a corner and play with magnets. The most recent such occurance has resulted in DIY air-core movement. Why? Well, because I can, and because the air-core is small enough to make a 1" diameter gauge and strong enough to spin a pointer in a 3 inch gauge. Besides, magnets are just neat! The rotor in this movement is a 5mm diameter neodymium tubular magnet mounted on a bit of 0.035 stainless steel wire. The bearing which supports the rotor shaft is a half inch of 1/16" diameter brass tubing which I enlarged very slightly with a 0.85mm drill bit. This tubing is held concentric with respect to the movement body, a piece of 1/4" diameter brass tubing. Once this was sealed, I glued four wire guides to support the two field windings. The cylinder to the left is chunk of 3/4" thin wall electrical conduit which serves as a magnetic shield, and protection for the thin field wires. Each winding consists of 600 turns of #38 enameled wire. The movement works well when driven by 5 volts on the windings. I built a PIC16F648A controller to drive it using pulse width modulation. The controller accepts commands across an RS-485 shared instrument bus. The board on the left is the RS-232 to RS-485 adapter which hangs off the computer's serial com port. Works great.

Cuts made with circular saws and jigsaws can be quite accurate. The trick isn't having super human control of the tool. It's planning that minimizes the need for super precision, accurate layout and marking, and using guides when making the cuts. I vote for "C".

Nicely done!

Sounds like an old style tachometer with a permanent magnet three pahse synchronous motor coupled to a magnetic drag plate or cup. These tachs were feed by a tach generator which was really a three phase alternator.