Step 4: Prototype it

My first prototype was done using the instrument panel bulkhead with some pieces of aluminum to simulate the sub panels.  This was done before finalizing the draft drawings.

One I was fairly happy with the design (around my version 7 of the 23 versions I had), I transferred the drawing on paper.  I don't have a plotter, so I printed out the panel on multiple pages using my Deskjet printer and I attached the several sheets together.

To accomplish this, I used a game table that my kids have in the play room and I borrowed one of our bedroom windows (!).  I installed some lights in the play table under the window so I could match the lines of the panel together.

I tested many configurations.  While the panel configuration did not changed a lot, I did move things around a little bit.  For instance, I worked a lot for positioning the vents and the phone jacks.  I decided to go with a 2-1/4" transponder when they will be available (Becker USA and MicroAir both have such units that should be available... one year ago).

I moved my fuel gauges to the sub panel. And while designing the panel, I must admit that I also did a lot of electrical system design (but it's all in my head now).  For instance, I intend to have a dual battery, single alternator setup as described in Aeroelectric's Connection book. (oh! this is a great book to buy, by the way).  However, I intend to make the handling of problem situation simpler.   I want to deactivate the battery contactors and activate the aux feed to the essential bus with one switch (no time for diagnostic and operating three switches when things go wrong).

The other thing that I should have noticed with my prototype, but I guess, I was blindfolded by my excitement of the layout, is that the shape of the panel as per plans 3rd edition is wrong.  I want to have a forward tilting canopy and ZAC modified the instrument panel shape, rising each side about 10 or 15mm.  The 4th edition of the plans include that change but there is one mistake in the coordinates.  The second coordinate from the center line shoudl be spaced 100mm, not 126 mm (the first is as 126mm from CL and the second 100mm away from the first one).

In my case, I realized that only after I formed the actual panel, installed the stiffeners and tried to figure out how I would position the canopy tube frame.

Step 5: Finalize the drawing