Step 6: Building the panel
calls for a simple panel made of 0.025" aluminum. On the Zenair
panel, there are fuel tank supports installed on each side that also act
as stiffeners. Many builders commented that the panel is somewhat
floppy, especially if you install many instruments and radios.
are various approaches to solve this. Some kit builders add an
overlay to the instrument panel. Often, a sheet of 0.040" is
added to the 0.025" panel.
I decided to make the panel
with a sheet of 0.032". This will be a lot stiffer than the
0.025" panel and much lighter than some other ways of addressing the
issue. At the bottom, instead of bending the 0.032" sheet, I
decided to rivet two L stiffeners on top of each other (giving a
0.050" stiffener). This appears to be rigid enough.
six flight instruments will be mounted on a sub-panel made of 0.064"
aluminum which will be mounted to the main panel with shock absorbers.
||I really want a nice cut
I don't have a shear and the best way I know to make a really
nice, clean, square cut is to use a router. That's what I did
for the bottom of the panel.
||It' getting cold.
I normally do not open the garage door while working on the plane in
the winter. But I had no choice because my vise is right next
to the door... Here I am hammering the panel 0.032 sheet on
the forming bloc that I made.
||The bottom stiffener being installed
As I mentioned, I installed two L stiffeners stacked together at the
bottom of the panel. This picture is of my first panel that I
trashed after I found out the sides were not high enough to accommodate
the forward tilting canopy tube frame.
||A contribution from my kids
I borrowed a stick of glue to apply the template directly on the
||And some non-precision, precise drilling
I don't own a machine shop with CNC milling or laser cutting
technology. I drilled all the pilot holes using this bit (I
don't know how it's called) on my press drill.
Each instrument hole has a cross identifying its center. I
also drawn location marks inside each square corner so I can
precisely drill the relief holes.
||Cutting some of those square holes
For the smaller square holes, I used my Dremel. I did succeed
to exceed the required dimensions sometimes, obliging me to move my
corner relief... but these mistakes won't show up on the final
At least, for the most critical hole (the radio hole), I've done
a perfect job.
Here are the tools I used for working on this panel. The
larger square holes were cut using the knife and SS ruler. Not
shown is the fly-cutter I used for the instrument holes.
I would like to take this opportunity for a warning. If you
install the EIS from Grand Rapid, DON'T TRUST the dimensions'
diagram!. My four attachment screw holes were mis-positioned
and I found a way to make something acceptable using nutplates.
||Removing the paper is the big thing
I believe I spent more time removing the paper than drilling the
holes! I tried Lacquer thinner, Acetone, Lighter's gas and
other products. Nothing works well although the Lacquer
thinner was a bit better than the other products.
I found the right way to do this only at the very end when I had
some tough paper on the instrument's sub panel. I tried under
hot water... and it worked!!! So, if you ever do this, try hot
water first! :-)
||One good day
Ah! You couldn't imagine the excitement as I finished this
and put some of the gadgets for fun.
||Holding the radio
I notice some much more heavy duty racks from other builders.
I figured that this simple one made with 0.025" aluminum sheet
should be strong enough to hold the whole 2.1lbs of radio I have
I may install the altitude encoder underneath later as I progress
on the installation.
||There it is!
||My instrument sub-panel
It includes the master, the ignition, fuel pump, aux ignition, aux
power feed and bat test switches. There is also an
intercom/speaker switch, two 12V outlet and a VHF antenna
connector. Finally, I have the two fuel gauges.
||Electrical stuff and phone jacks
Following beliefs of Bob Nuckolls in AeroElectrics Connection
and installation examples from other builders (Jeff Small and Fred
Hulen), I decided to mount my fuse panel on an hinged
sub-panel. This will provide fairly access to most circuit
protection devices while freeing up the already limited panel space.
Having decided to install the phone jacks on each side (at design
and prototyping stages), I looked for a simple yet structurally
sound approach to make this happen. I then decided to adapt
little electronic assembly boxes for the purpose. They are
riveted to the cabin side with three rivets. Connections will
be easy to maintain as the cover is removable.