Construction

Construction Details Finish&Fly Events and Projects Building from Plans Raw Materials Q&A Tools Construction Log

Up
Design
Prototype
Construction
Selection
Finishing
Wiring
Finish Again

 

Step 6: Building the panel

Zenair 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.

There 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.

The 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.

 
Dcp01310.jpg (62415 bytes) 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.
Dcp01311.jpg (55264 bytes) 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.
Dcp01312.jpg (51591 bytes) 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.
Dcp01313.jpg (54228 bytes) A contribution from my kids
I borrowed a stick of glue to apply the template directly on the panel. 
Dcp01316.jpg (51097 bytes) 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.

Dcp01317.jpg (60369 bytes) 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 product.

At least, for the most critical hole (the radio hole), I've done a perfect job.

 

Dcp01319.jpg (61130 bytes) Job done... 

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.

Dcp01320.jpg (60585 bytes) 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! :-)

Dcp01321.jpg (52971 bytes) One good day
Ah!  You couldn't imagine the excitement as I finished this and put some of the gadgets for fun. 

 

Dcp01322.jpg (54956 bytes) 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 here.

I may install the altitude encoder underneath later as I progress on the installation.

Dcp01323.jpg (56244 bytes) There it is!
Dcp01405.jpg (76526 bytes) 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.
Dcp01416.jpg (86226 bytes) 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.

 

 

Home ] Up ] Construction Details ] Finish&Fly ] Events and Projects ] Building from Plans ] Raw Materials ] Q&A ] Tools ] Construction Log ]
e-Mail me at mtherr@yahoo.com

Counter reset on August 10, 2000 (4302 visits on main page prior to reset)
Michel Therrien, (c) 1999 - 2003.