Ed,

 

>>I've been drilling holes in the Lancair supplied Fiberglass Instrument Panel
>>for my 235 (switches/lights/breakers etc.) and I'm having a tough time getting
>>good clean holes.  Most holes have delamination around the hole on the
>>backside of the panel. 

 

I submit that because of the course weave of the fiberglass, the type of resin used, and the layup method (gel coat on the front side) of the 235 panels, drilling through the panel will always leave a frayed rough fiberglass cloth finish on the back side as the drill cuts through, so the panel backside glass will need to be touched up with sandpaper.

 

>>You can make a much nicer looking panel and with today's
>>radios, you don't need that center bulge to accomodate the long radios of
>>yesteryear.

 

The 235 header tank is larger than and of a different shape (L-shape) than the 320/360 header tank.  So, most likely you will need that center bulge to have enough room for the radio stack.  Including the wiring harness connection with antenna leads, and considering the header tank fuel inlets and vent line outlets, there isn't much room left over (taking into consideration a King KX-155 NavCom and Apollo 2001 GPS).  And that is with the panel in the vertical position.  If the panel is tilted slightly for the tall pilots, there is even less room between the radios and the header tank.

 

>>An even better idea is to make your panel out
>>of aluminium.

 

There is likely going to less available room on the already small 235 panel when using metal panels than leaving the fiberglass in place.  Leaving some fiberglass material around the cutout to mount the nut plates for the metal panel inserts will limit the usable area.  Some of the items on my all glass panel are mounted very near the edge. (ie, the traditional 6 flight instruments are mounted at the very bottom of the panel and at the extreme edge the the radio stack line to get enough clearance at the top to close the canopy)   

 

Gary Edwards

LNC2 N21SN

235/320