Jay; I am in the same boat.  I thought about pulluing the overlay off and expose the underlying structure.  Mine is not pretty so some sort or fabrication will have to happen if I do that.

Stan; I will check out what Plane Plastics has to offer.  Thanks!

     Dave

Dave, the part shown on page 17 of the Plane Plastics catalog clearly isn't designed to fit the '56, '57, and '58 172 panels. I've looked at most of the aftermarket manufacturers and can't find a replacement panel overlay for the '56-'58s, which are completely different from the '59s and later.

The Cessna part number for the '56 panel overlay is 0513004-26, and the cessnaparts.com <http://www.cessnaparts.com> website says "Call for availability". Their number is 1-800-998-7832. You might give them a call (I usually talk to Ron) and ask if they're available and if so, at what price. When you ask the price, you should probably be sitting down. :-)

Thanks for your help Stan. Dave, my panel is aluminum and I'm thinking I may do what you suggested. I'll check on the price of the new overlay but I'm not committed to replacing it. I'm thinking of making some upgrades on instrumentation and the original style overlay doesn't lend itself very well to what I may end up with.

Roger,

With all due respect, waterjet is not the most economical way to go. Some by hand and some by CNC milling center is. Also, if you talk with a powder coater, they know within a few mils of the finished coating thickness. In your layout, you compensate for the additional thickness + .005-.01 thousanths.

Paint is a bad idea, unless you intend to remove the panel and repaint it every 6 months. With Powder coat, especally the epoxy based coatings, you can drag your keys over it with force and not damage the finish.

With regard to the layout, it is a fairly easy thing. Get posterboard, scissors, and tape, and start cutting and taping until the exact exterior shape is obtained. In a Cessna, nothing about the outside shape is a true radus, square or paraell line. To transfer from the physical shape to a CAD file is nearly impossible without making several test templates. Even with 3 or so patterns, you wont be happy. Cut the outside shape and cutout for the radios by hand,  by transfering the posterboard template to the aluminum. The instrument holes are easiest obtained by CNC mill, since the some of cutouts are notched for the setting knob. The Aircraft spruce catalog has the dimensions for the standard cutouts.

Also DXF file format is old hat. Industry standard is .IGS (or .IGES) All the CAM software packages can read it. Not so with DXF. Autocad is also old hat.

Lots of great responses to my original post of what to do about old worn plastic panel overlays. I checked with Plane Plastics and I'm not satisfied with what they offer. If I'm unable to find a company that provides a factory type replacment panel I'm considering pulling off all the plastic and exposing the aluminum panel underneath. Now the problem is how to best finish off the exposed aluminum and how to best label everything that requires labeling.

Anyone have suggestions? Would paint work OK? I was thinking about a wrinkle finish look. Do I have to etch the aluminum before painting? Has anyone done this?

Four years ago, I took the plunge and installed an Avion Research <http://www.avion.com> panel in my '63 172D.

"Before" and "after" photos are at <http://home.earthlink.net/~k4drd/index.html>. The panel is STC'd, powdercoated aluminum, and makes the airplane a real joy to fly.