Dan wrote:
cavelamb wrote:
Dan wrote:
cavelamb wrote:
Dan wrote:
cavelamb wrote:
I remember Linda Rice's Lockheed had a really cool backlit panel
overlay.
The panel itself was heavy aluminum sheet, but then they added a
plastic
overlay that had an opaque cover. Legends and labeling was done by
engraving the opaque layer.

On the back side of the there were little cavities carved for
grain of rice (well duh!) light bulbs.

The effect was quite stunning.

So does anybody know where to find this kind of plastic for the
overlay?


Thanks,

Richard


I use white plexiglass. Paint the face and edges black and have
it engraved or engrave it then use a roller to paint the face and
sides.

Dan, U.S. Air Force, retired


Ok, so other than good intentions and great karma, what kept the paint
out of the lettering?

If you paint it before engraving you won't have that problem. Using
a roller to paint after you engrave means very little, if any paint
gets into the lettering. I used a rubber roller like engravers use. I
prefer the paint first method, but sometimes you need to repaint
after adding engraving or damaged paint.

I might mention painting the back of the plastic prevents light leaks.

For the truly patient/crazy you can route grooves in the back for
wiring. The number of lights required depends on the size of the
panel and embedded wiring means you only have 2 wires hanging out the
back.

Military/commercial lighted panels have a little coaxial connector
on the back that presses into a socket when you mount the panel. If
you ever see one of this type of panel you'll notice a little plus
sign on the front. The connector is directly behind it. Should
lighting fail you can press there to see if the connection is bad.
Older panels had light assemblies that screwed through the panel from
the front.

Dan, U.S. Air Force, retired

Thanks, Dan.
That's a possibility.

The comm shops in USAF units was authorized an engraver for intercom
boxes face plates since the boxes had a bunch of pull-on volume controls
and had to be re-labeled for the specific location on the aircraft or
specific aircraft. Guess what? They just swapped out face plates when
replacing the boxes.

Another option you might try is the black on white plastic
trophy/engraving shops use for name plates. Granted it's thinner than
the plates we used which were 3/8" thick or so. I suppose an annunciator
light or illuminated tail number plate can be made if you make a bezel
to hold it with the lamps behind.

You might also consider LED instead of incandescent.

Dan, U.S. Air Force, retired

Yeah, I remember fondly the side panels with all the cool military toys.
Boy, those were the days.

LED already considered. And approved, of course!

One design flaw so far is isolating some areas so that annunciators
don't bleed over into the rest of the panel.

I think that problem can be addressed by milling out the back plastic
but leaving an overlay but obviously won't work with a painted panel.

That's kinda why I was thinking of a thin plastic overlay.

The back-light panel can then be pieced together as needed but still
present a smooth unbroken surface.

I'm guessing something .008 to .016 thick(?) for readability of the
engraved parts.