Techniques for home made backlight panels and annunciators
Since Level D released the 767 for FSX, I'm building a 767 simulator. There's very limited supply of 767 panels, especially overheads. I don't know of any company that makes them in fact.
So I'm messing around on my own to see how effective I can get, charged only with sheets of plexiglass, an inkjet and laser printer, and a tolerant and forgiving wife.
For the first prototype I used some Letter sized adhesive clear labels and printed using a laser printer. As expected the opacity was not up to scratch so I had to double up the labels. This caused major issues as it's near to impossible to accurately align each label before committing them to each other for ever. A slight offset (which is the best I got) makes the legends and graphics appear blurred. Also, laser printers use a halftone screen for colour, and this technically means there's holes in the print, making light bleed an issue.
I decided to try the same again, but this time have a black layer and then an identical coloured layer on top. The light blocking was more effective, but because of the bleed from the colour layer, the panel appeared practically black until backlit. Well I can live with that! But it's still not a satisfactory process.
So I've gone away to think about this a bit. The problem is that I'm using adhesive labels so aligning (or registering) the layers is a royal pain. To get good light filtering, I'm going to need probably 3-4 layers. But the chances of getting 3 layers in acceptable alignment is almost zero with sticky labels. However, I'm now thinking of trying inkjet/laser printable acetate sheets, and inkjet printing them instead of laser.
Being non adhesive, I can print and align the images by hand, and even when adhesive has been applied, they can be shifted into position. I am guess that I'll need 4 layers for lighter background colours, and 3 for black (like for annunciators). Also I figured instead of printing the colour of the annunciator light direct onto the acetate it would be best to leave this clera and rely on having the right LED colour to create this effect. This is because I'll get more pure light at the right colour, instead of a hotspot or too dim illumination, depending on the opacity of the acetate.
So that's my situation. Anyone have any advice, or has tried this method? I heard someone say they got a load of annunciator legends professionally printed on Lexan which gave great light blocking. I will look into the same, although the assembly is not too different. For Ink Jet acetates I have a clear spray that I've tried before. It doesn't cause the ink to run, and provides a gloss finish, and protects the annunciators from smudging (not that you touch them much).
Looking forward to your thoughts, as ever.
Paul
