A nifty method for generating artwork for prototype pc boards uses an ornamental foil originally made to simply dress-up printouts. To use LaserColor foil (Minds In Motion, PO Box 679, Lindhurst, NJ 07071), first draw the artwork, positive or negative, using any drawing program. Whatever is black on the printout becomes opaque on the finished artwork.

Next, using a laser printer, print your artwork onto a clear, transparent film. Next, cut a piece of the LaserColor foil and lay it over the artwork, tacking it in place with the little sticky dots supplied. Last, run the sheets through the laser printer again (form feed).

When the film passes over the drum inside the printer, the foil sinters onto those areas of the film that are covered with toner. When you peel over the extra foil, you have artwork suitable for photoetching a pc board.

At least one product similar to LaserFoil is on the market. But the advantage of LaserFoil is that you need to use a piece of foil only as large as the artwork; the other method requires feeding a whole sheet through at a time.

The foil’s real purpose is being applied to paper to dress up reports. The foil behaves differently when you try to apply it to clear film. You have to experiment to get consistent results. The most important factor is the type of clear film on which you are printing. Don’t use the standard overhead-transparency film because it causes the toner to become blotchy and thin. You need a dense coating if the foil is to adhere really well.

A sticky-backed film, such as Rayven 320 (Rayven Inc, 431 N Griggs St, St Paul, MN 55104), is a little cloudier than the overhead-projector film, but the toner takes to it very well. You have to apply the sticky-backed film to a sheet of clear film to keep it from sticking to the innards of your printer. Luckily, overhead-transparency film works great for this application.

Also, as with any other photographic artwork, you get better results if you print a mirror image so that the foil is against the pc board when the board is being developed. This orientation keeps the light from diffracting through the film around the foil and etching away more copper than you intend. (DI #1418)