On 1/11/02 at 6:59 PM Dexter wrote: >> I know Stuart Honeyball produced some commercial boards but printing >> direct onto special film. >> It apparently worked very well, but there is loss of quality. No chance >> of .5mm romdisq type pitches by this method.
>The loss of quality is because you need to reverse the image in the X and >Y planes. Actually, you need to this even on large geometry PCBs because the etch quality is better. Ultimately, there is difraction along the edges in the photo resist itself, which is the biggest limit to the track width. However, there is a method that uses transfer paper and actually transfers the toner directly onto the copper, usually it involves an iron. This would be much better if one could have a hot roller, for instance out of an old photocopier. Unfortunately, it is the uniformity of toner deposition, entirely a matter of the printer used, that limits the quality achieved with this method. Nasta
