Hi,
I hope I am not butting in here too much, apologies if that is the case.
I used to be a Laser printer expert (for big ones weighing several tons!) but the principles are the same basically for all printers of this type.
To get the tone from the drum, you have to have the opposite charge on the paper than the drum has. The drum has to be positive for some designs and negative for others....it depends on the manufacturer.....
Some have the print character on the drum as an "absence" of charge (rest of drum charged positively or negatively), some have all of the drum except where the characters are as being an "absence" of charge, its almost impossible to say which printer has which without the repair manuals from the manufacturer......
Here is a link which explains one method charge wise:-
http://www.chaminade.org/MIS/Articles/HowLaserPrintersWork.htmYou may need to increase the "transfer" charge voltage to get enough toner directly on the board. Having a board with a metal coating (normal PCB) makes life very difficult for you. I personally think (never tested it!) that an inkjet printer would be a better start for direct printing.......also paper is pliable (and if correctly acclimatised will take a charge quite happily)and will "fit" better against the drum, the PCB is hard, maybe not quite flat and may simply not get near enough to "pick up" the toner correctly.....
Getting laser printers to print on paper is sometimes quite a difficult process......let alone on metal!!
Greetings from
Andy Mathison
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