jackinnj said:I think that the easiest and best way is with the photo-sensitive PCB material. I can get trace width of 8 mils repeatedly. I print to over-head transparency material, expose on a photographic light-box, develop in dilute NaOH and etch in a cocktail of H2O2 and HCl.
There's a very good PCB user group on Yahoo --
I have done small PCB's with non-photosensitive material directly on an HP7475A plotter. Anything greater than about 4 square inches has too much mass to use a plotter. You can then trance over the plotted lines with a waterproof sharpie.
davidallancole said:Minion, have you found that the 2 parts hydrogen Peroxide with 1 part muriotic acid needs to be heated 10-20 degrees above room temperature to make it work good? I found that it was utterly slow at room temperature.
Use the high speed steel bits and throw them out when they get dull.sandstorm33 said:But then come the FUN!!!..Drilling the result. I have trouble keeping the small carbide drill bits from breaking .....Anybody got a system for successful drilling???
Agus Widarto said:Just Now I found from web site make PCB with Positive 20. can you tell me about Positive 20 ? this a brand merk or name of chemical..
Thank! for all your replay.
originally posted by justblair
I find that it is much better to use this spray than to buy the presensitised boards. The spray is a lot more forgiving on bad negatives and poor exposure times.