how dark must a photomask be?
2007-10-20 by halfintegerspin
I tried photo resist. I sprayed the board myself using 'positiv 20' and left it to cure for a few days. I printed a few masks on transparency with a laserjet. The masks were all quite transparent. I can hold them up to the screen of my laptop and read thru them? I didn't think it would be any good but I tried it with 3 minutes of UV and the results were pretty good. I didn't bother with exposure tests or testing the developer as the mask and board didn't look very good... I had a new toner in the laserjet, the density set to max[5], resolution on max, fuser temp normal. the transparency is something like hp3770 meant for color laserjet,[mine is an old 4000 monochrome]. I use the laserjet config program to set the density as xp overrides the settings otherwise.. I also did a toner transfer version of the board, the toner trasfer came out perfect;-) richard