10-07-2021, 02:44 PM
For those of you who still homebrew PCBs :
I have had issues printing transparencies for use with positive resist PCB for a while now, ink smearing etc, despite using materials that are one side for laser/other side for inkjet. Swapping from Epson to 3rd party ink cartridges turned out a little better but finally the print head clogged up through lack of use. Nothing chemical seemed to clear the head so it was time for another printer.
The replacement is an Epson 2100 series inkjet and using original Epson cartridges produced yet more smears or 'spotty' prints on the original film materials. The ink just did not stick well to the rough side of the transparency material, and was certainly far from 'black enough'. Note the settings were A4, Epson Matte, greyscale etc - all as used successfully previously (at least until Epson seemingly changed their ink chemistry).
The solution was found to be : EZIscreen A4 Artwork Transparency Film - Pack 20 | Inkjet/ Hand Drawn/ Laser | Professional Grade | Coated Waterproof Film
available from https://www.screenprintingshop.com.au/
So still using the same printer settings (i.e. as above) and the printer-supplied Epson OEM cartridges, out came a perfectly black artwork - no smears or spots - using this new film.
Printing a PCB produced a perfect result with tracks between SMD SOIC pads and through 0805 parts pads having good clearance and no 'furries' visible.
The positive photo board being used at the moment is RS Components 164-0550 by Fortex for single-sided and 164-0555 for double-sided layouts, exposure at 45 seconds of full sunlight in a contact print frame assembly.
Developer is a weak-ish warmed-up sodium hydroxide solution ('caustic soda') followed by an agitated medium-heat ferric chloride bath etchant.
Hopefully this will help those still wielding a soldering iron on those homebrew PCBs !!
I have had issues printing transparencies for use with positive resist PCB for a while now, ink smearing etc, despite using materials that are one side for laser/other side for inkjet. Swapping from Epson to 3rd party ink cartridges turned out a little better but finally the print head clogged up through lack of use. Nothing chemical seemed to clear the head so it was time for another printer.
The replacement is an Epson 2100 series inkjet and using original Epson cartridges produced yet more smears or 'spotty' prints on the original film materials. The ink just did not stick well to the rough side of the transparency material, and was certainly far from 'black enough'. Note the settings were A4, Epson Matte, greyscale etc - all as used successfully previously (at least until Epson seemingly changed their ink chemistry).
The solution was found to be : EZIscreen A4 Artwork Transparency Film - Pack 20 | Inkjet/ Hand Drawn/ Laser | Professional Grade | Coated Waterproof Film
available from https://www.screenprintingshop.com.au/
So still using the same printer settings (i.e. as above) and the printer-supplied Epson OEM cartridges, out came a perfectly black artwork - no smears or spots - using this new film.
Printing a PCB produced a perfect result with tracks between SMD SOIC pads and through 0805 parts pads having good clearance and no 'furries' visible.
The positive photo board being used at the moment is RS Components 164-0550 by Fortex for single-sided and 164-0555 for double-sided layouts, exposure at 45 seconds of full sunlight in a contact print frame assembly.
Developer is a weak-ish warmed-up sodium hydroxide solution ('caustic soda') followed by an agitated medium-heat ferric chloride bath etchant.
Hopefully this will help those still wielding a soldering iron on those homebrew PCBs !!