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Hi everyone

I've been experimenting with methods of applying etch resist with a laser and dry film. The process is kind of arduous and error prone.

Developing with sodium carbonate solution to clear unexposed etch resist takes long, doesn't work well and if you leave it too long the developed etch resist will break as well.

I use a laser module attached to a 3D printer to draw the PCB (LCB?) on the etch resist. This laser almost instantly solidifies toner for laserprinters and also almost instantly hardens dry film.

Using powdered toner and a laser would be a much quicker way to apply etch resist since the excess can be wiped off and reused easily. The problem is applying a uniform layer of toner.

Suspending toner on the surface of water and hydrodipping the plate seems to work but drying takes too long.

Spray coating could work but is messy.

Isopropyl alcohol softens the toner too much making it impossible to clean the excess off.

I have not tried using a roller or electrostatic application yet but that could work well.

Does any of you have experience with this and have ideas/advice?