I have long been a happy user of Positiv 20, consistently getting superb results.
My stockist is now carrying the Cramolin product which appears to have very different properties.
I have very small areas on the developed board where the resist doesn't seem to have been exposed at all, leaving little copper dots all over the place which is extremely ugly and has the potential of causing electrical problems.
Does anyone have experience with Cramolin?
My setup is the same as the Positiv 20 technique:-
350nM UV tubes about 150mm away from the board. Two tubes are used, with the pcb artwork held down onto the panel with a piece of glass. I know glass absorbs a fair amount of the UV, so my exposure with Positiv 20 was around 10 minutes.
I have exposed for up to 15 minutes using Cromalin, but am stillgetting the same poor result.
I have been in the habit of drying my Positiv 20 boards in a warming drawer. Could the temperature have anything to do with it?
I am very frustrated over all this, especially over the number of bad boards when the chemicals cost so much in this country!
My stockist is now carrying the Cramolin product which appears to have very different properties.
I have very small areas on the developed board where the resist doesn't seem to have been exposed at all, leaving little copper dots all over the place which is extremely ugly and has the potential of causing electrical problems.
Does anyone have experience with Cramolin?
My setup is the same as the Positiv 20 technique:-
350nM UV tubes about 150mm away from the board. Two tubes are used, with the pcb artwork held down onto the panel with a piece of glass. I know glass absorbs a fair amount of the UV, so my exposure with Positiv 20 was around 10 minutes.
I have exposed for up to 15 minutes using Cromalin, but am stillgetting the same poor result.
I have been in the habit of drying my Positiv 20 boards in a warming drawer. Could the temperature have anything to do with it?
I am very frustrated over all this, especially over the number of bad boards when the chemicals cost so much in this country!