I am trying to expose the solder paste only over the copper zones but when selected the same area where the zones were defines and try to make a non-copper zone in F. paste, it is poured over all other components and does not keep clearance in any of them resulting in what is in the attached picture. Is there a way to only exposed same copper areas keeping clearance on other footprints?
I really appreciate any help here.
First: Sort out your layers. Paste is the mucky stuff that sticks to your fingers. You probably want to create cutouts in the solder mask layer (which is the (usually green) paint on the PCB.
You can do this by right clicking on the zone and then Create from Selection / Create Polygon from Selection, and make sure you do not delete the Source Objects. I am not exactly sure what you want to do with the clearance. You can experiment with “Create Bounding Hull” with a negative gap. I just tried it and it seems to work, but the created polygon is not filled initially. But you can set the Filled property of the polygon in the next step.
Edit: Duh, the question is about solder paste. My glasses must be illuminating the wrong part of my brain.
I’m not trying to tell you your business, but I suspect that most assembly houses aren’t going to be happy with that enormous expanse of solder paste. Generally, large areas are broken up into smaller rectangles, to reduce voiding and floating.
Yes, that is not going to work. Solder paste is usually spread with a squeegee, and with those big open gaps, the squeegee is going to dip into the hole so there is no solder paste left.
And there is no mechanism in KiCad to calculate clearances apart from the copper zones. For all other zones you have to manually draw it the way you want it to be.
Thanks for the answers. I made it exposing the bare copper layer and it work as I was expecting. I was trying to keep the silver color for all these zones but copper exposed is fine.
After producing the board with exposed copper, the exposed part will still have the silver color of the HASL, or gold if you go for ENIG finishing.
By default, there is no way to get exposed copper with noting on it. And you probably don’t want it any way as it would corrode.
So during the manufacturing,
They etch the copper.
They add solder mask (the green layer) where it should be.
Then they cover the renaming exposed copper with the finishing HASL or ENIG, so it end up silver or copper.
Then on top of that they can add Solder paste on the pad that will receive SMD components. This is also silver color, but this is not flat. And they won’t do big surface of it.
