Electronic – whatis the difference between mounting holes and through holes


I am new to pcb design, and I am using eagle for this purpose. I am confused by mounting holes and through holes. They are all holes, what's the difference?

In eagle, layer of drills(layer 44) is used for through holes, holes layer(layer 45) is used for mounting holes. am I right?

Best Answer

When eagle generates Gerbers, holes end up as non-plated holes. For a mounting hole, it's good when it's not plated.

Making non-plated holes requires an additional step in the fabrication process. Some PCB fabs do non-plated holes as a part of their standard service. Some automatically convert non-plated holes into plated holes. Some charge extra for non-plated holes.

screenshot of layout in Eagle

photo of a fabricated PCB with non-plated hole