Double-sided PCBs

With overhead expenses

Basic copper Final copper (1)Min. ring (2)Basic copperFinal copper (1)Min. ring (2)


The min. thickness of the final copper is given in the above table.



1. Final copper

2. Min. ring

3. Final diameter of the hole after plating and soldering

4. Drill diameter

5. Pad diameter    


Plated through-hole microsection



The strength of the hole metal cylinder is less in holes with larger diameter. It is not recommended to use plated through holes with the diameter larger than 5 mm for electrical contacting between the layers.  The picture shows a possible solution with using plated through holes with smaller diameter, whose final conductivity is equal to that of the copper cylinder of a large diameter hole, if plated.