Hole plating thickness & via size?


Footprint libraries I use are created mainly for DIY PCB manufacturing, but since I’m going to try Seeedstudio Fusion PCB service, I need few questions answered.

How can I calculate drill size, corrected for hole plating? For Example, if I want finished plated hole with diameter of 38mils, what is the drill size I should use (40mils-42mils)? Is there any standard formula to calculate drill size for Fusion PCB service? Something like: required diameter + 4 mils?

I also need confirmation regarding minimum via size. By searching the forum I found post with following minimum values: 12mils via hole and 24 mil via pad? Is this minimum via size? I also need to know what is the current capacity of minimum via size.

Thanks in advance,

Hi Milan,
1.please ingore the finish hole, design the size of drill hole what you needed, our manufacture will deal it.
2.the minimum via is 12mil and the dia is 25mil.

From the reply given … i understand that the minimum ( outside diameter ) pad size for a via is 0.635 mm ( 25mil ).
The minimum via hole size is 0.3 mm ( 12 mil ).
I also understand that the minimum trace width is 0.15 mm ( 6 mil )
The minimum space between traces is 0.15 mm ( 6 mil )

Is this correct ?

yes,you are right