Hello to  all of you,


Currently,we  are designing a double sided reflow board.
All our  assembled boards  have to pass electrical test, preferably on a bed of nails.
Is it  good practice to close all  through hole testvias by paste screening in order to create good 
vacuum conditions when testing ?
So, I want to include these vias in the paste screen artwork.  What is a good diameter in the paste
screen for closing vias with a finished hole diameter of 8 mil ?
Is there not a risk that the solder paste will flow through the via holes and causing shorts at the other side
during the second step of reflowing ? The board has a thickness of 95 mil.
Anyone has some experience in this matter ?

Thanks in advance.

Cor Coolen

Board Designer


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