Electronics Forum | Tue Feb 01 21:53:06 EST 2000 | Dave F
Emmanuel: You have choices to prevent the solder paste from flowing to the second side during reflow: 1 Have your board fabricator plug the vias. 2 Put a temporary solder mask on the secondary side vias. 3 Have your designer relay-out the vias unde
Electronics Forum | Mon Mar 04 11:08:56 EST 2002 | Matt Kehoe
We have a customer that desires to have their via holes plugged with solder after assembly. Is it possible to add the via holes to the stencil and print paste into them and expect them to plug? If so, how much paste? One to one on the stencil opening
Electronics Forum | Mon Nov 05 07:22:02 EST 2007 | aj
Hi, We have had this before - yes they can be plugged and metalised on top . aj...
Electronics Forum | Tue Mar 05 22:34:27 EST 2002 | YoYo
You better be careful how you plug vias at screenprint - we currently have a customer that wants vias plugged, so we had a 2% aperature reduction so we would not have to much paste, I believe it should have been reduced more because some of the solde
Electronics Forum | Mon Nov 05 06:27:23 EST 2007 | grantp
Hi, We are also interested in this, and I have heard you can get the PCB's with the via's plugged. Also, if the via's are small, the solder should not penetrate? Anyone have any further info? Grant
Electronics Forum | Thu Jan 06 16:11:07 EST 2005 | Chunks
It appears your board house is having a problem with the solder resist (mask). From the couple pix it appear that the holes are being plugged by the mask, so your HASL is not able to be blown out during the hot knife process. Time to call your boar
Electronics Forum | Wed Nov 21 15:02:46 EST 2007 | jlawson
From info I have been told from design standpoint, via in pads helps with managing EMC issues with working design, in particular for high speed digital/dense populated type PCB's. We had a manufacturing customer that had very low yield because of th
Electronics Forum | Mon Mar 04 17:52:59 EST 2002 | davef
Yes, providing the surface of the via is solderable. * If so, how much paste? => Vias come in various sizes. Boards vary in thickness. So, the amount of paste to fill a via varies. Roughly, you�ll need twice as much paste as the volume of the via
Electronics Forum | Fri Nov 23 16:32:05 EST 2007 | davef
There a several things you can do to prevent the solder wicking down the hole with the current design, and that's where you should focus. Cost goes up as you go down the list, but in neither case do you need to respin the board, have solder starvatio
Electronics Forum | Tue Sep 25 14:08:59 EDT 2001 | davef
Oooo, the solder on the pad and PGA ball is flowing during reflow down the via to the secondary side? Why didn�t you say so?? ;-) Why would you expect that gravity and capillary action wouldn�t force solder to flow down the solder plated via to the
