Electronics Forum | Thu Dec 13 20:54:23 EST 2001 | davef
There is neither �nominal thickness� nor �is there a set maximum� for via masking. We use some of our vias as test pads. So, as you�d expect, we get rabid when we get mask bleed onto these pads. IPC-6012 - Qualification & Performance For Rigid Pri
Electronics Forum | Thu Dec 13 15:14:07 EST 2001 | cc
Does anybody know what is the nominal thickness for via masking and is there a set max.? I recently have some bridging on some fine pitch components and my suspicion is that the new fab with new via masking is the culprit. Thanks CC
Electronics Forum | Mon Jan 23 22:53:31 EST 2012 | davef
= 0.66 aperture opening to the stencil wall has been shown to provide the best transfer efficiency and repeatability of the deposited paste. Values from 0.66 to 0.8 insure a good paste release from the stencil. The biggest impact on area ratio is the
Electronics Forum | Sat Oct 12 05:40:05 EDT 2002 | Kenture
Hello All, I am having issued with insufficient solder due to via in pad. It is a 10 mils via and PCB is 70 mil thick. Six mils stencils was used since there are some 20 mils (No clean process). Any recommendation? Thank you.
Electronics Forum | Fri Oct 18 22:32:20 EDT 2002 | mdm4ua
If you have room try putting a small piece of tape on the bottom of the stencil right next the aperture that is giving you the problem. The added height of the tape (Kapton tape is usually about 3 mils thick) will likely give you a heavy enough depo
Electronics Forum | Mon Feb 26 20:02:42 EST 2001 | davef
First, I don�t understand why your board fabricator can�t do a good job plugging your vias. Additionally, when you consider that they forgot to plug the first batch of boards, it makes me wonder if they are desirable as a supplier. Generally, we us
Electronics Forum | Wed Jul 23 08:18:29 EDT 2008 | davef
Q1. Is this a standard process for plugging? A1. Not as such. We checked both IPC-6012 and IPC-SM-840. Neither comments on plugging. So, your fabrication notes rule the day. Q2. Is this okay for such thick PCB's or is it mandatory to use a special pl
Electronics Forum | Wed Jul 23 03:04:57 EDT 2008 | gfro
Hello, We are using a PCB with thickness 3.2mm 4 layer and lot of through hole via's of diameter 0.4mm. We specified our PCB vendor to do plugging. Now we have big problems, that after 1..4 weeks we measure a low resistance between track's/via's of
Electronics Forum | Fri Jan 06 11:29:28 EST 2006 | mdemos1
Hi. I was curious what some common accept/reject criteria would be on copper wall thickness. For instance, if 1 ounce copper is used, I believe the IPC specification is 0.001" minimum thickness. Should the order be rejected if there is one measure
Electronics Forum | Sun Nov 24 20:43:15 EST 2019 | sssamw
If you want to check if solder mask on tented via, better to do cross section to have a clear view. Sometime supplier will not tell you the truth once you ask question for potential quality issue.
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