Electronics Forum | Thu Jul 05 21:42:28 EDT 2001 | davef
Most of our boards are fabricated with solder mask over bare copper [SMOBC], but we have couple where the solder isn't removed before masking. And ever so offin they's a liddy bit mo' solder than we'd like, which when reflowed, ends-up connecting so
Electronics Forum | Tue Oct 19 19:25:40 EDT 1999 | Jeff Sanchez
Carol, I think the guys are right about you stand off problem but I want to address the wrinkleing of your masking. Although I think the temps you are subjecting the board to are very high and more than likely creating problems of their own. I th
Electronics Forum | Tue Feb 09 16:53:06 EST 2021 | SMTA-64387083
The size of the pad changes among the two. A solder mask defined pad will always be larger than a copper defined by your mask expansion setting. This will affect paste volume, if your standard paste aperture is designed for copper defined pads you m
Electronics Forum | Wed Aug 09 16:30:43 EDT 2000 | MarkS
Has anyone had (successful) experience placing testpoint vias under BGAs? We already have conventional vias, but we're contemplating converting them into testpoints (probably by enlarging the bottom-side copper diameter to .036" and opening the bott
Electronics Forum | Mon Jul 18 12:24:53 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Mon Jul 18 12:25:30 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Fri Feb 17 19:23:05 EST 2023 | SMTA-64387083
Read the articles everyone else recommend. I haven't read of them but I will say this. A Solder Mask Defined pad is a copper flood that has much more thermal mass than a Non-Solder Mask Defined pad so it will heat and cool at a slower rate. I suspect
Electronics Forum | Wed Jun 30 10:37:11 EDT 1999 | Boca
We are wave soldering some fabs with a lot of unmasked trace area along the edges. The trace area is solid copper covered with tin / lead, no masking, no components along the edges, same on solder side and component side (goofy board design). Inste
Electronics Forum | Wed Jun 30 12:14:40 EDT 1999 | John Thorup
| | We are wave soldering some fabs with a lot of unmasked trace area along the edges. The trace area is solid copper covered with tin / lead, no masking, no components along the edges, same on solder side and component side (goofy board design). I
Electronics Forum | Wed Jun 30 11:38:05 EDT 1999 | Brian Conner
| We are wave soldering some fabs with a lot of unmasked trace area along the edges. The trace area is solid copper covered with tin / lead, no masking, no components along the edges, same on solder side and component side (goofy board design). Ins
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