Electronics Forum | Sun Oct 10 17:57:48 EDT 1999 | JohnW
Folk's, I'm just tying up some loose end's on my Master's Thesis on solderballing @ wave soldering and the effect the topography of the mask / PCB has on it. I was wanting to do a straw poll on you guy's as to the type of resist's you are using Glos
Electronics Forum | Mon Oct 11 13:08:29 EDT 1999 | Dave F
| Folk's, | | I'm just tying up some loose end's on my Master's Thesis on solderballing @ wave soldering and the effect the topography of the mask / PCB has on it. | I was wanting to do a straw poll on you guy's as to the type of resist's you are us
Electronics Forum | Wed Jun 30 17:58:01 EDT 1999 | Boca
| My guess would be trapped flux continuing to be active after soldering. Is the tarnish there immediately after exiting the machine? Do you remove the mask and wash right away? If the solder is reflowing under the mask on the component side it wo
Electronics Forum | Tue Feb 29 21:53:46 EST 2000 | Kelvin Chow
Dear Robert, On PBGA assembly, BGA sphere shrinkage number depends to the following factors, a. BGA Sphere size (before reflow) b. Solder mask opening diameter As far as I know, no formular has been established yet. Most of my friends just collect
Electronics Forum | Tue Feb 29 21:53:46 EST 2000 | Kelvin Chow
Dear Robert, On PBGA assembly, BGA sphere shrinkage number depends to the following factors, a. BGA Sphere size (before reflow) b. Solder mask opening diameter As far as I know, no formular has been established yet. Most of my friends just collect
Electronics Forum | Wed Feb 28 07:40:26 EST 2007 | realchunks
Hi Roderick, Guess it depends on how you define "minor". If it is just a visual blemish in the mask, there will be no affect o the BGA. If it is through the resist there may be a chance of solder shorting, which will affect it, I doubt it but poss
Electronics Forum | Thu Nov 13 09:27:21 EST 2008 | cisridn
I have tried covering the vias with thermal tape and that did not work. I like the idea of plugging the via with a temporary solder mask. I will try that the next time I build a fixture which should be tomorrow. This is mainly a problem only becau
Electronics Forum | Thu Oct 14 08:01:48 EDT 1999 | JohnW
Gee Dave That's the first time I've ever seen myself listed for a quote! Brian, what your saying is on the whole right, on the surface of it the mask, as long as it's cured properlay shouldn't make a difference but I have to say that I've found so f
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 | Tue Feb 27 22:40:28 EST 2007 | davef
IPC-A-600G, 2.9 Solder Resist [Solder Mask] [snip]"Solder resists are used to limit and control the application of solder to selected areas of the printed circuit board during assembly soldering operations and are sometimes used to reduce dendritic f