Electronics Forum | Thu Oct 05 17:05:36 EDT 2000 | JAX
These types of foil kits work just fine as long as they are used before expiration. Scraping off the epoxy coat gets a little tough on fine pitch pads and etches. I have always like to use a solder sample board to retrieve my bits & pieces from whene
Electronics Forum | Wed Nov 13 22:30:05 EST 2002 | davef
Methods for performing repairs: * 7721 - Repair & Modification of Printed Boards & Electronic Assemblies. * On-line guides at Circuit Repair Technology [ http://www.circuittechctr.com ] site. Roughly from East to West, service companies that perfor
Electronics Forum | Thu Feb 14 04:38:43 EST 2008 | marjorie
Anyone knows why BGA fell off sometimes from the board? I was running in a single sided only. I encountered a BGA falling off from the pcb pad. The pcb is ENIG and lead free process. The pads had no solder and didn't looks like having a black pad thr
Electronics Forum | Tue Mar 08 11:50:55 EST 2011 | pgoodyear
As a technician that does frequent board level repair / rework some issues have come to mind. I have been an electronics technician for almost 50 years. In that time I have seen the evolution of electronics from point to point wiring using vacuum
Electronics Forum | Fri Nov 26 06:18:18 EST 1999 | stefano bolleri
Jeff & Ted, we have used a dispensing system too and yes, I agree, we are not too happy with the results. Not at the point that it doesn't work, though. I think our problem basicly is that we have selected an entry-level dipensing system. We are app
Electronics Forum | Wed Oct 10 20:35:17 EDT 2001 | djarvis
Stephen, I don't understand this at all mate. 1. If you don't place a QFP and get bridging across the bare pads, you were gonna get absolutely horrendous bridging if you did put one down. That points to poor printer set up or stencil design or both
Electronics Forum | Thu Jun 24 11:54:36 EDT 2004 | rickw
many solder-ball issues can be resolved by reducing the aperture size, usually 10 to 15% reduction will work. If the aperture size is the same as the pad size paste tends to be squished out under the part, paste off pad under the part will liquify a
Electronics Forum | Fri May 26 04:58:19 EDT 2023 | auriga2001
I agree with the two other replies. Left alone, it is a defect. If it's just excess adhesive or coating, you can use IPC-7711/7721 'Rework, Modification and Repair of Electronic Assemblies' for guidance on removing. Section 2.3.1 explains how to te
Electronics Forum | Wed Nov 19 10:47:37 EST 2014 | grahamcooper22
Probably not all the overpinted paste is flowing onto the joint. You may need a paste with great coalescence properties so it all flows together, and doesn't leave any on the resist. Does the paste drip out the through hole too ? If so it suggests it
Electronics Forum | Wed Sep 19 21:04:57 EDT 2007 | wailiang81
Hi,davef, thanks for your concern. The condition was the pasted printed off with around 0.8~0.9mm from the land pattern. This will easy observe at QFP area. At fiducial, the stencil seens aligned accurately. Once solder bridge happend, its easy to
