Category Archives: Quality


Dec05
Both solder joint bridging and open solder joint happen at same BGA?

post on December 5, 2018

Is that possible for both solder joint bridging and open solder joint defect occur in the same BGA (Ball Grid Array) or CSP (Chip Scale Package) device? It is rare to observe both solder joint bridging and open solder joint … Continue reading →

Process, Quality, Soldering     WorkingBear    Views (9,871)     comment (0)
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Jun19
Will Increasing Solder Paste Volume Help Prevent MLCC Cracking?

post on June 19, 2017

Figure: Will Increasing Solder Paste Volume Help Prevent MLCC Cracking? Recently, Workingbear received a complaint from R&D asking us to increase the solder paste volume on the MLCC (Multilayer Ceramic Capacitor) component pads to improve a capacitor cracking issue. R&D … Continue reading →

Design, Manufacture, PCB/FPC/PTF, Quality, Reliability, SMT, Soldering     WorkingBear    Views (8,281)     comment (0)
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May03
Trouble Shooting Guide for Plastic Injection

post on May 3, 2016

Trouble Suggested Remedies (Solutions) DIMENSIONAL PROBLEMS Shot-to-shot dimensional variations Increase injection pressure Maintain uniform pad (cushion) Repair leaking back flow value if pad cannot be maintained Increase screw forward time Maintain uniform cycle Eliminate un-melted particles (see below) Use larger … Continue reading →

Plastic, Quality     WorkingBear    Views (5,772)     comment (0)

Jul01
Why do thinner PCBs will need carrier for reflow process?

post on July 1, 2015

As the career of Manufacturing Process Engineering(MPE), WorkingBear has noticed a constant battle between Designers, Marketers, and Manufacturers. Marketers always want  thin, modern design that look thin. Designers think fabrication is simple, while Manufacturers want  strong, robust, sturdy assemblies that … Continue reading →

Design, Glue/adhesive/epoxy/underfill,, PCB/FPC/PTF, Process, Quality, SMT, Soldering     WorkingBear    Views (16,721)     comments (2)
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Jun24
Case study for the mold-in insert screw boss broken

post on June 24, 2015

In a previous discussion, WorkingBear identified potential root causes for screw boss cracking after mold-in screw nut insertion. Following a complaint from the field, we asked EMS and the plastic injection supplier to double-check their inventory and found that approximately … Continue reading →

Design, Plastic, Quality     WorkingBear    Views (15,578)     comment (0)
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