Electronics Assembly Knowledge, Vision & Wisdom HOME PROGRAMS DIRECTORY SUBSCRIBE ARCHIVE/TRANSLATE Ask the Experts << Page 1 of 34 >> Arranged via association with Circuitnet.. See the Expert Panel | Submit A Questions | Join the Panel Programs are sorted by published date, most recent first. Directory Search         Program Search         What Causes Black Pad? What is the primary cause of Black Pad and/or pad contamination during the assembly process? Ask the Experts Solder Paste Past Shelf Life We have some solder paste that has been in a sealed box at 4 degree Celsius for more than 8 months. The shelf life is 6 months. Can it be used? Ask the Experts Solder Paste Life on the Stencil Our solder paste has a specified life on the stencil of 10 hours. After 10 hours of manufacturing, do we need to remove all the paste and scrap it? Ask the Experts A Generic Reflow Profile We have a wide mix of PCB assembly types. Some propose we use the same reflow profile regardless of the PCB thickness, thermal mass or component mix. Ask the Experts Selective Printing for BGA Components We use common BGA packages on many of our low-end products. To save cost, could we print paste only on the pads that have functional requirements? Ask the Experts Solder Paste Alloy Check We accidentally assembled boards using lead-free paste. Is there an easy method to check which paste has been used? Ask the Experts Un-cleaned PCB Assemblies Potted Our PCBs were soldered with a washable flux. The flux was not removed and the boards were potted with epoxy based resin. What can we expect? Ask the Experts What Causes Component Rotation During Reflow? We are using a large 2 pin SMT inductor. During reflow soldering it rotates almost 30 degree. Why is this component rotating during reflow? Ask the Experts Toe Fillet Requirements on Gull Wing Components Is a toe fillet required on gull wing components? We have some gull wing components that have no toe fillet, but all other requirements are met. Ask the Experts Zip-lock Bags vs. Heat Sealed Bags Are zip-lock bags vs. heat sealed bags an acceptable option for storage of moisture sensitive components? Ask the Experts Ask the Experts << Page 1 of 34 >> About | Advertising | Archives | Contact | Directory | Directory Search | Directory Submit | Privacy | Programs | Program Search | Sponsorship | Subscribe | Terms | Translate Circuit Insight 6 Liberty Square #2040, Boston MA 02109 USA Jeff Ferry, Publisher | Ken Cavallaro, Editor/Business Manager Copyright © Circuitnet Media LLC. All rights reserved. A Circuitnet Media Publication