Dear Electronics Assembly Colleague:
Summer in Chicago has been great. Several weekends ago blackberries became my favorite "you pick" fruit (surpassing raspberries). The berries are chest high and ripen in sequence on the vine so there is always some new fruit to pick
The BEST BGA Tech Symposium was very energizing with great speakers, great interactions and good eats! My video review is here and my notes are below.
SMTAI Oct 16/17th (paper on QFN reliability post rework) SMTA Webtorial Nov 20th and 27th (a 2-part series on the basics of BGA rework)
Wishing a great rest of the summer!
President, BEST Inc.
We were privileged to have great subject matter experts, very attentive regional process engineers (40+) and the supporting staff at BEST in attendance at this years' tech symposium.
Chrys Shea's presentation ("Better Yields of BGAs through SPI") had some very practical takeaways to go along with her wit, enthusiasm and experience. The highlight for me was that electronic assemblers should make sure that they check their stencils at incoming inspection. She suggested doing a few simple print tests and checking the solder paste volume with SPI to see if volume percentages are within range. Better to do it here than at rework (which is near and dear to my heart).
Mike Bixenman, the "Cleaningologist" ("Cleaning Underneath BGAs") had some very practical suggestions on getting underneath low standoff parts. He suggested going to non-solder mask defined pads underneath BGAs. Increasing the standoff height underneath LGAs by "bumping". Mike also explained clearly what it takes to clean underneath parts-it's a combination of creating the "channel" for cleaning. Having enough energy in the cleaning system to break the "dam" underneath parts and making sure the parts were exposed for the proper time to the cleaning agent. Don Naugler from VJElektronix ( "XRAY Inspection of BGAs") walked the participants through basic X-RAY principals building up to"3D X-RAY" systems and what they can and cannot do. He recommended that engineers consider CT X-Ray for diagnosing and troubleshooting soldering and assembly problems.
Mario Salzo, a black belt from Indium ("Pad Cratering and Graping") went into graping and head in pillow phenomenon. The greatest eye opener here was Mario showing some videos which demonstrated visually how oxidation prevents solder alloys from coalescing and thereby causing HIP defects. The other telling video on putting an oxidized SAC solder ball into molten Sn63 was a real eye opener. It was an AHAAHH! moment.
The cleanup act, saving one of the best for last, ("DFM and BGAs") was Dale Lee of Plexus. One of the most telling comments that came from Dale was the "the pitch of modern devices is now on the order of magnitude of the weave of the PCB laminate"-Wow!. Dale talked about making sure stencils matched the artwork, how to do the routing of BGAs from the IO, how to get around th via dilemma and many more morsels for your design team.
|Last Minute Classes-Availability|
|Below is a listing of classes scheduled in the next 4-5 weeks with openings:
Minneapolis10/4-10/5 JSTD CIT RecertChicago 9/10-9/14 7711/21 CIT Cert 9/19-9/21 610 CIS Cert 9/18-9/19 610 CIT Recert 9/20-9/21 JSTD CIT Recert
Call Bob Wettermann at (847) 797-9250 for further details.
|FAST TURN Component Printing Stencils|
|BEST now produces component printing stencils for a variety of different rework machines (SRT, OKI,PACE, etc). With our vast experience in contract PCB rework as well as our hands-on experience in component rework printing and stencil design we are your new source for component printing stencils. Unlike many machine vendors we do it all in house for faster turns in 2-3 days. Call Chris Edwards at (847) 797-9250.|
"(kon-ser-TEE-nuh)" which is a verb.
The vocabulary you use tells others your level of intellect.
To fold, crush together or collapse in a manner of a concertina (similar to an accordion)
"The car concertinaed when it hit the truck."
|NGold Plating Repair Kit for PCBs|
|If you need to repair gold fingers or other gold plated areas of your PCB check out the BEST gold replating kit.|
|Flux Dip Plates-FAST TURN Avail from BEST|
|BEST now manufactures flux and dipping paste dip plates. Whether you have an OKI, PACE, SRT or Airvac machine we can be your faster turn dip plate supplier turning these custom-machined pieces in 2-3 days.
Call Chris Edwards at (847) 797-9250 for further details.