Electronics Forum | Thu Jul 15 16:29:54 EDT 2010 | dilogic
I am trying to locate procedure for PWC calibration/adjustment on GSM1/2 machines (after moving feeder plate), but can't find it in the manuals. I would appreciate if somebody can give me a hint... - Deni
Electronics Forum | Fri Jul 16 11:27:57 EDT 2010 | davef
Consider: * Bow & Twist IPC-TM-650; Method 2.4.22 * Previous threads on SMTnet, like: http://www.smtnet.com/Forums/Index.cfm?CFApp=1&Message_ID=54498
Electronics Forum | Tue Jul 20 16:02:12 EDT 2010 | mikesewell
You may want to look at IPC 7721 Method 3.2 Bow and Twist Repair. In extreme cases you may need clamp or weight the pcb with bow in the other direction to yield a "flat" pcb in the unrestrained state. You will have to take the PCB up to or slightly
Electronics Forum | Wed Jul 21 11:12:05 EDT 2010 | remullis
I have some 13" long boards that warp considerably during first pass through reflow (no center support), what I've done to improve this type of warpage is stiffeners along the front and back edge. This may help with twisted boards as well.
Electronics Forum | Wed Jul 28 08:41:47 EDT 2010 | vetteboy86
I believe we are seeing some wetting issues as we have tried to bake these assemblies ourselves. Our PCB supplier is coming in next week to address the issue. Is there a rule of thumb or formula for determining correct parameters. Thanks
Electronics Forum | Sat Jul 17 12:42:24 EDT 2010 | oakie70
How do you merge two databases in UCT 52? Or for that matter, does anyone have a book out there for UCT 52?
Electronics Forum | Fri Jul 23 02:17:26 EDT 2010 | joseph_smile
by viewing your posting i came to know this is solder ability issue which is because of marginable solder ability of PCB / components, just ensure that issue due to PCB or component . check the msl of of substrate / component. verify the baking r
Electronics Forum | Wed Jul 28 09:15:46 EDT 2010 | vetteboy86
I took a pad that did not have any solder flow (wetting issue with pad) and not reworkable with soldering iron, and scraped with an exacto knife. After scraping the pad soldered fine. Any suggestions?
Electronics Forum | Tue Aug 03 17:13:41 EDT 2010 | bradlanger
Craig, If it is LF Hasl it sounds like it applied too thin exposing the intermetallic layer wich is not solderable. We call out a minimum thickness of 80 microinches and have good results. We have had shops in the past that did not control the Hasl
Electronics Forum | Mon Aug 09 12:36:19 EDT 2010 | cobar
IPC TM 650- Solderability of Metallic Surfaces http://www.shanelo.co.za/List%20of%20articles/IPC%202.4.14%20Solderability%20of%20Metalic%20Surfaces.pdf
