Electronics Forum | Thu Aug 05 18:21:16 EDT 2004 | davef
Well, it could be the beautiful Jill Masterson, as Goldfinger's trusted card advisor Shirley Eaton, who gave new meaning to the phrase "golden girl." Or more mundanely, gold thickness usually ends-up: * Gold fingers (10 to 100 micro-inches) * Selec
Electronics Forum | Thu Sep 20 07:18:42 EDT 2018 | proceng1
Has anyone else been experiencing this lately? We have had a rash of boards that come in properly vacuum sealed. We store them in the hot room until we are ready to build, and we get bubbles under the solder mask. We've had 4 different jobs, all di
Electronics Forum | Fri Jan 07 07:36:14 EST 2005 | dansmall
I have a Polyimide board that is showing signs of de-lamination. I was wondering what pre-bake times and temperatures other people would recomend for new boards as well for boards that have been on the shelf for 8 months.
Electronics Forum | Sat Jan 08 08:50:35 EST 2005 | davef
Normally, you should not have to bake boards that are properly packaged and stored. Since you are seeing problems, baking makes sense. Consider 125C for 4 to 6 hours. Additionally, look here for more, while waiting for others: http://www.smtnet.
Electronics Forum | Wed Jan 12 10:05:20 EST 2005 | Dreamsniper
we are using polyimide boards 6 inches x 7 inches, 2.5mm thick, 12 to 14 layers, for aerospace industries. I am using a long bake of 12 hours at 70'C prior to manufacturing or exposure to elevated reflow and wave soldering temperature. If schedule i
Electronics Forum | Thu May 29 08:17:22 EDT 2014 | emeto
Edri, if the profile is good for this part and everything else on the board looks fine, I would focus all my attention to the part. How is it packaged? How is it handled? Moisture sensitive - prebake if needed.If nothing helps, try another batch or
Electronics Forum | Wed Apr 23 17:28:46 EDT 2008 | davef
The need to prebake boards to remove moisture from the board [to prevent voiding] prior to wave soldering is driven by the thickness of through hole plating. * 1 thou [25um] or greater requires no prebaking * LT 1 thou [25um] requires prebaking
Electronics Forum | Thu Dec 09 08:29:19 EST 1999 | Charmaine Bode
Excuse my ignorance. Please advise whether it is advisable to pre-bake boards before assembly. Thanks Charmaine
Electronics Forum | Tue Jun 13 22:42:36 EDT 2000 | Dave F
Jeff: Last place I can recall seeing something like that is NASA-STD-8739.3 Requirements like this are not currently in vogue. A modern solder process should conform to J-STD-001, which makes no mention of prebaking boards.
Electronics Forum | Mon May 20 16:56:24 EDT 2002 | Gary
Excess slump of paste and mis-registration can cause solder balls along with moisture. Use same date code of pcb and run with no components, paste only. Also pre-bake boards with humidity sensor in oven. If high humidity, moisture and solvent residue
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