Electronics Forum | Fri Jun 18 06:54:43 EDT 1999 | Paul McMichael
A user of one of our components exceeded the floor life of some plastic BGA components. They did do a pre-bake prior to SMT reflow but only 72 hrs at 40C and not the recommended 12 hours at 125C. I've recommended accoustic microscopy to look for popc
Electronics Forum | Fri Jun 18 13:30:01 EDT 1999 | John Thorup
| A user of one of our components exceeded the floor life of some plastic BGA components. They did do a pre-bake prior to SMT reflow but only 72 hrs at 40C and not the recommended 12 hours at 125C. I've recommended accoustic microscopy to look for po
Electronics Forum | Sat Jun 13 11:00:21 EDT 1998 | Earl Moon
| We are very concerned about outgassing in wavesoldering. | If anyone knows how to use properly well pcb's before soldering in order to avoid this problem please let me know. I have this problem in FR4 large double sided pcb's. My soldering line is
Electronics Forum | Thu Nov 16 11:45:15 EST 2006 | markb
I still think the best bet is probably an SMT pre-bake operation to ensure that there is no moisture in the board. Vapor pressure is usually the leading cause for delamination, so removing the source should significantly help out. Unfortuantely, pr
Electronics Forum | Fri Jul 13 08:54:18 EDT 2007 | rgduval
Has your board house reviewed the PCB layer stack? Make sure that the layers are balanced in copper weight, etc? Have you tried pre-baking the boards? We just had an issue with some boards warping that have never warped before for us. It happened
Electronics Forum | Thu Dec 09 12:07:15 EST 1999 | Chris May
Charmaine, Have a look at the discussions that took place on the 5/11/99 (5th November)and I think you will find a veritable font of knowledge. I know I did. You will obviously have to select the required listing from the options at the bottom of th
Electronics Forum | Wed Jan 05 17:53:52 EST 2005 | SuePH
We had a contract in house that included a flex board which required an 18 hour bake at 105 degrees. The other brds got along fine with 2 hours, but the flex board would delaminate until we went to this long bake. I don't know how the engineer came
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 | Tue Oct 24 09:35:33 EDT 2006 | jax
The need to Pre-Bake depends on multiple variables: 1. Packaging from the vendor (dry packs, vacuum sealed, etc...) 2. Storage at your facility (temp, humidity, etc...) 3. Moisture absortion rate of Laminate (FR406BC is one of the highest) Other rea
Electronics Forum | Wed Feb 20 12:22:14 EST 2008 | tonyamenson
iv40, I don't suppose you know/remember what base material you were using that caused the problem and what material you switched to was, do you? We just pre-bake all our lead free PCBs as a precuation but I would like to remove the process if I can
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