Electronics Forum | Mon Feb 15 14:30:00 EST 1999 | Dave Turner
| Any info on the pros and cons of FR4 or Polyamide ref the use of soldering PGAs would be helpful. ie. temp co-efficient diffs, baking, wave soldering, Convection reflow etc
Electronics Forum | Wed May 03 16:37:10 EDT 2017 | charliedci
I don't believe there should be any issues with the HASL finish. The issue is how long on the shelf and is a bake out required to remove moisture from PCB, as in any FR4 PCB's that may have had time to absorb moisture.
Electronics Forum | Fri May 15 18:13:35 EDT 1998 | Earl Moon
| | | Does the temp. profiles used to reflow double sided pcb's through a IR oven | | on FR4 board material have to be re-established if it is changed to | | polyimide? Boards will be baked out prior to assembly. | | any response would be most appr
Electronics Forum | Thu Aug 24 15:54:13 EDT 2006 | davef
It depends. What is: * Storage environment and period * Board laminate, epoxy, and copper thickness of PTH * Down stream process * Etc FR4 0.062" thick boards absorb between 0.08 to 0.1%Wt of moisture within a 24 hour period, and 0.2 to 0.23%Wt in
Electronics Forum | Mon Nov 27 17:39:37 EST 2000 | Dave F
Daniel: In response to your questions: * Moisture level (wt%) that may cause delamination in PCB�s. - Certainly, it depends, but 100% moisture will not cause delamination of a PCB. [Now, heating that water is another question, isn�t it? ;-)] *
Electronics Forum | Fri Oct 01 08:15:02 EDT 2010 | rgduval
Is the stiffener a piece of FR4, or a component that needs to be installed? We've done a number of flex assemblies taht have a rigid stiffener, generally a piece of rigid flex, or FR4 that has the components mounted on it. This type of stiffener
Electronics Forum | Mon May 15 12:36:12 EDT 2017 | edhare
I don't believe there should be any issues with > the HASL finish. The issue is how long on the > shelf and is a bake out required to remove > moisture from PCB, as in any FR4 PCB's that may > have had time to absorb moisture. > I don't believe
Electronics Forum | Fri Mar 06 12:54:37 EST 1998 | Earl Moon
| We have been told that we should bakeout FR4 boards prior to assesmbly - i gather from your discussion that you disagree - any details will be sincerely appreciated. Regards. Please bake. I agree. Let me know how we have a disagreement.
Electronics Forum | Wed Dec 19 01:17:13 EST 2001 | ianchan
Hi Experts, I need help here, advice appreciated from all... Production is running a Lot of flex-circuit PCB, through the SMT line, with 0402 components. The flex-PCB is taped to FR4 support "pallets" when processing thru' the SMT P&P m/c. We use
Electronics Forum | Fri Feb 28 01:10:32 EST 2003 | MA/NY DDave
Hi I don't know what FR4 you are using, so check it out to make sure 125 isn't too high. I have seen this done occassionally when the PCBs have bad moisture or other problemx where baking helps prior to assembly and solder, yet I haven't seen it do
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