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 | Wed Dec 22 19:09:17 EST 2004 | rohman23
Very strange...I just logged into the internet to come post this very question for all the lurking experts. We have a 16 layer rigid-flex that we have never baked. Our board vendor is expressing concern that we do not perform a pre-bake before assy
Electronics Forum | Wed Dec 22 18:09:07 EST 2004 | kmorris
At a previous job I had been taught that when reflow soldering polyimide flex circuits, it was necessary to pre-bake them before reflow soldering to prevent delamination. Our procedures said that there must be a 1hr bake prior to reflow, and the flex
Electronics Forum | Thu May 29 10:14:51 EDT 2003 | davef
In itself none, but heating moisture laden flex can cause the flex to delaminate.
Electronics Forum | Fri Oct 01 10:05:29 EDT 2010 | rrpowers
You don't necessarily have to bake the flex circuits, but you do have to worry about moisture. Polyimide is very hydroscopic, and depending on the flex construction, any moisture in the product can lead to delamination. Adhesive based flex circuits
Electronics Forum | Wed Apr 28 12:08:02 EDT 2010 | tjg
Our latest designs are flip chip on flex based and we have issues with delamination/blistering. We know it is related to our vapor solvent (n-Propyl Bromide based) attacking an inner layer adhesive. Has anyone else ever heard of something like this?
Electronics Forum | Thu May 29 10:42:40 EDT 2003 | swagner
So is it fair to say that on a moisture laden double sided flex circuit you could see an increase in tombstoning on the 2nd pass due to warpage created by delamination? In other words a 0603 for instance could tombstone due to the delaminated surfac
Electronics Forum | Fri May 02 12:41:16 EDT 2003 | Chris Lampron
Hi Chris, I had worked for a flex circuit house for 10 years. You should be able to follow your solder paste guidelines for times and temps. You may want to consider pre-baking the flex if it is made with Kapton. Kapton is Hygroscopic and will delam
Electronics Forum | Wed Apr 04 14:29:16 EDT 2007 | rgduval
Anyone have experience wave soldering rigid flex assemblies? I've just picked up a new job from a customer; it's a rebuild for the company, but new to me. The customer had previously taken their business elsewhere due to delamination problems with
Electronics Forum | Thu Feb 14 20:24:07 EST 2002 | scott
My first reaction would be to run! FAST! Flex -- well, it... flexes... and isn't flat. While you assemble it, While you transport it, While it goes through the oven... SMT Connectors typically need to be held down during reflow. Fiducial types are
winsouce.jpg)
.gif)
