Electronics Forum | Thu Aug 30 20:35:51 EDT 2012 | davef
A common bottomside heater configuration is IR-Convection-Convection. One of the big advantages of the IR zone is its ability to allow the flux carrier to spread and dry slowly before the board reaches the convections zones, which can blow wet flux c
Electronics Forum | Tue Nov 14 08:52:07 EST 2017 | davef
If you think the problem is occurring in the box and it is wide spread, consider replacing your solder paste with your paste supplier. There are paste formulations aimed at the solder balling issue that some LF pastes create. On tuning your reflow r
Electronics Forum | Tue Nov 02 17:52:17 EST 1999 | Dave F
Jim: Several points: 1 If you�re correct about corrosion of your component leads (which is entirely possible if the leads are steel, as you say), then the AIM 264-5 no-clean may not be aggressive enough to remove the corrosion you are seeing routin
Electronics Forum | Tue Feb 10 15:13:06 EST 2004 | patthemack
Hey Vinny, Sorry I haven't looked at this for a while. 3 things to try: Tombstoning- The ground plane side is larger because the solder mask allows for a little slop at the board shop (clearance around a pad of a few mils). Since there is not a defi
Electronics Forum | Tue Oct 13 18:28:51 EDT 1998 | Graham Naisbitt
Upinder, Using IPA does not cause the residue, it simply exposes it. Given that all fluxes leave reisdues, it follows that these MUST be benign - but how do you know, and how do you control it. You are using flux to remove oxides and give you a go
Electronics Forum | Thu Aug 26 16:48:37 EDT 2004 | davef
You're correct. Operators shouldn't be doing "touch-up". [No value added] Take that as your clue for areas to improve process. Babbling about touchup: * Left to itself, touchup feeds on itself, operators are parinoid that inspectors will "ding" th
Electronics Forum | Mon Apr 25 16:25:07 EDT 2005 | Mike Konrad
Hi Carl / Bill, I seem to miss your point regarding disclosure. As I CLEARLY stated, it is the perception of damage more than the possibility of damage. As a twenty year veteran of de-fluxing systems, I can assure you that there remains enough con
Electronics Forum | Tue Jul 04 02:31:55 EDT 2006 | Mustang
Calling for an input from the Experts our there. Our customer is questioning the cleanliness of the no-clean product that we produced for them. We were asked to clean the board (localised cleaning) after rework (IC need to be changed due to an up re
Electronics Forum | Wed Dec 24 18:31:04 EST 2008 | hegemon
If they share a common ground plane you are in for some difficulty in trying to prevent the second part from heating too much. What happens to the underfill material when it is softened by being heated beyond the 160C? Does it harden up again, or b
Electronics Forum | Wed May 09 10:40:10 EDT 2001 | davef
First, your primary side component pads should be designed according to SM-782A, "Surface Mount design & Land Pattern Standard". Next if you did that and your secondary side component pads are the same size as your primary side components, your diff