Electronics Forum | Thu Jun 04 12:22:12 EDT 1998 | John Allan
| | | Hello: | | | BACKGROUD: SMT components soldered on the top-side of boards that also require wave soldering have the potential to reflow during wave soldering. Reflowing these components during wave soldering is not good. It can cause cold jo
Electronics Forum | Thu Jun 11 23:35:40 EDT 1998 | Scott McKee
| Does anybody know if a contraption exists that will minimize a PCB's tendency to become slightly bent after reflow? We have a new product that we're planning to assemble in a couple of months. The board is 9.7" by 13.4" and it is imperitive that
Electronics Forum | Fri Mar 27 02:05:26 EST 1998 | Jon Gruett
AS the previous have stated there are several ways to get the BGA's off the board. Let me first ask you a couple of ?'s. 1)Are you concerned at all with the damage to the baord or the BGA? 2)Are you eventually going to need to consider the reattac
Electronics Forum | Tue Aug 07 08:20:47 EDT 2001 | CPI
Are there other components on the board? If so, how does solder quality look on them? Are they all reflowing? Are the sections of the uBGA�s sitting on a ground plane? Sounds like un-even heating. You should attach a couple thermal couples and see h
Electronics Forum | Sat Oct 19 08:14:27 EDT 2002 | johnw
The world of the CM isn't alway's a happy one and the problem is that some one else is alway's paying your wages, that soemone else beign the customer so you really have to do what they say. The board profilign one is a constant one round our place a
Electronics Forum | Tue Jan 28 16:27:43 EST 2003 | MikeF
I agree with most of the other suggestions here, but 90 C for a topside preheat temp seems low to me. I remember aiming for 98 to 104 C for topside temp just before hitting the solder. Boards that had large ground/power planes or a lot of layers I wo
Electronics Forum | Fri Aug 01 13:30:14 EDT 2003 | SuePH
I understand your need for more wave solder imput. It seems to me that every year the pwb's that I am given for solder wave are thicker and have more ground planes. There have been times I have asked questions on SMTnet about pwb's received in hous
Electronics Forum | Mon Oct 13 17:50:30 EDT 2003 | davef
IPC-7530 "Guidelines for Temperature Profiling for Mass Soldering Processes (Reflow & Wave)" As you observe, the temperature you measure will depend on what you are measuring. For instance: * Hottest temperature in the oven - air in the oven * Hott
Electronics Forum | Mon Jan 26 03:45:37 EST 2004 | Vinny
Hi All, We are producing a veriety of RF related PCBAs in which we see Unsolder/Mislaigned on a regular basis. In these baords usually one of the pad is connected to a signal trace and the other pad is connected to very huge ground plane. This gro
Electronics Forum | Mon Mar 08 09:03:17 EST 2004 | russ
Is this problem really related to the size of the BGA OR the size/thickness of the PCB? Would I be correct in assuming that your pre-heater is small in size? Usually a board warps like this when the ramp is to great at the localized area. the imme
