Electronics Forum | Wed Apr 19 20:33:14 EDT 2006 | davef
I just flew in from (insert city) and boy are my arms tired. pr: Likely, you're correct. The "pound-inch" units should have been the give-away, for us. Good catch. If this is the case, the frame fabricator would be the best source for tensioning
Electronics Forum | Mon Aug 27 12:51:32 EDT 2012 | cobham1
I have run 0.031 boards. One of the things you may want to look at is the speed of the oven. With 14 zones you may be going to slow with the board which could be the reason your boards are starting to bow. You might also think about adding stiffners
Electronics Forum | Mon Jun 14 14:30:42 EDT 1999 | Deon Nungaray
| | | | | Hello all! | | | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We d
Electronics Forum | Wed Aug 19 05:00:56 EDT 1998 | Tom Blum
Hi there, I'm actually facing a lot of trouble with PCB's presenting up to 3mm of bow /twist at reception i.e. before assembly. The PCB size is 220 by 230mm. The boards are to be assembeled SMD double sides with 05.mm pitch on both sides. In order to
Electronics Forum | Wed Oct 17 02:53:36 EDT 2001 | dszeto
The fine pitch QFP is a 240 pin one being loaded with other components on a 2.0mm thick FR4 PCB. There are 6 of this Qfp's on this PCB showing the same charactristic of bowing therfore the solder fillets are vary from the center to the end of the pa
Electronics Forum | Sat Feb 01 09:01:14 EST 2003 | davef
It sounds like your board is "dome shaped", some call it "cupped". If so, this is more of a twist than a bow. Before moving on, if we receive a board that is so torqued that we can't figure-out how to measure it, we reject it. Go back to your TM-
Electronics Forum | Thu Aug 14 16:36:45 EDT 2003 | Hussman
Anyone using these 2010 resistors? We just tried them and they bow like crazy during reflow. Not very good looking. Profile meets manufacturers spec. The part solders and works fine, but I'm a little concerned about putting anything on a board th
Electronics Forum | Sun Aug 24 15:00:46 EDT 2003 | Handsome zhang
I am placing a plastic Cypress, 256 pin BGA on a > small assembly, and I cannot stop the corners > from bowing. I've moved my profile up and down > with no results. Any suggestions? Hi mike I am a staff of smt in ASUS(TAIWAN),I have a large in
Electronics Forum | Thu Sep 16 07:07:34 EDT 2004 | C Lampron
Hello Chris, "It sticks up about 3/8" or so above the surface of the board." Is this over the ridgid portion of the PCB or in between? Is it possible to create a support fixture for printing that has relief that will allow the flex to bow downward i
Electronics Forum | Thu Jan 18 19:16:42 EST 2001 | slowe
I am having problems with D-Packs shifting during reflow. Does anyone know of a good aperture design to solve this problem ? Possibly bow tie.