Electronics Forum | Mon Mar 27 20:52:22 EST 2000 | Dave F
Marc: In printed circuit board fabrication, fabricators place sheets of prepreg between each pair of glass cores. They stack these layers into books. As they heat and press the books, the sheet melts into an epoxy glue. The thickness of the prepr
Electronics Forum | Wed Mar 22 17:28:13 EST 2000 | Steve Harshbarger
Donnie, It's funny you ask this question. I just last month was at a company doing exactly what you are asking (Alpha 310 flux with infrared heating). They were successful, but they had 2 important things going for them. 1) A spray fluxer that wa
Electronics Forum | Wed Mar 01 17:13:15 EST 2000 | Dave F
Sorin: Formulas for calculating heat dissipation of traces don�t seem to provide practical results. But there are some wonderful tables and graphs that will meet you needs. You may need to do some finagling when calculating vias and through holes,
Electronics Forum | Mon Feb 28 19:36:39 EST 2000 | Tony
I work for a contract manufacture of PCB's, we are also in the BGA rework business. We see all kinds of different size boards, as well as different types of BGA's and micro BGA's. We selected the Conceptronics Freedom 2000 over the Air Vac and SRT. T
Electronics Forum | Fri Mar 10 12:12:55 EST 2000 | Russ
Casey, I will start with the lack of thermo-couple control - The unit I have is based on time and temp. exclusively. What happens when a cold board gets reworked vs. a hot board? No bottom side preheat, the heating is very localized to topside a
Electronics Forum | Sat Feb 19 05:07:28 EST 2000 | Dean
I'm not exactly sure of your problem...but I'll give it a shot. I assume the screw is on the solder side of the board. If you wave solder the screw the head will fill in with solder. Try a water solouble mask or peelable laytex mask over the screw
Electronics Forum | Mon Jan 29 11:52:55 EST 2001 | blnorman
We have been using a VOC-free, no-clean flux on our boards that we conformally coat with no problems. We're using both a UV cured and a heat cured Silicone conformal coating. One thing to beware of is inhibition in the silicone. We found that out t
Electronics Forum | Wed Feb 21 21:21:10 EST 2001 | davef
Gary: It doesn't matter what you use to cure your glue. SMA adhesives are thermosets. This means they become hard on cure and this is not reversible. A couple of things go on with SMA adhesives when you heat them. * Their rheology is temperature
Electronics Forum | Thu Mar 01 10:10:30 EST 2001 | Stefan Witte
Angela, besides the sense or non sense of six sigma and related meetings, you will have to break down the component feeding issue into several sections, which are all impacting the feeding reliability. 1. Component dimensions 2. Tape size 8, 12, 16
Electronics Forum | Tue Mar 27 09:06:10 EST 2001 | dblsixes
We have tried to adjust the upper and lower heaters. We have a dillema in this area however. The power supply portion of the assembly has thermal vias in the solder pads underneath larger pads. We have a problem with solder wicking through these h
