Electronics Forum | Mon Nov 13 14:58:56 EST 2017 | davef
Determine the origin of the solder * Sloppy paste printing technique * Lax stencil underside cleaning practices * Sloppy misprint cleaning practices * Poor part placement practices creating solder balls * Poor material control allowing solder p
Electronics Forum | Mon Mar 26 19:22:22 EDT 2018 | tey422
First of all, shouldn't allow SMT operators to edit/create recipes, only grant access to the well-trained only. You will put yourself at risk if you don't have good process rule of oven recipes. Newer oven models should come with software that has m
Electronics Forum | Tue Mar 20 04:40:15 EDT 2018 | rob
I've seen them down at 2 metres in the past, but usually only 4 zone. from memory Electrovert used to do a small 5 zone with pin chain - Infraflow 500 or something. To be fair, even small one line CEMs usually have a decent oven as you need to be a
Electronics Forum | Sun Mar 25 08:45:00 EDT 2018 | jacobidiego
Normally some random components of size 0604 or below and may be due to a thermal mass being close like a transformer or AC electrolytic caps. We tried changing fan speed, but this will change the thermal profile and avoid the thermal mass from bein
Electronics Forum | Thu Jul 26 04:26:59 EDT 2018 | Robl
Hi VChauhan, I'll preface this by saying I am no DaveF. Voiding can occur when the flux in the paste boils and vapourises, the expanding vapour needing somewhere to go displaces the paste. So... what we have done in the past: 1) Step the stencil d
Electronics Forum | Wed Aug 22 16:41:09 EDT 2018 | emeto
To all good suggestions I will add a few other thoughts: 1. Check PCB design(attached). THis mask clearance there is designed so you have some gas escape plan- verify if your PCB design follows that. 2. You can have a long soak reflow profile to re
Electronics Forum | Tue Aug 14 13:54:57 EDT 2018 | etmpalletguy
Vlad, Reduce your aperture opening in the stencil, this will give the stencil a good seal around the specific area of concern. In a wave solder environment, solder balling top or bottom surfaces in a wave pallet is caused by excessive flux burning o
Electronics Forum | Fri Aug 24 11:58:18 EDT 2018 | cupet
Hello davef, thank you for your reply. What do you think about the footprint for the diode on the first picture where the component is not assembled? There is good wetting on one pad of footprint and the other pad has bad wetting. This problem is not
Electronics Forum | Fri Aug 24 12:46:55 EDT 2018 | cupet
Hello, I have been using this reflow and reflow profile for the last four months. This problem occurs sporadically. Perhaps 95% of produced PCBs are good, without problem. We order PCB's from a Chinese supplier in smaller batches that we use right no
Electronics Forum | Wed Oct 17 12:05:08 EDT 2018 | charliedci
We had a selective solder installation tech raise the connector body off of the PCB slightly with a spacer to allow for a visual inspection to verify the process/profile. A few years back we invested in a large enclosure X-ray with a manipulator arm
