Electronics Forum | Mon Feb 21 08:39:10 EST 2005 | pemnut
There are so many variables to this. It could be paste, pad size, contaminated components-pads, placement speed, component thickness being wrong in the program, dropping parts into the paste instead of placing them, component recognition ploblems. Is
Electronics Forum | Thu Feb 17 14:43:22 EST 2005 | JB
I agree with the stand alone option. That way you can sample PCB's from different stages ( print, placement post reflow) In a controled process, after reflow inspection would be ideal.
Electronics Forum | Fri Feb 18 11:25:14 EST 2005 | davef
It's weird that it would be just 0805. When we see this it relates to a single part number and it goes way after a time. We use a Humiseal 1B73. I've emailed you the contact for a person that is very knowledgeable on conformal coatings.
Electronics Forum | Mon Feb 21 11:25:41 EST 2005 | aj
thanks for all the replies. we clean our Dek Stencils after use with IPA. What gloves do you guys use when cleaning stencils? I have found some info. relating to Latex Gloves as been a possible cause..
Electronics Forum | Sun Feb 27 06:04:29 EST 2005 | raj_nz
WE have this old YV112 PICK AND PLACE machine that we put it together ourselves.the problem is after loading the file the OS does the PCB data check ,it keeps on looping to pcb data check and doesnt go to next stage. any suggestions??/
Electronics Forum | Wed Mar 09 12:18:55 EST 2005 | Greg
Hi, How do you validate a pick and place machine's performance after installation? What standard will I use to track placement accuracy? what other factors do i need to look at? thanks and regards,
Electronics Forum | Sat Mar 12 10:14:48 EST 2005 | emeto
Thanks for your answers. What I am thinking is after reflow AOI doesn't make sense. May be it is helpful only before that - show you the problems , may be repair station or something like that. What do you think about that?
Electronics Forum | Thu Mar 17 22:14:42 EST 2005 | Chua
Hi Davef, Thanks for your advise...... We are running no-clean process. If there is white residues after few days.....is it cause by those excess flux. Thanks
Electronics Forum | Thu Mar 17 10:30:06 EST 2005 | davef
This happens. You may need to put a dot of chip bonder on the corner of the floating QFP after first pass. What size are the QFP that are moving?
Electronics Forum | Thu Mar 17 10:34:34 EST 2005 | Rob
Or... If you have an inline glue dispensor, after printing put a glue dot in the centre of the footprint & this should hold it. Rob.
