Electronics Forum | Wed Sep 07 09:34:15 EDT 2005 | PWH
Does anyone know of an IPC standard that deals with drilled holes in a PCB in relation to pad location? We have a PCB where the holes are very close to (through the edge of in some cases) a SMT component pad on a PCB.
Electronics Forum | Thu Sep 08 05:09:57 EDT 2005 | dougs
Sorry, i dont have access, it was a few years ago i last worked on GSM machines.
Electronics Forum | Fri Sep 09 03:51:57 EDT 2005 | geb
Thanks for your help. Yes it is a VME630 Lantern vision system. I'll try swapping the card with the one in the other machine.
Electronics Forum | Thu Sep 08 08:54:09 EDT 2005 | Slaine
if the problem is wetting change the flux type. have you tried adjusting the temperature of the wave? if your getting 100% wetting id decrease the wave temperature, or try a flux that is less active.
Electronics Forum | Thu Sep 08 09:47:20 EDT 2005 | lupo
I will try with temperature 255 C degrees. The wetting force vs. solder temperature for SAC305 is more than 265 C degrees (the temperature of trials). Thanks for the advise. Regards
Electronics Forum | Fri Sep 09 10:43:58 EDT 2005 | ???
sounds like the part is being picked up on its side....which means.......it could be.... 1. pickup not taught correctly -- X-Y- or Z 2. head to camera calibration is needed 3. or least likely....feeder problems
Electronics Forum | Fri Sep 09 11:01:14 EDT 2005 | rob
If the tombstoning is thermal (occuring during reflow) then try slightly reducing the stencil apertures so there is less the paste on the pads, reducing the forces acting on the component. Also take a look at the cooldown profile & making it more
Electronics Forum | Fri Sep 09 11:21:57 EDT 2005 | gregcr
thanks for the feedback, The part is not on its side, it is placed properly before the reflow. We are starting the process of changing the stencil apps. thanks
Electronics Forum | Fri Sep 09 11:37:27 EDT 2005 | ???
Try home-plated the stencil apertures, and make "V" shape home-plated outside edges of two pads instead of between two pads.
Electronics Forum | Fri Sep 09 14:03:06 EDT 2005 | Mei
Nomorely the V-shape home-plated apertures look like two opening mouth facing each other. But this time just opposite way. And make 30% home-plated. Hope you can understand.
