Electronics Forum | Tue Apr 01 19:21:25 EST 2003 | Myu
I'm a user changing over from WS-609 to WS-709. WS-709 has less voiding problem and longer stencil life than WS-609. Ws-709 has a less foaming during washing process. Thanks, Myu
Electronics Forum | Wed Apr 02 10:51:17 EST 2003 | kmorris
Myu: Did you have to change your reflow profiles when you changed from 609 to 709? What ramp rate & time over liquidus are your profiles at?
Electronics Forum | Tue Apr 01 19:45:48 EST 2003 | mk
Try checking into ssd www.sipad.com No clean process for the whole board. Contamination from paste is removed before you get the boards. http://www.sipad.com/Motorola/MotorolaFlipChip.htm mkehoe@sipad.net
Electronics Forum | Tue Apr 01 19:36:02 EST 2003 | iman
from my humble experience : 1) check if there is nickle contaminate in the gold bath? shd have report data from the PCB fab house. 2) check if your production did 48hr bake at 125degC, IF the BGA did not come in its "original" MSD cozy packaging.
Electronics Forum | Tue Apr 01 13:17:49 EST 2003 | cyber_wolf
The problem is that there are also SOT23's present. I would use a .004 or a .005 stencil, but I don't think that the dots are going to contact the bottom of the larger packages on a thinner stencil. ...Thanks for the input.
Electronics Forum | Tue Apr 01 18:21:48 EST 2003 | slthomas
I've never printed adhesive but I assume that aspect ratio still plays a part with release. Maybe that .006" is just to thick to get good release. Can you step your stencil down from .006" to .004" or .005" for the 0402's?
Electronics Forum | Thu Apr 03 18:10:08 EST 2003 | Print Master
0402 Adhesive printing is possible with thicker stencils in order to allow mixed component technology. We have successfully printed 0402's with a 0.008" thick SS foil. Total material release is not achievable at this thickness, but not required u
Electronics Forum | Tue Apr 01 15:36:43 EST 2003 | ssnow
I would like to know if there is any semi automated PM scheduler to aid in prevenitive maintence. Via excel, Outlook,Access or any specific software targeting this subject. Thanks.
Electronics Forum | Fri Apr 04 05:04:49 EST 2003 | iman
10Mohm DI washing. On the paste supplier recommendation, we sent sampling boards for Ionic Contamination test with specs
Electronics Forum | Fri Apr 04 10:02:20 EST 2003 | rdr
Do you reflow both sides of the boards before washing? Sometimes these white residues occur from "burnt" flux. we see this from time to time especially when using hot air and liquid flux. Russ
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