Electronics Forum | Mon Feb 19 13:04:17 EST 2001 | billschreiber
The ultrasonic frequency used in today�s stencil cleaners is usually a 40 kHz �sweep� frequency (also used on semiconductors and other sensitive cleaning applications). This frequency is not low enough to cause stencil damage (the lower the frequen
Electronics Forum | Thu Jul 16 16:56:02 EDT 1998 | Doug Nebel
| Howdy 2, | I am using my first DEK GSX PRINTER. Looks and acts good so far. Who know what - good, bad, or in between? Just want to get the facts from those who know. | Earl Moon We have had our 265 GSX a little over 2 years. Print quality has bee
Electronics Forum | Fri Jun 16 06:24:43 EDT 2000 | Wolfgang Busko
Hi Todd, it might be a philosophical question if soldermask between finepitch pads is prefered or not. That should depend on the capabilities of a particular site and their experience. We actually prefer soldermask down to 0,4mm pitch and don�t have
Electronics Forum | Mon Sep 13 04:11:27 EDT 1999 | Earl Moon
| | hello | | | | having a problem with one customers bare boards not matching my stencil apertures. i design stencils based on gerber data and reduce up to 15% on some pads. do some board houses reduce pads after receiving gerber data???why would
Electronics Forum | Fri Jun 15 09:16:46 EDT 2001 | adam
Thanks Dave. About your second comment, the issue is placing BGA connectors mirror image (male, and female), the connector sometimes shifts during placement before reflow. we are using a six mil stencil for both sides with minimum paste deposit. a
Electronics Forum | Tue Aug 31 02:15:12 EDT 2004 | AOI Solution
I need to address the issue for colorful display on solder joints, for whoever researched on this machine, no one can deny it is a smart feature for visual assistance. however, it is still Mono color "gray scale" algorithm. it basically "paint" the i
Electronics Forum | Mon Sep 17 03:59:52 EDT 2012 | stivais
Hi guys, We have an interesting case we haven't seen before (see the picture below) http://postimage.org/image/lu2f4ae55/ Solder balls form on unpopulated pads after reflow. 1. Reflow profile is fine. 2. Stencil thickness / paste volume is also f
Electronics Forum | Fri May 31 12:50:42 EDT 2013 | spoiltforchoice
Is this a "thermal balance" issue? In the 2nd image you have a group of pads blobbed together as one giant pad. IMHO this is a bad idea, QFN's rely heavily on the magic of your paste and good PCB design to get good alignment. When your solder paste i
Electronics Forum | Fri Jul 07 12:44:49 EDT 2017 | tsauve
The problem is registration between the stencil & the smallest pads on the 5 substrates. Using SPI s/w I can overlay the paste layer over the PCB image to determine stretch/shrink. Our worst case was shrinkage of 10.2mil on a 5-up 300mm panel - small
Electronics Forum | Thu Jun 20 23:28:15 EDT 2019 | SMTA-David
How can I upload image to this forum? I can show you the pad layout. I am thinking maybe too much solder. I used 0.16mm thick stencil but notice many us 0.12mm thickness. Also, cream layer is 100% of pad surface, I know for fine pitch parts it is r
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