Electronics Forum | Tue Mar 30 05:27:06 EDT 2010 | accuspares
Hi, Can you tell me at what point in the print cycle the error happens and if it consistently happens at the same point? The machine has two crash beams running down either side of the machine as a safety measure to ensure the table is down before
Electronics Forum | Tue Jul 19 08:26:46 EDT 2016 | pavel_murtishev
Aleksander, The answer is no. Solder deposit being printed is 80um-150um in height depending on PCB design what is two times higher than any track covered by solder mask. Molten solder will merely center the component. QFNs are prone to soldering
Electronics Forum | Sat Jul 24 00:04:55 EDT 1999 | Scott McKee
| | | There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not perform
Electronics Forum | Fri Jun 04 17:44:20 EDT 2021 | dwl
The hardest part was convincing management of the need for a stencil cleaner in the first place. Cleaning by hand using IPA and a lint free cloth just leads to clogged apertures and print defects. BTW, lint free cloths leave behind a lot of lint.
Electronics Forum | Wed Feb 09 12:28:58 EST 2005 | Valerie
We have been pretty successful with screen printing glue, however the smallest component we now glue is a 0805. We had many problems using our Gemini II to put down glue dots for a 0603, so we altered the pads to do double-side reflow. As our own int
Electronics Forum | Tue Jun 05 14:38:55 EDT 2001 | pteerink
You would be better served to check your print quality as you run. Any problems caused by dirty stencils ( plugged aps etc ) would show up right away as a defect. Search the forum for more on this subject. I seem to recall the same subject coming up
Electronics Forum | Mon Sep 23 18:11:10 EDT 2002 | steveb
On an assembly reflowed in air saw the same thing: 0201's with a grainular solder joint, but 0402's and above with perfectly formed joints. Reflow profile all within acceptable tolerances. Reflowing in nitrogen solves this problem, but increases t
Electronics Forum | Fri Jun 23 10:10:15 EDT 2006 | Gman
Some amount of voiding was always seen on sites where solder paste is printed. These voids are much smaller. However the site where a flip chip is flux dipped has never had problems with voiding. Macro voids (and huge ones at that)across the board s
Electronics Forum | Sun Mar 01 15:52:13 EST 1998 | Earl Moon
| From several months I am investigation about the VOIDS PERSENCE and his important as reliability. | One question now is : | It is possible that on the BGA components the voids are already present into the balls, before the mounting on the pcb ? | I
Electronics Forum | Tue Jul 09 15:20:19 EDT 2002 | pjc
When you look at the capabilities of Combo machines they tend to sacrifice performance when compared to separate X-ray and AOI machines, meaning they don't do either the X-ray or AOI operations as well as a machine that was designed to do only one. A
