Electronics Forum | Wed Nov 09 11:18:39 EST 2005 | Beef Kakes
Cracked components will occur when the component is stressed. The only way to stop this is to not stress the part when removing the score. This can be done by fixturing the board top and bottom so it doesn�t bow when breaking off the breakaway. Vi
Electronics Forum | Wed Oct 26 16:47:17 EDT 2005 | jdengler
I have never heard of heating the board for separation. You may want to try some of the following. -Using a roller cutting type depaneler helps reduce the stress. -Using a combination of routing in areas with components near the edge and v-score th
Electronics Forum | Tue Sep 19 14:40:13 EDT 2000 | Erick Russell
It is always a good idea to heat the entire board to 100C to 140C prior to reflowing the site to be reworked to reduce warp and localized stress. (Thermal uniformity of the preheater is key here). For a BGA, the laser is programmed to heat only the
Electronics Forum | Fri Aug 11 22:50:57 EDT 2017 | heros_electronics
Anyone who knows how to prevent such flaw? Tombstones are those lifted components from one sides. This results in costly and time-consuming amounts of touch-up and re-work after the assembly is completed. For the customers, this extra work translate
Electronics Forum | Sun Aug 13 22:26:01 EDT 2017 | dawson
Anyone who knows how to prevent such > flaw? > > Tombstones are those lifted components > from one sides. This results in costly and > time-consuming amounts of touch-up and re-work > after the assembly is completed. For the > customers, this e
Electronics Forum | Wed Jul 15 13:33:56 EDT 1998 | Don Welling
I am looking for information on the amount of stress a component sees during the depaneling process. I am currently specifying a new piece of depaneling equipment and I have not found any studies that quantitatively compare the amount of stress diff
Electronics Forum | Thu May 22 18:47:12 EDT 2003 | russ
I would assume we are talking about a radial leaded electrolytic cap? We use Electronic grade RTV (Dow corning 3145). It sticks good and can be removed if necessary. It is also pliable so you don't have to worry about CTE or other stresses that may
Electronics Forum | Tue Jan 04 19:55:46 EST 2000 | Rob Thomas
Hello Yosef, non woven aramid reinforced pcb's are used where is a need for low CFT (coefficient of thermal expansion). Traditionally aramid pcb's were used in military applications in order to reduce the stress/failure rate of solder joints during
Electronics Forum | Tue Jun 02 14:32:58 EDT 1998 | Chris Fontaine
We have experienced poor adhesion of acrylic conformal coating to plastic bodied IC�s. The observed symptoms of this are a blistering or lifting of the coating at the surface of the component, although peel testing has revealed that this is not alwa
Electronics Forum | Fri Jul 29 19:12:30 EDT 2005 | Jason Fullerton
In the true sense of the term, tombstoning can only occur during reflow. Now, if your solder joints are cracking during thermal cycling and opening on one end you still have a problem - it just isn't "tombstoning". What laminate are you using on yo
