Electronics Forum | Mon Aug 18 10:42:04 EDT 2008 | floydf
We are in the process of preparing for a new board that requires paste in hole processing. The hole is a .020" via, and our customer wants it filled with solder, but not bulging past flush. For printers,we use a DEK 249 with a squeegee, and a DEK 260
Electronics Forum | Fri Jun 07 05:19:23 EDT 2019 | gregoryyork
dont usually see this unless the Rosin hasnt been hardened due to low reflow or excessive pressure on blades squeezing flux out so you have flux rich areas. Are these boards also flow soldered?
Electronics Forum | Tue Jan 21 13:51:19 EST 2014 | rgduval
Armando, Is the problem in the same spot on the board with every run? If so, there might be something about that particular location that is part of the cause (ie. ground or power plane connection). It sounds like you're seeing blow holes, or insu
Electronics Forum | Wed Dec 08 11:26:04 EST 2010 | davef
3 Printer Area Conditions * As stated earlier, heat and humidity are damaging to solder paste. Ideally, the printing area should be maintained at 40% - 50% relative humidity and 72°- 80°F (22-26°C). In addition, no air (cool or warm) should blow dire
Electronics Forum | Thu Oct 31 11:08:12 EST 2002 | soupatech
Being very new to SMT I won't assume I know what the problem is but.... I had lots of air pockets in solder joints, 95% of the boards. Everyone I spoke to thought it was a problem with my process but when one board was sent to our supplier they admi
Electronics Forum | Tue Mar 24 11:20:18 EST 1998 | Earl Moon
| Anyone have an idea how small a via must be to inhibit significant solder volume escaping into the via? Typically, micro vias are drilled and plated to about .003" diameter. To avoid significant solder "drain off," they should be drilled as shallow
Electronics Forum | Wed Apr 21 14:29:58 EDT 1999 | joe devaney
| Does anyone have any experience with soldering 50mil pitch BGA's that have a via in the pad, the size is .012 The via will be masked off on the bottom side of the board. Need to know what precautions or problems if any I might encounter. The proces
Electronics Forum | Wed Mar 25 19:41:01 EST 1998 | Earl Moon
| We have successfully put .016" vias in .030" pads. | There is no drain off with .030" solder balls, since | the actual volume in the .002" depression is low. | We did notice random bubbles where, apparently, the | solder reflowed and trapped the a
Electronics Forum | Wed Mar 25 16:38:21 EST 1998 | Steve Joy
We have successfully put .016" vias in .030" pads. There is no issue with .030" solder balls, since the actual volume of the .002" via in pad is small compared to the ball+solder paste volume. We did notice random bubbles where, apparently, the sol
Electronics Forum | Wed Mar 25 16:36:10 EST 1998 | Steve Joy
We have successfully put .016" vias in .030" pads. There is no drain off with .030" solder balls, since the actual volume in the .002" depression is low. We did notice random bubbles where, apparently, the solder reflowed and trapped the air in the
