Electronics Forum | Thu Feb 15 16:58:11 EST 2007 | flipit
Phil, I used to print solder paste on 2" X 2" and 3" X 3" 96% Alumina substrates all the time. I used standard solder printers and stencils. Screens are difficult to use and don't print well. You can use a stencil on a DeHart, CW Price, or AMI Pr
Electronics Forum | Sun Jan 25 17:40:16 EST 2009 | cuperpeter
Hello All, I have a problem with nonwetting Au finish after second cycle of reflow soldering doublesided boards. Solder nonwetted pcb pads (is wicked to component terminations) Either these pads or some of non component pads became discoloured from
Electronics Forum | Mon Dec 28 08:51:45 EST 2009 | jax
What solder are you talking about and what reflow method are you using? High Melt Alloys: SN96 (Sn96/Ag4 or Sn96.5/Ag3.5) - Simliar to SAC305 although normally uses Rosin based flux that can required more extensive cleaning. Pb85 (Pb85/Sb10/Sn5) -
Electronics Forum | Mon Mar 08 05:03:24 EST 2010 | grahamcooper22
Hi, I fully agree with isd.jww. The difference in the solder joint appearance of the 2 joints highlighted could be down to a few reasons...reflow profile (I know you've checked, but have you stuck a thermocouple on this actual joint ? ), contaminatio
Electronics Forum | Tue Sep 18 21:37:06 EDT 2012 | vergara1
Hi Manoel, I want to make sure I understand what you are talking about; reading the reply,along with your replys it almost sounds as if we are not talking about the same thing. In your picture I'm seeing a SMT diode correct? You are talking about th
Electronics Forum | Mon Jul 24 22:50:43 EDT 2017 | dawson
In fact, we can solve this problem easily. AOI only check whether the IC is soldered well. But we can ask our technician to make a test first to control the reflowing temperature and time. 1. using tool to test the temperature between the bottom IC
Electronics Forum | Thu May 03 17:33:20 EDT 2018 | dleeper
Solder paste selection can have a huge impact on size and quantity of voids. Talk to a few suppliers and ask for their recommendation on low voiding formulas. Pick a few of your top candidates and then perform a DOE to see who has the best result. S
Electronics Forum | Tue May 19 12:29:59 EDT 1998 | Richard Jackson
| Richard, | You may be encountering solder paste contamination | on the assembly during the printing process. Solder | will reflow on tin/lead plated lands therefore invisible. | If you are washing the assembly prior to inspection | then you are
Electronics Forum | Thu Oct 09 11:57:14 EDT 2008 | hussman
Why not build with a leaded paste or solder pot? You'll have more than 3% lead after solder. Who cares about before solder - any testing will be done on the finished product.
Electronics Forum | Wed Aug 18 11:12:04 EDT 2010 | davef
So with your mounting frustration in your inability to zero-in on the factors that drive your solder balling, are you thinking that maybe you need to bite the bullet and design a experimental study to help isolate the key drivers to your solder balli
