Electronics Forum | Thu May 21 22:07:47 EDT 1998 | Mike Konrad
I am a former employee of a drag soldering machine manufacturer. For years they attempted to devise a method of soldering surface mount devices via the drag soldering machine. Bridging was the largest problem along with component damage due to exce
Electronics Forum | Fri May 22 22:13:27 EDT 1998 | G. Henning
Thanks for the advice. We are experiencing only limited success with SMT on the drag. Problems are indeed bridging and misses on the smaller discretes. Works well on PTH as long as the pitch is not too tight. I'll have to justify a new machine. Rega
Electronics Forum | Thu May 21 22:20:18 EDT 1998 | Earl Moon
| I am a former employee of a drag soldering machine manufacturer. For years they attempted to devise a method of soldering surface mount devices via the drag soldering machine. Bridging was the largest problem along with component damage due to ex
Electronics Forum | Fri Apr 24 20:33:06 EDT 1998 | D.Lange
| Looking for anyone who has experience with high temperature soldering. Need to determine why solder joints are failing. Thermocycling of unit is -40C to +140C, 30 minute dwell time, 10 sec. transition time | Your help is appreciated | Ed Holton |
Electronics Forum | Thu Jan 24 09:53:56 EST 2002 | davef
You didn�t tell us about your solder, wave temperature profile, or the distribution of the problem. So, let�s assume the solder is near eutectic and the problem is wide spread. Wolfgang makes good points. So, let's talk a different tact. When we
Electronics Forum | Mon Jul 01 20:42:54 EDT 2002 | davef
Comments [questions] are: * It�s strange that an uggie ol� SOIC, 50 pitch, BIG honkin� solder pad, kinda thang is failing. Sumpin aint kosher, yano? * Where is the failure occurring [ie, lead to pad, pad to board, etc]? Talk about the breadth and di
Electronics Forum | Tue Jul 30 17:47:50 EDT 2002 | davef
Dewetting: Solder does not adhere to lead or land, caused by: * Poor solderability of lands. * Poor solderability of leads. * Solder paste integrity. * Lead plating integrity. Need more information, please: * What is dewetting [ie, component, pad, e
Electronics Forum | Wed Jul 31 17:25:39 EDT 2002 | sueph
Dave, thanks for the reply. These boards have metal plating covering 99 percent of both primary and secondary surfaces. The only places without the metal plating are the extreme outer edges and about an 1/8 inch surrounding the plated holes. We do
Electronics Forum | Thu Dec 05 11:04:27 EST 2002 | slthomas
They're IR, bottom side only. Frankly wave solder is not my forte (there are those that would claim nothing is), but I've personally been tasked with developing a process to do reliable, high volume bottom side SMT, so I'm drawing a lot from the tec
Electronics Forum | Mon Jan 27 14:16:46 EST 2003 | russ
i have done this thousands of times. You are correct about no preheat, however it never seemed to be any issue for us. You do have to make sure that you do not expose any SMT comps. to the solder or they will become heat stressed/fractured. Connec
