Electronics Forum | Wed Jun 05 14:43:33 EDT 2002 | davef
Steve, As a reason for cleaning no-clean flux res: Well, maybe some of Por's products / customers can live with NC flux res, while others cannot accept it. So, rather than running two fluxes Por finds it simpler to clean the NC flux res. For us,
Electronics Forum | Thu Jun 06 02:52:42 EDT 2002 | ianchan
Hi mates, just my 2cents worth... some folks (like us) have product runs that have BGA using no-clean, coupled that with Class3 IPC-A-610 specs, topped with aerospace/military customer defined specs. we end up cleaning NC with a degreaser machine w
Electronics Forum | Tue May 28 13:14:31 EDT 2002 | zanolli
Hello Mark, I'll assume that you are currently wave soldering and would like to eliminate that operation by using pre-forms or press-fit connectors. Solder preforms or solder flux bearing connector leads usually do not require any hole size changes,
Electronics Forum | Wed May 29 08:43:12 EDT 2002 | zanolli
Various solder metal supplies sell pre-forms as loose individual shapes, usually donuts. The loose performs then are placed on the connector leads. If you have any volume at all, you would want to look at a �shake table� that would vibrate a batch of
Electronics Forum | Wed May 29 15:29:41 EDT 2002 | zanolli
Hello Peterson, If the contact tails protruded enough on the underside of the PCB, then you could do a "reverse" press fit. I do not believe that to be the case with the VHDM. Placement equipment is out of my bailiwick but; Usually small SMT connec
Electronics Forum | Tue Jun 04 17:10:13 EDT 2002 | davef
First, �flash gold� is very loose language. It means different things to different people. �Flash� gold is a thin coat of immersion gold. Imm gold self-limits at ~0.3um[12uin]. And fabs put-down �flash� prior to electroplating thicker gold for wi
Electronics Forum | Tue Jun 04 20:34:28 EDT 2002 | russ
Jason, Excessive thermal ramp rates, misprints, improper pad design, paste type, placement pressure, all can cause solderballs. Do the pads on this board meet IPC 782 criterias? I have found that too much pad underneath component can cause this. A
Electronics Forum | Tue Jun 04 12:54:00 EDT 2002 | Bob
Hi, We are manufacturing a small PCB with large areas of gold plating. We experience from time to time what appear to be solder splashes on the gold areas. I do not believe the contamination to be from "outgassing" due to the distance from the dep
Electronics Forum | Wed Jun 05 15:09:44 EDT 2002 | cyber_wolf
I have seen this happen before it has been my experience that even one tiny sphere of solder form your solder paste will melt and spread out on your gold fingers. The particles are so small that they are not visible to the naked eye. If operators ha
Electronics Forum | Thu Jun 06 07:28:30 EDT 2002 | cyber_wolf
It has been my experience that the only thing(s) that will ever cause this is: 1. Operators with paste on their hands. 2. Paste on the screen printer tooling. 3. Paste on the bottom of the stencil. Even very very small amounts of paste on the gold fi
