Electronics Forum | Fri Apr 04 14:49:51 EDT 2008 | tombstone
Flux seperation is a common problem observed due to expiration of paste. The symptom is a yellow layer of flux when you open the jar. Excess flux separation will cause priting problems such as smearing and slumping.
Electronics Forum | Tue Jan 16 20:44:07 EST 2007 | davef
Bridging Causes: Insufficient flux, Excessive pre-heat, High conveyor speed, Solder contamination Look here: * http://www.smtnet.com/library/files/upload/Reflow%20Wave%20Poster.pdf * http://smt.pennnet.com/Articles/Article_Display.cfm?Section=Archi
Electronics Forum | Tue Sep 25 09:57:40 EDT 2001 | nwyatt
In regards to your last question, - problem is failures and most think it is due to too much flux - we apply flux with a brush - amount applied depends on the operator applying it - the flux is very thick and will hold the part in place before reflo
Electronics Forum | Sat Mar 25 16:05:13 EST 2006 | loz
Hi, sounds unusual if your profile is accurate that you have so many residues. Had a similar problem before with no clean flux and with various flux manufacturers, and all residues were down to excess flux. This does not help your case though. How a
Electronics Forum | Wed Apr 28 15:08:10 EDT 2004 | russ
This could be a long shot but here goes. I have found that if flux is applied in excess that it will actually "move the solderballs" during reflow. I have actually seen where the balls are completely outside the package and oviously there are short
Electronics Forum | Mon Sep 24 20:38:27 EDT 2001 | davef
Mike's comments are well taken. Your technique works fine with BGA, but uBGA are less forgiving. Again, let's take about: * Specifics of the problem. * Amount and method of applying flux. * What's holding the uBGA in-place before the solder ball an
Electronics Forum | Fri Sep 28 16:51:41 EDT 2001 | pcmarch
I have had success by applying the paste flux with my finger, using a finger cot and spreading it on the PCB. This seems to put it on more consistently than using a brush.
Electronics Forum | Fri Apr 05 15:25:14 EST 2002 | davef
Spray fluxers: Where does the excess flux [that does not glomb on the board] go after being sprayed at the board? How do various spray fluxers [wave solder machines] route �used flux� differently?
Electronics Forum | Tue Mar 30 07:20:20 EST 2004 | davef
If you can rub it off, it's unlikely to be a solder mask problem. Try the "excess flux, flux contamination, solder contamination" angle.
Electronics Forum | Thu Aug 26 22:32:04 EDT 2004 | Indy
Hey, We have introduced a Cleaning Pen from Chemtronics. It removes excess flux after touch up.. This way the operator doesn't have to go everytime to the cleaning room.. Indy
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