Electronics Forum | Fri Mar 14 04:42:24 EST 2003 | emeto
Hi, About Thombstone defects: 1.Placement accuracy-main reason 2.Soldering-should be right on pads.The print should have regular shape.The quontity of the solder on both pads on one component have to be equal. 3.Reflow: the profile have to be made v
Electronics Forum | Fri Apr 11 16:07:08 EDT 2003 | daanterstegge
I'd say your profile is about right, assuming these are values that you measured in the balls of this BGA and not elsewhere on the board. If you want a more shiny joint than use a nitrogen oven or experiment with various solder pastes, but why the he
Electronics Forum | Wed Apr 16 10:45:16 EDT 2003 | Takfire
Recent cross-section analysis for a customer complaint revealed voiding in the solder fillet. In some cases, the remains of outgassing were also observed. During the failure analysis, we also observed failures where the solder fillet wicked on the
Electronics Forum | Mon Apr 12 10:39:48 EDT 2004 | Ron Herbert
Correct preheating of the assembly is critical. Check with your flux manufacturer regarding the recommended topside pcb temperature as it enters the first wave. It is important that this temperature be achieved without burning the flux on the bottom
Electronics Forum | Thu May 06 19:13:24 EDT 2004 | Greg York
Watch your dwell time especially if larger components. Problem is normally associated with lower temp as well as insufficient flux coverage with larger massed boards or ground planes. Try to hand spray a board to check that fluxer operation is OK. If
Electronics Forum | Thu May 06 20:11:46 EDT 2004 | gregoryyork
It does sound like your leads are to long, speeding it up will reduce volume on lead and most will wick up the joint but when slow excess solder is left as long leads will have little flux left to aid drainage when it leaves the wave, thus giving a s
Electronics Forum | Wed May 12 10:21:37 EDT 2004 | solderpro
having a bad morning there Gregory.... take it easy, where you from? who's company? Do you rep this firm or is this yours? I surely did not mean to disrepect your input, but I am sure there are things you need to learn that are not in the operators m
Electronics Forum | Wed May 12 12:11:54 EDT 2004 | solderpro
Bruce, regards to all who are trying to help and have great input, with those type of lead length, I would be very impressed to see you get rid of the problem, and as the others said, no clean in a foam fluxer, not good but workable.... the real issu
Electronics Forum | Mon Jun 16 13:57:48 EDT 2003 | James
Could anyone give me a basic profile temperature settings for a conceptronics 7 zone oven and speed? I have the first couple of zones ramped up to get to the soak temperatures. Is this correct or should I start out with low temperatures and graduall
Electronics Forum | Tue Jun 24 09:42:52 EDT 2003 | stepheno
The temprature for the first zone should be less as the PCB entering the oven from the ambient shop floor temprature would suffer a thermal shock from a higher temp. Experience must be gained from profiling a board with thermocouples, otherwise you
