Electronics Forum | Thu Feb 28 18:23:39 EST 2002 | davef
No, not as such. Nor should there be. This is not to say that the issue of making good prints is anything but absolutely vital to cost effective operations. Experts attribute 60+% of SMT soldering defects to the printing process. Properly, both J
Electronics Forum | Wed Mar 06 21:24:09 EST 2002 | davef
How could you know if your printing process is capable or in control if you don't have a print measurement tool? You�re correct that you do need a measurement tool to determine if the process is capable or in control. A $1.5k microscope and some g
Electronics Forum | Mon May 09 16:44:33 EDT 2011 | dcell_1t
Hi, We have been struggling with an issue of non wetting on a QFP (Renesas - 256, Sn90Pb10) but the issue "desapears" sometimes for a while and then back again suddenly. This is the scenario: Component: QFP 256 / Renesas / Sn90Pb10 / 0.5 mm pitch S
Electronics Forum | Thu Apr 14 13:24:18 EDT 2016 | davef
I doubt that your problem is driven primarily by irregularities in your circuit board. My bet is that you’re seeing defects caused primarily by the warpage in your LGA. Consider using advice often given for minimizing warpage caused defects in BGA
Electronics Forum | Tue Sep 06 09:20:50 EDT 2005 | Bob R.
We approached it the same way we select SnPb pastes. We started by doing coupon level tests to sort out the obvious "bad" pastes: SIR, wetting, solder balling, print quality, etc. That cut the field in half. From there we started to do assembly l
Electronics Forum | Wed Apr 03 19:03:31 EDT 2013 | hegemon
In agreement, in that you should have already printed enough paste on the board to accomodate the joint. Adding paste would give the result you described. (too much solder) Adding a little flux (only) and heat would be the correct path out of that s
Electronics Forum | Wed Mar 27 19:26:53 EST 2002 | ianchan
After a whole night's self review, I think we can term the slant/tilt as "floating 0805, yet end-terminals have acceptable solder joint formation". the width portion of the 0805 RES/CAP is (floating)elevated from the PCB pad, yet both (width) termin
Electronics Forum | Wed May 12 08:16:33 EDT 2004 | solderpro
woow, slow down hot rod, hey davef, you are alright by me, good to see some one out there that has hands on experience rather than a theory nut.... any how, you need a top of the line profiler, super gold mole, or Kic.... these truly are the best and
Electronics Forum | Tue Oct 06 08:20:13 EDT 1998 | Charles Stringer
| Does sombbody know what DPM rate a good and reliable SMT assembly line (incl. solder paste print, assembly and feflow soldering) has? | DPM is Defects per million, usually measured on components. We run a process consisting of small to medium batch
Electronics Forum | Wed Jun 12 11:14:57 EDT 2002 | pjc
Sam, Like I said, AOI for pre-reflow inspections is the easiest to program and maintain. Each vendor of AOI has its pluses and minuses for programming and performance. Do a careful investigation of each vendor to learn about their machine performanc
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