Electronics Forum | Wed Jun 08 13:49:48 EDT 2011 | sonofptolemy
Hello, I am having a problem with HASL PCB's after it comes back from the stuffer. To me it looks like oxidation and it causes poor wetting. This leads to a bunch of problems all of which have different symptoms but the cause is this oxidation proble
Electronics Forum | Tue Oct 04 04:47:04 EDT 2011 | grahamcooper22
Having a selective solder machine without a preheat sounds ODD. Preheats are pretty important to drive off flux volatiles and activate the flux so it cleans the parts ready for the solder to wet to them. If you have no preheat then you must be expec
Electronics Forum | Thu Oct 27 16:49:05 EDT 2011 | CPI
I’m looking for information regarding Reach and what a contract manufacture is required to supply their end customer. We are just getting our feet wet with this requirement and I want to make sure we nail this out of the gate. Is it just the MSDS tha
Electronics Forum | Mon Apr 09 19:50:33 EDT 2012 | action_101
Hello, We're building some boards with 01005's and the only issue we are running into is the solder is not reflowing. It's the damnest thing, we are having no issues with the printing process or placing the components, the two areas we thought we wo
Electronics Forum | Thu Aug 30 20:35:51 EDT 2012 | davef
A common bottomside heater configuration is IR-Convection-Convection. One of the big advantages of the IR zone is its ability to allow the flux carrier to spread and dry slowly before the board reaches the convections zones, which can blow wet flux c
Electronics Forum | Wed Feb 20 10:12:27 EST 2013 | dontfeedphils
Hey Bill, it really depends on the material you're looking at using UR, SR, AR, the easiest to deal with being AR, although if you can find a UR that doesn't clog up the machine too bad those are usually more viscous and easier to apply selectively u
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 | Fri May 31 18:00:55 EDT 2013 | hegemon
With regards to first picture.(Large themal vias) I would attempt to measure the area of the ground pad, less the area of the "drain" holes or Thermal Vias. From that result I would reduce the aperture to account for about 50% coverage of that remai
Electronics Forum | Thu Feb 13 19:08:31 EST 2014 | darby
Have to agree with Sr Tech and Spoilt - you'd have to really mistreat your paste these days for it to be the root cause. However, try another paste to eliminate that; making sure you abide by the suppliers specs. Pad design, stencil design,(includin
Electronics Forum | Thu Apr 03 17:50:53 EDT 2014 | rboguski
We use it almost exclusively in manual mode for PCBA failure analysis. Our main purpose is to find head-in-pillow defects; secondarily incomplete wetting of ball to substrate. In two years of almost continuous use we have only had occasion to use t
