Electronics Forum | Thu Mar 08 18:39:06 EST 2007 | elias67
Stencil Thickness should be .005" A reduction along with cross hatching is a must for the center pad to reduce paste volume as well as to assure even paste deposit while printing on a large pad. With out the cross hatch, the squeegie will most like
Electronics Forum | Thu Sep 02 12:40:55 EDT 1999 | John Thorup
| Dear Netters, | | Can you kindly suggest what cause solder splash in IR reflow boards ?? What are the main causes normally ?? | | | Best Rgds, | Felix | Felix - we need a better description of what it looks like. If it's a spray, usually balls
Electronics Forum | Sat Mar 29 01:59:09 EST 2003 | iman
Yep, only the MLF have this blowhole/pinhole issue. Other components like SOT(transistor), CAP, RES are hey-o-kie. Btw, MLF = micro lead frame (IC/LGA) package. looks like a BGA without the solder balls. has direct attachment to the PCB ENIG pads wi
Electronics Forum | Thu Oct 31 16:13:46 EST 2002 | babe
If your processing with Nitrogen, tombstoning can be caused by your cooling rate. Go thru the solid/liquid phase of the solder slower..iN other words as you transition into or out of the liquidus pahse if 63/37 alloy 183C, ensure that your Delta are
Electronics Forum | Tue Dec 11 13:56:38 EST 2001 | Damian Holzmann
Regarding your comment "technology doesn't seem to have improved". Actually, technology has improved significanty. Cyber Optics uses a line measurement, a new unit from Germany uses sine wave differential measurement. The Gridmeter unit captures a vi
Electronics Forum | Thu Feb 18 08:35:10 EST 1999 | Dave F
| We have problems with solder balls after reflow. Anybody have any ideas as to what causes them? | Al: Tuffty's comments are good, but point to the broader problem in trying to make recommendations on your problem ... There's just not enough info
Electronics Forum | Fri Jan 19 10:18:44 EST 2007 | Simon C
Hi, We have at DEK printed paste through a Pumprint stencil onto clinched leads, but there will be limitations depending on the product. If you can send a sample loaded board to me indicating where you want paste deposits then I can certainly take a
Electronics Forum | Fri Sep 16 19:46:55 EDT 2011 | jlawson
I have seen this on Heller1707 machines also for LED devices. The same job was run on anthoer brand oven (Rehm) and no issue. I think Heller Blower velocity can be a little on higher side as is a low inertia heating system and they have to make up f
Electronics Forum | Mon Oct 09 15:03:08 EDT 2017 | emeto
From what I know from people using it - it is a great machine. Allows you to have unique shape and amount of paste for every single pad. Great for small volumes, prototyping series and a great replacement for step stencils and any other occasions, wh
Electronics Forum | Fri Apr 20 03:04:24 EDT 2018 | tsvetan
We usually replace stencil when we start to get problems with the solder paste printing i.e. uneven solder paste deposit etc. Until then it doesn't matter how many years ago it's manufactured, but how many prints it passes and if the operators didn't
