Electronics Forum | Tue Jul 03 08:14:49 EDT 2001 | Stefan Witte
If you hold your board sideways in a 90 degree angle you apply a force of 1 g to your components. 1 g translates into 32 ft / sec. square. This is not too much acceleration for fearless roller coaster drivers but Melf�s and Tantalums can fall off at
Electronics Forum | Mon Nov 18 09:04:20 EST 2019 | davef
Review: * Too much placement force * Underside supports are set incorrectly * Component height set incorrectly * Downstroke location of either the pick or placement set incorrectly * Nozzle that is smaller than recommended for the part * Part
Electronics Forum | Thu Mar 15 13:39:06 EDT 2018 | gregp
Impact is the instantaneous force at the time the component first reaches the PCB. F=M*a....so the acceleration is the key factor. If charted on a graph it would look like a spike...higher force for a short duration. The placement force is typical
Electronics Forum | Sat Feb 05 13:25:32 EST 2005 | etienne
Just a basic suggestion.... Inspect the nozzle placing the component...because that is the only medium, apart from the PCB design, which can be causing the damage. It occurred in my Department.
Electronics Forum | Thu Oct 21 04:21:55 EDT 2004 | siverts
Have been through this before and we resolved our problem as follows: 1.Make sure that the length of your board support pins on Your HSP is correct. On that machine the board support pins depends on the board thickness (+ - some tenth's of a mm). It'
Electronics Forum | Tue Sep 08 15:11:26 EDT 1998 | Mike Demos
Rich: In my experience, I have seen three cases of SMT Capacitors cracking: 1. Due to thermal shock when entering the wave solder. Note that these were 1210 package sizes on the wave solder side of the boards. We were able to trace this back to th
Electronics Forum | Wed Dec 04 21:39:53 EST 2002 | davef
As you say, some BIG time force has pulled the metalization from the bottom of the component termination. From the pix it's hard to say whether it was caused by either: * Mechanical flexure of the board during an unusual heating or other processing
Electronics Forum | Thu Oct 02 17:55:16 EDT 2008 | davef
~le sigh~ makes a good point about forcing bent leads into the solder, letting the solder cool, and releasing the force on the lead. On the other hand, reforming leads of components prior to assembly is dangerous, also, because the "bending of a lead
Electronics Forum | Mon Nov 09 11:56:59 EST 1998 | Stefan W.
At least I can imagine what happens and it may solve your problem. If the vacuum is already turned on above the component there will be an airstream above and around the component. This might even suck the air out of the cavity, which supports the co
Electronics Forum | Tue Jun 16 09:15:56 EDT 1998 | Justin Medernach
| We are very concerned about microcracking in SMT P&P process. I want to know something about: | What is microcracking? | When did it occur? What are the causes? | How can avuid this phenomena? Toni, Micro cracks can be caused by a ton of conditions
