Electronics Forum | Fri Apr 02 22:01:19 EST 1999 | Dean
| Anyone knows what is the optimum squeegee angle for screen printers. | | 45 Degrees. The forward velocity creates a downward pressure equal to the vector pressure (equalibrium). This is commonly known as paste "rolling action". Too obtuse an an
Electronics Forum | Wed Jul 27 09:58:05 EDT 2011 | davef
Pressure printing systems Conventional stencil printing techniques have fundamental limitations as regards paste handling: The volume of paste available for printing is limited, so frequent replenishment is necessary Paste is difficult to c
Electronics Forum | Thu Mar 22 17:38:44 EST 2001 | davef
OK, lemme take a different angle on this, �cuz I forgot to touch on this when I first responded. I mentioned a study ["Evaluation of Low Residue Soldering for Military and Commercial Applications: A Report from the Low-Residue Soldering Task Force"
Electronics Forum | Mon Feb 10 16:59:57 EST 2014 | hegemon
It is sort of a self answering question if you come in from the solder paste angle. First....start gathering data. Check every day, or every new paste jar, for: Storage conditions (temp), paste expiration date, ambient temp and humidity where yo
Electronics Forum | Thu May 26 08:52:42 EDT 2011 | davef
Phil Zarrow wrote a useful paper that could help in evaluating paste. Here read it ... Evaluating Solder Paste � Not An Option Contributed by Phil Zarrow of ITM an Independent SMT consulting firm With soldering being the dominant source of assembly
Electronics Forum | Thu Jun 02 07:27:11 EDT 2011 | scottp
You need to post a picture or describe your geometry better. Is this a through hole via in pad or is the via offset from the pad with no soldermask in between?
Electronics Forum | Thu Oct 02 12:22:26 EDT 2008 | JerryS
Hello Ok there is not much info here. What you have to mae sure of is several key factors. 1. Have you entered the correct stencil thickness. 2. Are you using the stencil gerber (not the paste layer) The paste layer is usually not adjusted for ap
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 | Thu Apr 23 21:07:09 EDT 2009 | luismolinero
Emilio: Several factors you need to take into account and your process parameters will depend on: Solder Alloy, Is there any Fine Pitch?; BGA?; Smaller chip size?. Tipically you should go for controls in: Solder Temperature and viscosity; blade and s
Electronics Forum | Wed Mar 04 15:26:07 EST 2009 | clampron
Hi Jorge, Take a bare board and measure over the same pad. We have had similar issues with a higher deposition than the stencil thickness. In some cases, we have found that the top of the pad was higher than the solder mask. Our inspector uses the b
