Electronics Forum | Tue Feb 21 21:17:41 EST 2006 | Cal Kolokoy
M, The paste height is what you establish it as. You're probably using a laser measurement system, and these depend on where your reference datum is. Some will measure from a silkscreen, a trace, or solder mask. These add height, not to mention H
Electronics Forum | Tue Jun 07 10:38:34 EDT 2011 | davef
Boots: Here's several methods for guessing at the amount of solder on your connection: * First, 'Down & Dirty' ** Assume that the solder is flat, which is reasonable since it's 'flattened' by the component package ** Assume 100% paste transfer from t
Electronics Forum | Sun Sep 27 22:39:55 EDT 2009 | rajeshwara
The same issue i faced 2 yrs before , i sugest 1. Use stencil of 4 mils ( Take care of Aspect Ratio and Area Ratio ). 2. Use Solder Paste of Type 4.5 and Viscosity in between 1100 to 1300. ( Try Solder Paste of Cookson or Alpha metals : OM338 T45-L
Electronics Forum | Mon Jan 23 22:53:31 EST 2012 | davef
= 0.66 aperture opening to the stencil wall has been shown to provide the best transfer efficiency and repeatability of the deposited paste. Values from 0.66 to 0.8 insure a good paste release from the stencil. The biggest impact on area ratio is the
Electronics Forum | Mon Mar 24 20:30:01 EDT 2014 | davef
The "correct" answer is: Use the tests and methods that you used to qualify your solder paste in the first place. That sounds good but might not be all that practical for practicing assembly-types. Here's something that's not as good, but will give
Electronics Forum | Wed Jul 06 09:07:28 EDT 2016 | davef
Hi Pavel IPC-6012 - Qualification and Performance Specification for Rigid Printed Boards, Paragraph: Solder Resist (Solder Mask) Requirements, Sub-paragraph: Solder Resist Thickness has words to the effect … * Solder mask thickness shall be accordi
Electronics Forum | Mon May 20 16:15:48 EDT 2019 | davef
Resources are: * IPC-7525A - Stencil Design Guidelines, 3.5.2 Step-Up Stencil This type stencil is useful when it is desirable to print thicker solder paste in a small portion of the stencil. An example would be a ceramic BGA where it is necessary t
Electronics Forum | Sat Jan 04 09:02:17 EST 2003 | davef
Q1. What is the recommended stencil thickness to apply the proper amount of solder for 0603 components? A1. The proper amount of solder is determined by: * Metal content of the solder paste. * Stencil thickness. * Aperture opening. * Other factors,
Electronics Forum | Thu May 21 09:54:07 EDT 1998 | Justin Medernach
| I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and solde
Electronics Forum | Thu Feb 23 09:59:09 EST 2006 | SIR
We have an AUREL CS1222 machine to measure the thickness of the solder paste deposited on a bare board by a stencil printer. This device has a laser beam that has to be put on the pad where you want to measure the solder paste thickness. The measure
