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 | 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
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 | Thu Feb 23 13:56:21 EST 2006 | slthomas
I have dealt with it before and usually it's consistent, so you use some simple math to work around the issues. Now, if you have so much variability between different locations on your board for resist thickness, HASL thickness, etc., that it fouls
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 | 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 | Tue Jan 07 23:38:08 EST 2014 | m_imtiaz
want to know the tolerance the paste height in the solder paste printing. for example if stencil thickness is 7 mil, what will the acceptance level of paste height ( upper and lower) kindly share if any guidelines or formula for the same
Electronics Forum | Fri Jan 24 08:14:24 EST 2014 | davem
m_imtiaz, Over the last 15 years or so I've found that using the stencil foil thickness +2mils/-0mils has worked very well. For example, if you have a 5mil stencil thickness your upper control limit would be 7mils and your lower control limit would
