Electronics Forum | Fri Jun 24 07:02:35 EDT 2005 | davef
Problem 1: Solder shortage * Stencil aperatures [except the heat slug] should be 1:1 with the board. * Stencil should be 5 thou thick laser cut. * Board should be 1:1 with the component * Print should look good. Problem #2: Bad connection between p
Electronics Forum | Wed Mar 27 16:54:47 EST 2002 | davef
STARTING RANGES * Pressure � 1 pound/inch of blade (metal); 1.6-3 pound/inch (plastic) * Speed - 0.5 to 3 inch per sec [for standard pitch]; 0.5 to 1 inch per sec [for fine pitch] Your paste supplier�s recommendation is a good place to start. * Sepa
Electronics Forum | Tue Mar 18 14:00:25 EDT 2008 | rrpowers
There are 2 reasons for wanting to change to an enclosed print system: - Reduce solder paste usage. (We run a high volume application so any reduction in paste scrap is a big money saver to our company.) - Improved print quality. (Ours is a non-rew
Electronics Forum | Fri Sep 22 14:10:19 EDT 2017 | slthomas
Just for the sake of passing along the information, the fine grained stencil provided zero improvement over the standard PhD stainless and was not nearly as helpful as the baked-on nano-coating. We probably won't be trying that again unless we go und
Electronics Forum | Wed Sep 06 18:19:37 EDT 2017 | slthomas
Hi All, We are being intermittently challenged by a .5mm pitch uBGA paste release issue. We don't build with many of these so don't have a lot of history here. We've gone through 3 different stencil designs and the most consistent performer was 4 m
Electronics Forum | Wed May 05 06:30:40 EDT 2021 | jineshjpr
Do Proper underneath stencil cleaning. if the cleaning not effective, check Vaccuum section of the printer machine. Else change the Wipe roll. Trying out with other cleaning solvent (dedicated to stencil cleaner) also improve this issues.
Electronics Forum | Wed Jun 04 07:56:36 EDT 2008 | ck_the_flip
Does anybody use a paste mixer in their shop? I am looking at one that uses "Psuedo-Planetary Motion" to mix and soften solder paste. If someone answers "yes", has this benefitted your paste consistency and improved your print repeatability?
Electronics Forum | Thu Aug 12 14:17:19 EDT 2010 | mikesewell
You might reduce your panel size, cut it in half and rotate to better utilize your edge clamping/board supports. Tape off your current stencil and see if it improves the print. A new stencil and a little extra handling may be cheaper than tooling.
Electronics Forum | Wed Nov 02 04:28:58 EST 2005 | Simon
Hi James, I have worked in many SMT sites and this is not an uncommon practice. It is true that print deposit consistency will improve after the first few prints as the aperture walls become lubricated, but with modern stencils/paste and a well-desig
Electronics Forum | Wed Feb 03 15:42:31 EST 2016 | tombstonesmt
The way I view SPI is that is simply a tool. A tool to gather data to improve printing and prevent failures down the line due to screen printer anomalies. They can all inspect paste as necessary, work in closed loop with screen printer and provide a