Electronics Forum | Tue Feb 22 01:38:42 EST 2005 | JSS
We r using QFPs of 0.5mm pitch and r not getting any soldering prob at the end.But some new customer insists upon the thickness check of the solder paste after printing. At present we don't hv thickness checking system.We r controlling the amount of
Electronics Forum | Thu Mar 17 13:03:21 EST 2005 | Slow Ride
When it comes to solder paste, you should worry about volume. Granted height is a part of the equation, but you could have perfect height and still get defects. I wouldn't get too wrapped up in volume either, unless you're evaluating stencil height
Electronics Forum | Mon Mar 02 11:13:59 EST 2009 | jorge_quijano
Hi to everyone, I'm new with the Solder Paste Inspection machines, and I'm doing my first measures and I noticed that I'm getting a solder paste heigth of 7 & 8 mils using a 5.0 mils stencil, with metal squeegees and 0.0 Snap off. are this results no
Electronics Forum | Wed Jan 08 08:20:52 EST 2014 | emeto
To most of our boards I give 20-30% tolerance in both directions. From experience if you have big aperture on your stencil, the squeegee will scoop certain amount of paste from this aperture and you will see lower height. Depending on your board supp
Electronics Forum | Mon Feb 21 02:02:54 EST 2005 | JSS
First of all THANKS for thr reply. I totally agree with u that paste dried,stencil aperture clogged like probs comes during the production but we hv a visual inspection stage (with 5X illuminated lamp)after printing process and before inserting the
Electronics Forum | Fri Apr 20 08:41:56 EDT 2001 | jimlew
For those of you out there, like myself who are still using 2-d to measure paste ht, I have 2 questions. 1. Typically, what tolerance are you applying to your ht? +- 1 mil, or what? 2. Are you using metal squeegees, and if so, have you found that squ
Electronics Forum | Fri Apr 20 16:05:17 EDT 2001 | gcs
We always reduce side to side, EXAMPLE: 12 mil width reduced to .010". Do you guys check viscosity ? Also maybe your guys are appling to much pressure on the sqweegee blades.
Electronics Forum | Fri Apr 20 11:05:23 EDT 2001 | gcs
Just a bullet! My results are, .005" stencil thickness should measure between .0055" - .006" if your pressure is correct, metal blades and snap-off is set up correctly. Do you have aperture reductions at the QFP locations "typicial industry standard
Electronics Forum | Fri Apr 20 15:27:00 EDT 2001 | jimlew
We do some aperture reductions - but it's not the 10% i'm accustomed to. Looks like it should be more than we currently do (I think we do 10% of length, but no width). Don't think we have a slumping problem, and we're not doing snap-off, only contact
Electronics Forum | Thu Sep 08 01:58:08 EDT 2005 | darby
0. Any less and you are scooping the paste from the aperture with the squeegee blades. I'm not saying that either of these situations is a good or a bad thing, it's just that if you buy a 6 mil stencil, you are trying to achieve 6 mil paste height.
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