Electronics Forum | Mon Aug 14 15:09:14 EDT 2017 | charliedci
In my experience, in a temperature/humidity controlled environment, 1 hour, no big deal. 4 hours still ok. Overnight your pushing the limits but will probably reflow without issues. Any longer, could be a problem. Again, a lot depend on type of past
Electronics Forum | Wed Nov 20 09:23:53 EST 2019 | alpha1
We had a board we fought with for a while with solder balls. Checked everything, Stencil thickness at .004, reduced apertures, changed paste 3 times, changed profile 3 times. Finally changed board vendors. Went from HASL to Emersion Gold. Problem sol
Electronics Forum | Wed Jul 06 15:29:01 EDT 2022 | glasscake
Also I should mention, I've ditched the formulas for getting the "optimal" solder amount after being bit by them once. Now I just design a PCB with 4-10 spots for the connector then order a stencil with a range of aperture sizes. Figure out what give
Electronics Forum | Mon Aug 14 14:27:00 EDT 2017 | emeto
Here is some food for thought. Try to answer these questions yourself and I am sure you will see huge improvement. Reasons: - Bad PCB design - Plating-uneven HASL cause more than OSP Au/Ni or Silver - Poor paste and print quality - uneven paste ca
Electronics Forum | Thu Nov 22 10:02:42 EST 2001 | Adam
Guys Has anybody had experiences with plastic glue stencils good or bad ? I also have a couple of questions : 1. Can I use the same aperture design rules for plastic stencils as I do on my metal glue stencils ? 2. How repeatable is a plastic glue st
Electronics Forum | Fri Mar 04 15:22:17 EST 2005 | russ
Glad to hear a little success from ya Duckmann! i have stenciled mask in the past and I can tell you that stencils are expensive. They are basically a step stencil, you will need full thickness for the area(s) you are going to apply mask and you wi
Electronics Forum | Thu Nov 12 13:16:52 EST 1998 | Ryan Jennens
| I keep hearing about polyimide stencils, but what are they like in terms of registration and aperture accuracy? | Fraser- We use polyimide stencils with great success for our prototype boards. They are cheaper and the accuracy/aperatures are
Electronics Forum | Fri Oct 28 09:27:36 EDT 2005 | russ
havfe you tried all paste manufacturers? Dog ears are usually from a little sticking to the aperture walls. this is usually the result of stencil design and or table seperation speed.
Electronics Forum | Wed Feb 14 11:00:55 EST 2007 | CK the Flip
Rob, just curious how did you overcome this through stencil design? Did you play around with foil thickness and aperture geometry?
Electronics Forum | Thu Sep 13 01:37:15 EDT 2007 | pavel_murtishev
Good morning, Overprint, i.e. make stencil openings for your LED larger. Add printer accuracy to aperture size so that paste would always cover the pad. BR, Pavel
