Electronics Forum | Mon May 24 13:11:12 EDT 2010 | deanm
A guideline that I use agrees with MikeS: For 20mil pitch, apertures should be 9-10mil with a stencil thickness of 5-6mils to achieve an acceptable aspect ratio of 1.7. Just be sure you are using a mesh Type 3 or 4 solder paste. Otherwise, larger par
Electronics Forum | Tue Feb 15 14:35:41 EST 2000 | Balas
hi I am designing a test vehicle with a range of components on it(pbga, cbga,fc, mbga, and qfps). My concern is that I would like to use a single stencil for solder deposition and not a stepped stencil. That would require me to have aperture design a
Electronics Forum | Tue Oct 31 20:42:56 EST 2000 | speedy-tech
Now we are face with tombstoning for component '0402',we have tried many ways,it seems no change,Below is our experient: 1,The thickness of stencil is 0.12mm,and the aperture is circle.the diameter is 0.55mm.The pads size is 0.5*0.6. 2 Ch
Electronics Forum | Tue Feb 22 10:44:12 EST 2005 | Dougs
when you talk about stencil design, what would you recommend for aperture size on fine pitch if the customer insists on hasl finish on fine pitch devices? i usually use a 10% reduction on everything we have been using ( 16mil pitch and upwards and 0
Electronics Forum | Sat Aug 05 12:12:05 EDT 2000 | Ramon I Garcia C
Hello Friends: I'm new in SMT process, I have a problem with little balls of solder beside of the component, I'm tried reducing the apertures in the stencil and making home base, some times the balls desappear, but some time not, and some times
Electronics Forum | Tue Dec 21 19:57:45 EST 1999 | Russ
All of the information so far has been great, I would like to add one more thing to the puzzle. We have utilized a "homeplate" aperture on the stencil when the pad geometry or PCB design prohibits all of the above mentioned remedies. The hompeplat
Electronics Forum | Fri Apr 29 07:14:13 EDT 2005 | jdumont
Recently we have been seeing issues with an inability to print through .45mil apertures on our stencils. We have also been seeing a alot of solder balls under some BGAs (some worse than others). I was checking the refridgerator (small mini fridge) we
Electronics Forum | Thu May 18 11:00:51 EDT 2006 | Chunks
Thanks Doctor - as always, you're right. I must've been typing with my mittens on. It's starting to get cold on this part of the planet these days. I wasn't blaming anyone, just trying to take a few questions marks away so "we're" left with the an
Electronics Forum | Mon Oct 09 10:00:15 EDT 2006 | C.K. the Flip
I had a customer like this too. Originally, the customer print called for manual soldering of the RF shield (which took us about 20 min. per shield to hand solder), but I changed it to Solder Reflow (I cut apertures on the stencil), with brass weigh
Electronics Forum | Mon Apr 13 17:03:40 EDT 1998 | EFData
We are having some difficulty soldering a 240 pin Altera device. We use Alpha WS-609, a very generic profile for that solder paste, and a 6 mil stencil with laser cut apertures (1:1 ratio). This is a 20 mil pitch device (aperture size is 10 mils X 75
