Electronics Forum | Thu Feb 24 11:05:53 EST 2000 | Russ
I usuallly like to have the pad size the same size as the ball up to +2mil, the pcb solder mask opening to be +4 mil from the pad size (I have found this to aid in Xray inspection for opens since you can see the little tail of the solder wicking up t
Electronics Forum | Tue Aug 27 08:12:35 EDT 2002 | jmaruska
Do you have some experience with solder paste WS1208. What is the "best" conditions for printing process? I mean type of stencil, apertures, squeegee. Do you have original data sheet of this solder paste? - life time, working time on the stencil, sh
Electronics Forum | Fri Nov 30 23:28:54 EST 2007 | mika
BTW, Option 6. Bear in mind though, In the stencil printer if you run into a problem like this, it will not work with the holes...Only what's in the stencil... We have under some rare circumstances used 1-2 pad's on opposite corners and on very large
Electronics Forum | Wed Dec 10 07:47:16 EST 2008 | benefon
If you find the correct type of adhesive/needle size then dispensing certainly is no problem. With a footed needle a very repeatable process too. Much more flexible than stencil printing and no need to mess around with stencil cleaning. But with auge
Electronics Forum | Wed Aug 29 03:16:20 EDT 2018 | cannizzaro
It is recommended that the thickness of the stencil of 0.1mm, the steel mesh should be partially nano-coated. It is best not to dry easily, and the particles are not easy to be too large. I have tried ALLPCB for this kind of BGA in the past and they
Electronics Forum | Thu Aug 24 19:26:07 EDT 2006 | darby
Dave, Cygnal was taken over by Silabs. I based my design on the second link that you provided. Tell me folks, are you using one large pad with only the stencil having the grid, or are you actually breaking up the large pad into grids with mask around
Electronics Forum | Tue May 02 05:59:28 EDT 2006 | davef
We agree with Ken's points about off contact / screen versus stencil, but this DHolt is talking stencil [regardless of what is typed about screens]. Comments are: * On "smears under the stencil": smearing happens. It makes us wonder about the frequ
Electronics Forum | Fri Sep 06 00:29:24 EDT 2002 | TLe
Peter, QC-calc: Verifying vision accuracy of your printer with calibration stencil and hundreds of repeats. If your boards are large and specially if you have finepitch parts on them you will find usefully to use QC-calc to measure board stretch/sh
Electronics Forum | Fri Dec 27 14:11:18 EST 2002 | cnotebaert
We have placed these parts. I have not had problems with them but when I designed the stencil we reduced the app for the large thermal by 20% to reduce the chance of problems like your having. If the balls are close (.040-.050" or
Electronics Forum | Fri Sep 17 09:44:26 EDT 2004 | davef
We agree with Russ. * Haven't used them in 10+ years. * Size of keepout for the stepped apertures needs to be large. * Manipulating aperure size to manage paste volume for specific components is not difficult.
