Electronics Forum | Thu Jul 21 09:43:10 EDT 2005 | davef
We agree with Russ. The solderballs are probably the result of printing too much paste on the board. In designing your 5 thou thick stencil: * Aperatures for the pads should be identical to a IPC-7351 - SO8 [or worst case http://www.vishay.com/docs
Electronics Forum | Tue Sep 26 08:42:49 EDT 2006 | aj
me and my big mouth. we are currently running a leadfree product and I am getting MCSB on all 1210 caps. Using homeplate with 10% reduction 6thou stencil. I contacted my stencil supplier to ask for advice- they are looking into it but he did menti
Electronics Forum | Tue Sep 26 12:01:30 EDT 2006 | sliebl
We have solved our MCSB problems by using standard homeplate designs on all of our resistors and caps. I use a 50% taper and have achieved great results with 0402-1206 parts using both tin/lead and SAC305 paste. We use Amtech paste.
Electronics Forum | Mon Oct 30 09:24:21 EST 2006 | ronalds
I have some problems in sufficient preheating the pcb's. They splatter on the mainwave, causing solderballing. Less flux causes problems with the fill of the through- holes. We use a Delta Wave with 3 preheat zones, the first two are calrods the thi
Electronics Forum | Tue Apr 24 02:56:12 EDT 2007 | chrispy1963
If the PCB you are using is a HASL pad finish and is a leaded assembly, we use homeplate pads with a 5 mil stencil. If the circuit has Enig finish and is PB-Free then we use 1:1 apertures with a 5 mil stencil Either method should provide no solde
Electronics Forum | Tue Jan 15 08:50:07 EST 2008 | ck_the_flip
Based on past, actual, hands-on experience, I have found that the PCB mask finish makes a HUGE difference in solder-balling. Glossy has different surface tension and peelback characteristics than matte finish (ie glossy sucks). http://circuitsassem
Electronics Forum | Mon Jan 19 05:02:07 EST 2015 | gertjannus
I've some troubles with LGAs components. i try to create void free results. so far i have no problems with dpacks, i think i do something wrong with the vacuum time. The padcoverage of my lga is very bad the vacuum creates solderballs under the compo
Electronics Forum | Thu Jan 02 07:04:57 EST 2020 | dontfeedphils
Pretty large solder-ball. Looks like it may have come from the ground pad since it's so large, in which case I would reduce the print coverage on the middle/ground pad and see how it works for you. You verified that these parts have the groundpad a
Electronics Forum | Fri Mar 03 09:48:06 EST 2000 | Wolfgang Busko
I have heard about it. The main reason is to save money. The problem is, or better is said, that the mixing isn�t that simple for you got have a homogen paste afterwards and the solderballs shouldn�t be deformed in size so that problems during printi
Electronics Forum | Tue Aug 22 14:52:55 EDT 2000 | John Thorup
Jax - absolutely right - the archives are a valuable tool and deserve to be used more than they seem to be. Caumel - Are your blobs on the solder side or the component side? Are your vias tented on the component side? What size are your vias? Is th
