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 | Sat Jul 01 04:22:09 EDT 2000 | Sal
I have two questions 1. How do I control the skewing of FETs/power regulators ? ( the one's with the big rectangular pad and two smaller one's for the leads).If I go 1:1 with the apertures I seem to get solder balling and when I tryed to minimise th
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 | Sun Oct 10 17:57:48 EDT 1999 | JohnW
Folk's, I'm just tying up some loose end's on my Master's Thesis on solderballing @ wave soldering and the effect the topography of the mask / PCB has on it. I was wanting to do a straw poll on you guy's as to the type of resist's you are using Glos
Electronics Forum | Mon Oct 11 13:08:29 EDT 1999 | Dave F
| Folk's, | | I'm just tying up some loose end's on my Master's Thesis on solderballing @ wave soldering and the effect the topography of the mask / PCB has on it. | I was wanting to do a straw poll on you guy's as to the type of resist's you are us
Electronics Forum | Tue Sep 21 04:00:27 EDT 1999 | Wolfgang Busko
| My stencil thickness is 6 mil and we got qfp's with fine pitch. | how many percent should i reduce my stencil aperture using a 6 mil stencil for 0.5 mm pitch and 0.4 mm pitch ? | | thanks | We use 6 mil lasercut stencils with 15% reduction and th
