Electronics Forum | Mon Mar 20 22:39:03 EST 2006 | davef
Pavel Point: You suspect that solder paste can easily get to solder mask causing beading, because the aperture is larger than the component pad. Comment: Probably, this is incorrect. We overprint on solder mask all day long when doing paste-in-hol
Electronics Forum | Tue Mar 21 08:22:11 EST 2006 | jdengler
If you usually get good release on other products with your paste, I would try a different batch of paste. The batch you are using may have a problem that contributes to the beading. Jerry
Electronics Forum | Tue Mar 21 18:52:45 EST 2006 | GS
Ahoj Pavele, di you considered to try a Type-3 solder paste ? Best Regards...........GS
Electronics Forum | Tue Mar 21 02:15:26 EST 2006 | pavel_murtishev
Good morning Dave, Here are some of my assumptions. Please correct me if I am wrong. 1. Mask opening. Due to mask to PCB misregistration mask is not always centered relative to pad center how is should be. Sometimes edge of the mask matches with ed
Electronics Forum | Tue Mar 21 21:03:55 EST 2006 | davef
1 Chatter about mask opening � No BIG problems with these statements. It�s just that you may need to tailor your reflow recipe to minimize these escapees. 2 Stencil design - Any area ratio below 0.66 is going to very challenging to print, as you ca
Electronics Forum | Sat Mar 18 02:21:31 EST 2006 | pavel_murtishev
Good morning, Once again a met annoying solder beading issue while producing board with PLL (leadless, contacts from the bottom side of the package). Board has very high placement density and beads appear near PLL package only. This package is finep
Electronics Forum | Mon Mar 20 00:48:22 EST 2006 | pavel_murtishev
Good morning, In this case separation speed doesn�t affect print quality. Separation speed decrease makes print quality the same or worse. Apertures still remain blocked. Any ideas? Thanks. BR, Pavel
Electronics Forum | Thu Mar 23 06:38:30 EST 2006 | pavel_murtishev
Good afternoon, We can use type-3 solder paste, but what for? Type-3 solder particles are larger than type-4. Probably this will cause even worse release. BR, Pavel
Electronics Forum | Sun Mar 19 16:32:05 EST 2006 | ausajid
hi same sort of broblem v r getting after reflow. i am not sure about the solderbeads how u can reduce, but the other issue u r talking about is apeture blocking.... u can reduce it by reducing the seperation spead. reduce it as low as 1-2mm/sec. th
Electronics Forum | Thu Mar 23 10:02:09 EST 2006 | Joe
Check placement pressure. I agree with the "smushing" theory. If you can place the component with less pressure, I'd do that first. A switch to Type three paste is also a good idea, as long as your minimum aperture dimension remains at 0.009" as you
winsouce.jpg)
