Electronics Forum | Tue Apr 26 15:21:11 EDT 2005 | russ
Sounds to me like they are thinking since they have a gold board that it must be processed lead free. This kind of thing is happening all over since OEMs are starting to think about pb free and sending their purchasing and engineering to these semin
Electronics Forum | Sun Jul 29 08:36:39 EDT 2001 | davef
You have provided very little information. Two similar possibilites come to mind: poor pad solderability protection and old boards. POOR SOLDERABILITY PROTECTION: Maybe the nickel plating under the gold is oxidized, contaminated, or otherwise very
Electronics Forum | Tue Jul 31 13:46:17 EDT 2001 | Hussman
How fast is your print head speed? I've found that I had to decrease my print head speed to get the paste to stick to gold pads. Not exactly sure why - but the ol' instincts worked well.
Electronics Forum | Sat Jul 28 03:05:35 EDT 2001 | Frank
Hi guy Does anyone have experiance with printing problem between solder paste water soluble 62/36/2 and gold plating PCB? I do have problem about insufficient solder after printing although I used the same printing parameter as when I print with ano
Electronics Forum | Sun Jul 29 23:58:08 EDT 2001 | Frank
Hi Dave Thanks for your information. The problem that I found is paste not stick well on pads ( solder paste printing process). When the table move down (PCB saperate from stencil) some of paste stick on aperture instead pads. Solder paste : Delta
Electronics Forum | Wed Aug 01 06:52:25 EDT 2001 | Mark
please look at trying lazer cut stencils. They have trapozoidal shaped apertures and this could assist with the paste releasing onto y the PCB
Electronics Forum | Mon Jul 30 01:34:46 EDT 2001 | mugen
Best thing to do, is consult your solder paste supplier, bring him/her in, and ask for their humble professional opinion? If they refuse, strongly consider switching to a supplier, with responsive "humble professional opinions" to share, one that spr
Electronics Forum | Mon Jul 30 18:52:43 EDT 2001 | Brian W.
You did not provide the stencil thickness or your aspect ratio. If your aspect ratio (Aperture width/stencil thickness) is less than 1.5, the paste will not release correctly from the aperture, leaving paste in the aperture. For example, if your pa
Electronics Forum | Mon Jul 30 21:12:32 EDT 2001 | davef
"Poor release" (paste hanging-up in the stencil holes) could have three main (or combination of) causes: 1 Equipment: Stencil is too thick. Specifically, a 6 thou stencil should be OK, providing you don�t violate the area and aspect ratios in the fi
Electronics Forum | Tue Jul 31 00:48:55 EDT 2001 | Frank
Sorry I forgot to provide enough information. Stencil thickness is 6 mil Aperture width is 10 mil Aspect ratio (aperture area / wall area) = 0.72 Solder paste mesh size, type 3 (-325 +500) With this aspect ratio we can printing without any probl
