Electronics Forum | Fri Dec 01 14:12:50 EST 2000 | Jim M.
My company currently uses water soluble paste for our SMT process. We were having trouble retaining hot water in our in line, closed loop DI cleaner. The cleaner kept shutting down when the water temp. dropped below 125C. As a result, the conveyor
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
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 Oct 22 14:57:18 EDT 2002 | Jim M.
I use a water soluble flux to solder an LCD into gold plated through holes of a .031 circuit card. Problem is the current water soluble flux (850-33) is not made anymore (the drop in replacement has a different formuala and does not work). The main i
Electronics Forum | Wed Sep 08 11:04:41 EDT 1999 | Timothy O'Neill
| I am using a 18 mil and below water soluble solder paste (89.5-25-80). I have never used this type of paste. The PCB has a fine pitch component of which I cannot prevent bridging. The paste coverage on the pad looks like it is slumping. It is not a
Electronics Forum | Thu Sep 02 08:57:29 EDT 1999 | Scott
I am using a 18 mil and below water soluble solder paste (89.5-25-80). I have never used this type of paste. The PCB has a fine pitch component of which I cannot prevent bridging. The paste coverage on the pad looks like it is slumping. It is not a n
Electronics Forum | Wed Jan 12 13:42:08 EST 2000 | Tim A.
Is it possible to have a no-clean flux that could be removed with water. I would like to use a single flux at wave solder that could satisfy both no-clean and water soluble customers, within a contract manufacturing environment. Thanks, Tim A.
