Electronics Forum | Thu Oct 28 18:14:51 EDT 1999 | John Thorup
Try looking for paste contamination somewhere. Dirty stencil, printer table or fixtures. Placement table/fixtures. Reflow belt/conveyer. Reuseable finger covers, if used. Try covering the fingers with Kapton tape during different stages of the proc
Electronics Forum | Mon May 18 17:59:06 EDT 1998 | Richard Jackson
I've tried every thing I can think of. Do you have any Ideas? What I have is micro balls on the gold fingers of panelize boards. These balls only appear on the gold finger. Or at least I can only find them on the gold fingers. What I have tried so
Electronics Forum | Mon May 18 21:29:38 EDT 1998 | D.Lange
| I've tried every thing I can think of. Do you have any | Ideas? | What I have is micro balls on the gold fingers of | panelize boards. These balls only appear on the gold | finger. Or at least I can only find them on the gold | fingers. | What I
Electronics Forum | Tue May 19 12:29:59 EDT 1998 | Richard Jackson
| Richard, | You may be encountering solder paste contamination | on the assembly during the printing process. Solder | will reflow on tin/lead plated lands therefore invisible. | If you are washing the assembly prior to inspection | then you are
Electronics Forum | Mon Aug 13 08:04:43 EDT 2007 | davef
Search the fine SMTnet Archives [on gold finger], while you're waiting for others to reply. For instance: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=42759
Electronics Forum | Sun Jul 26 20:56:43 EDT 1998 | Masdi Muhammad
We are trying to reduce the number of units fail at system test due to flux on gold finger. We know so far that the flux is deposited onto the goldfinger during touch-up or rework and to reduce the contamination we are planning to implement 'tapin
Electronics Forum | Thu Jul 20 05:04:30 EDT 2006 | bing007
We had a similar problem with gold contact pads. Cleanliness is paramount. If you are using foil tensioning system, wash the foil in a stencil wash before use as the cardboard cassettes may be contaminated. Be very careful when loading into a frame f
Electronics Forum | Wed Nov 15 07:21:58 EST 2017 | stephendo
You don't clean contaminated gold fingers so much as you replace them. I once had the "cleaning" solution. It totally dissolved the gold fingers so that they could be replaced.
Electronics Forum | Mon Feb 05 20:43:27 EST 2001 | davef
1 Solder on gold fingers comes from: 1a About 70 % of the time it's caused by poor cleaning of screen printer, staging area (table), conveyor, reflow oven chain or belt, and keeping boards separate from cleaning process 1b After loading paste onto
Electronics Forum | Mon Nov 13 13:49:16 EST 2017 | slthomas
Preemptively you can apply Kapton tape to protect the gold fingers during reflow. I think that's what most people do. After the fact, there are services available to clean them up but as it was described in another thread here, it is not in-expensiv
