 
| Subject: | |
| From: | |
| Reply To: | TechNet E-Mail Forum. |
| Date: | Fri, 10 Aug 2001 13:24:50 -0500 |
| Content-Type: | multipart/mixed |
| Parts/Attachments: |
|
|
I wonder if the bumper/dirty solder isn't a dross residue from the solder pot. This is a common issue if the solder pot motors aren't strong enough or the maintenance of the machine doesn't include regular dross removal. Profile is determined by a lot of factors. The wave profile is going to depend on the components used, ground/power planes, workmanship class of the end product, flux used, and wave machine configuration (dual, single wave, chip wave, nitrogen or not, etc.). Can you supply some more process information? Prebaking of PCB's that we have performed are (for standard .062" FR4 boards) is typically at 60-70C for 2-4 hours depending on the storage and age of the PCB.
Hope this helps.
Kathy
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META content="text/html; charset=iso-8859-1" http-equiv=Content-Type>
<META content="MSHTML 5.00.2919.6307" name=GENERATOR></HEAD>
<BODY style="FONT: 10pt Haettenschweiler; MARGIN-LEFT: 2px; MARGIN-TOP: 2px">
<DIV> </DIV>
<DIV> </DIV>
<DIV>I wonder if the bumper/dirty solder isn't a dross residue from the solder
pot. This is a common issue if the solder pot motors aren't strong enough
or the maintenance of the machine doesn't include regular dross removal.
Profile is determined by a lot of factors. The wave profile is going to
depend on the components used, ground/power planes, workmanship class of the end
product, flux used, and wave machine configuration (dual, single wave,
chip wave, nitrogen or not, etc.). Can you supply some more process
information? Prebaking of PCB's that we have performed are (for standard
.062" FR4 boards) is typically at 60-70C for 2-4 hours depending on the storage
and age of the PCB.</DIV>
<DIV> </DIV>
<DIV>Hope this helps.</DIV>
<DIV>Kathy </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV></BODY></HTML>
|
|
|
