Electronics Forum | Mon Apr 14 16:21:58 EDT 2008 | ck_the_flip
Bottom-side SMT parts CAN and DO go liquidus during the 2nd reflow cycle. It could be that there was enough variability between the 2 different lot code PCBs to cause the parts to fall off. Remember wetting force determines surface tension (the abi
Electronics Forum | Tue Sep 11 22:40:26 EDT 2007 | philip_yam
We are testing SAC paste for thru-hole components in the 2nd reflow process. The solder joint is alright but some problem encountered in FR1 or CAM2 PCB after multiple times of reflow due to the temperature. We are very interested in Zn or Bi-based l
Electronics Forum | Wed Jun 13 15:56:35 EDT 2007 | ck_the_flip
I experienced this with a high-mass capacitor. I was able to turn down the bottom-side convection (around 50�C lower than each of the top-side heaters), and able to NOT lose any parts. I got the bottom-side part just slightly over liquidus, and min
Electronics Forum | Thu Jun 22 12:25:07 EDT 2000 | Boca
Jason, What Chrys said! Don't try to run the bottom cooler, tried it in the mid 80's, don't work and don't want it to work. If one side of a fab is maintained cooler than liquidus and the other side into reflow it would have an easy 40C temp diffe
Electronics Forum | Thu Apr 05 08:36:35 EDT 2001 | jmlasserre
use a solder join temperature of 200/210� whatever the pcb used (tin lead coated or osp or gold fash). 2nd ==> to adapt the temerature to the pcb used: - Reflow (200-210�) for tin lead coated pcb's (in this case we have just to reflow the solder
Electronics Forum | Fri Mar 15 08:25:42 EDT 2013 | torch
looking for a bit of advice really, our current reflow oven (surfair 510) is in the process of slowly dieing so we are in the market for a replacement. I havent followed technologies on ovens for a while but im looking for something that is low to m
Electronics Forum | Fri Apr 03 03:41:04 EST 1998 | Frank J. de Klein
150 secs. On bilayer boards (Cu only at top and bottom) you can typically not reach differences top to bottom bigger then 35-40 C. For multilayers however, the maximum is 15-20 C. If you actively cool a multi- layer at the bottom during the 2nd pass,
Electronics Forum | Mon Mar 22 09:37:28 EST 2004 | ellis
After 2nd time reflow of double reflow, wrinkles solder joints found on SOIC and SOT components.(only happen on the components at the underside of pcb during reflow, top side components dont have this problem) is this due to the reflow process proble
Electronics Forum | Tue May 14 21:07:03 EDT 2002 | ianchan
Hi mates, Yes, the lighter mass is a valid reasoning. in addition to the "lighter (mass) than thou" point of view, 1) the first reason for mounting active Parts (eg. IC, QFP, LGA...) is to minimize the temperature exposure of the Parts to a single
Electronics Forum | Mon Jul 10 11:38:15 EDT 2006 | Rob
Hi Dougs, I think I'm going to have to admit to some insider knowledge here. It kind of gave it away when you mentioned there were only catalogue pages instead of specs. http://www.anglia.com/product_search/part_tracker/index.asp I think you may
.gif)
