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 | Mon Mar 22 10:24:03 EST 2004 | davef
Wrinkled like orange peel?
Electronics Forum | Wed Mar 24 08:36:58 EST 2004 | Evtimov
Hi! What exatly you do? Do you reflow the both sides of the board at the same time or you reflow your second side? I think in both cases you should decrease you bottom zones. If you reflow both sides - with 10-20C(F) If you reflow the second side - w
Electronics Forum | Mon Mar 22 19:46:17 EST 2004 | pdeuel
The bottom side is going into reflow somewhare near melting point of solder. Reduce bottom side temprature. Get a good mole so ramp and soak tempratures can be checked on bolth sides of the PCB. The object is to keep bottom side parts from approching
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 | Tue May 07 22:25:15 EDT 2002 | L_ch
Hello, As you know for the double side assembly PCBs, we normally first place the bottom side, then place top side after reflow soldering of bottom side. are there any other considerations for the sequence of reflow soldering ( bottoms side first, to
Electronics Forum | Mon Oct 04 07:47:34 EDT 1999 | park kyung sam
| | What are pro's and con's of reflowing top side first and curing bottom side chip components, and then wave soldering bottom side? | | | | How about curing bottom side first and reflowing top side later? | | | | What percentage of companies run
Electronics Forum | Fri Apr 09 09:08:40 EDT 2010 | cast2010
Hello, I produce two types of board. - 100% Thru Hole - 50% thru hole and 50% SMT For the second, I have a bad wetting after the reflow on the top. The pcb board have Au-Ni pad. I use a water soluble paste. I clean the board with a solution with
Electronics Forum | Fri Jun 26 14:08:49 EDT 2020 | indhu
Hi, I am having a issue that SMT nut drop after reflow. The solder height all in specifications. Had tried adding flux inand the solder paste. But shows no improvement. Is the nut easily oxidize? Can anyone help me on this?
Electronics Forum | Fri Jun 26 14:27:51 EDT 2020 | victorzubashev
Hi Indhu, It could be multiple reasons but probably one root cause. metal nut might require reflow profile change- you need to check it with SMT reflow profiler. the part might be oxidized - you can check solderability or try to solder part using a
