Electronics Forum | Thu May 22 12:32:35 EDT 2008 | tonyamenson
So here is my problem with the info you gave. If my preheat topside max is 150 - 170 C but my flux calls out a topside temp of 93 - 104 C..... ....Im pretty much up a creek becuase of a poor flux choice? FYI. we are using the Indium 3590-TX for bo
Electronics Forum | Wed May 21 09:03:52 EDT 2008 | bing007
I have been confronted with a MPM with a rheometric pump head on and have not had much to do with these. It is giving varying results on the down line paste AOI and is not responding very much to changes in pressure, speed etc. It is a 16inch pump, w
Electronics Forum | Fri May 23 16:38:28 EDT 2008 | wayne123
Well if you are getting bridges under, one thing that we used to do was flood the part with flux and then run it back through the reflow. Keep in mind we were not a High reliability manufacturer. This practice didn't hurt OUR boards, and most of the
Electronics Forum | Tue Jun 03 01:03:04 EDT 2008 | daxman
Hi, I think what you are describing is a half-etch QFN, which causes the 3 mil gap. In our process, we don't require solder to bridge this gap as it's internally connected to the bottom lead. I'm not sure if this is the question you're asking, but
Electronics Forum | Mon May 26 11:02:17 EDT 2008 | jandon
Hi Mr. Necdet Ozyonum, Recently we did have same kind of problems when we use lead free reflow profile for leaded solder paste (AIM WS-483). There where solder resist lacks, we found white residue after aqueous cleaning. Not in the solder joints but
Electronics Forum | Mon May 26 07:52:06 EDT 2008 | kenshiikeda
Hi mates, I encounter a problem on PCB after going thru the LeadFree Solder Wave. It shows so much dirt or dross on the PCB surface. I have attached the picture for more details. I have tried to scope out suspected solder dross and oxidedized solde
Electronics Forum | Wed May 28 09:46:48 EDT 2008 | andrzej
What I can recommend is : - clean your wave frequently, frames, etc. - looks like you have too much dross. Do you use phosphorus pills or do you have soldering alloy with phosphorus to limit as much as possible dross creation. - are you soldering
Electronics Forum | Sat May 31 09:44:56 EDT 2008 | gregoryyork
looks like the board has gone through and not actually fluxed properly,trying hand applying and it should fix it. IF it still occurs put the pallet through without pcb and without flux and see what residues come off in the wave. residues you are seei
Electronics Forum | Wed May 28 07:44:28 EDT 2008 | rgduval
Hi, AJ, In general, the peak PCB temperature is variable depending on the profile used. We try to keep our peak temperatures in line with the paste manufacturers recommended temperatures; ignoring the peak temps for the PCBs. For the peak temps yo
Electronics Forum | Wed May 28 08:46:39 EDT 2008 | ck_the_flip
I've talked to several Applications Engineers and Chemists from a couple of different paste manufacturers and they confirm that the profiles on their data sheets are nothing but guidelines. It's up to you, Process Engineer or Process Tech, to develo
