Electronics Forum | Thu Jun 06 12:24:30 EDT 2002 | cyber_wolf
Brad your theory sounds good, but I have seen this happen at very low ramp rates .5 deg to 1.5 deg C rate of rise a sec. with the same soak duration you mentioned. If flux spattering is the case and you are using Alpha paste..switch to Indium and yo
Electronics Forum | Fri Jun 28 03:04:21 EDT 2002 | Dreamsniper
Forgot to include the following: Dwell time is from 55 secs to 68 secs. Indium specs for the paste is maximum peak @ 228'C and 30 to 90 secs dwell time above 183'C. PCB is a 6 layer board with Dimension of 205 x 166 mm but is slightly dense with 11
Electronics Forum | Wed Jul 31 14:08:22 EDT 2002 | Dave G
Used this paste on ENIG boards W/O N2 and had very good results. (0402's,BGA's,16mil FP) Never had the need to use N2 with this paste on our products. Running with N2 shouldn't hurt anything. The wetting properties should get even better than they ar
Electronics Forum | Sat Oct 19 11:48:39 EDT 2002 | davef
Good points, John. Continuing to track on the voiding issue, why remove voids anyhow? * Voids are primarily process indicators. There is experimental evidence that voids retard crack propagation locally around the void on at least on a temporary bas
Electronics Forum | Fri Oct 18 07:14:51 EDT 2002 | cyber_wolf
Have you tried using a paste with a more aggressive flux? Our main paste is Indium, but whenever we run into oxidized parts or have soldering problems due to oxidation on pads we use an older Alpha WS paste called WS609. The drawback of this paste is
Electronics Forum | Mon May 17 15:14:12 EDT 2004 | solderpro
Agree with Joe 100%, we recently brought one in from Malcolm for trial, this company had not practiced viscosity reading or anything in the process, the trail run was a great improvement in print, consistancy, deposition and formation of the solder b
Electronics Forum | Thu Apr 08 04:52:24 EDT 2004 | Dougie
We are concerned about the issues you mentioned and more, however we have no option but to change over due to legislation. A high percentage of our market share is in Europe and Japan, who of course have already embraced the no-lead change. We simply
Electronics Forum | Fri Apr 23 08:20:25 EDT 2004 | babe
Sometimes solder balling is related to oxidized paste or paste that has sat on the pcb too long before reflow. Mostly it is related to process, sorry... Too slow or too fast of a reflow ramp rate. Heating up an assembly too quickly will not allow the
Electronics Forum | Wed May 12 08:35:20 EDT 2004 | solderpro
yes this paste is a pain in the paste.... there are very few reasons for solderballs, component to pad ratio and placement.... solder paste control, using a mixer, not hand mixing, checking viscosity and temp..... or simply and bad profile and your
Electronics Forum | Mon Sep 27 22:25:05 EDT 2004 | KEN
Minimal cost and low melting point??? Have you bought Indium or Bismuth based alloys lately? Tin/Silver, Tin silver coper-X you name it....there are trade-offs (cost / performance). Not all are exactly published or are suitable for all appliations
