Electronics Forum | Thu Jun 24 14:34:13 EDT 2004 | tjensen
There are many factors that can lead to solder balls. Since you have just recently seen this start to occur, it is obvious something has changed in the product or your process. Since we don't have a lot of details about your process, I would sugges
Electronics Forum | Mon Feb 07 12:47:18 EST 2005 | Indy
1. use 6-7mils stencil. 2. reduce aperture opening to 60-70% of pad size. 3. check viscosity of solder paste. According to that you might want to alter your print speed and pressure. Cheers Indy
Electronics Forum | Mon May 14 16:52:19 EDT 2001 | John
We have been running a product for the past several months using Loctite 3615 in our adhesive dispenser (Camalot 3800). The program the machine has been running has gone unchanged for quite some time now and everything has run well. Today, it appea
Electronics Forum | Tue Jan 25 20:19:24 EST 2000 | Charley Qin
Hi, Mark Acturally, solder paste viscosity reading is very closely related to eviroment such as temperature and relative humidity. So I'm afraid it is hard to tell the diffrence between measurements without enviroment control. Regarding to LSM, we'v
Electronics Forum | Sun Sep 27 22:39:55 EDT 2009 | rajeshwara
The same issue i faced 2 yrs before , i sugest 1. Use stencil of 4 mils ( Take care of Aspect Ratio and Area Ratio ). 2. Use Solder Paste of Type 4.5 and Viscosity in between 1100 to 1300. ( Try Solder Paste of Cookson or Alpha metals : OM338 T45-L
Electronics Forum | Wed Aug 23 17:06:40 EDT 2000 | Dr. Ning-Cheng Lee
For 20 mil pitch pads, the volume control is more critical in terms of bridging concern. In general, solder paste for dispensing is more prone to slumping due to low metal load and low viscosity. If the volume dispensed is on the high end, or if the
Electronics Forum | Mon Sep 25 10:18:00 EDT 2000 | Vic Lau
Dear Friends, I am handling a new project, and search for a solder paste stencil printer (automatic or semi-automatic) for lead free solder paste. The one I had looked for is MPM3000 series, however, what I heard from other freinds, those model is
Electronics Forum | Thu Jan 20 14:28:49 EST 2000 | Scott S. Snider
I ran this test back in '92 or '93 when Alpha was first pushing to change from Brookfield to Malcolm readings. The correlation between Malcolm readings to solder paste height is good. I could always look at the viscosity reading and know at least a d
Electronics Forum | Fri Feb 21 19:41:25 EST 2003 | neil
I have had a look at what Bob Willis say's and the answer to my problem is not there. The paste we are using has a very high viscosity and I beleive that if we reduce the metal content to less than 90% it will solve the problem. The problem is parti
Electronics Forum | Wed Feb 14 10:10:55 EST 2007 | rob_thomas
The challenge regarding the stencil was mostly due to the actual board layout and nothing having to do with the voids in the solder. It was my first encounter with 0.5 mm pitch on BGA and dealing with a LF solder paste with higher viscosity than tha
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