Electronics Forum | Tue Dec 21 17:58:44 EST 1999 | Brian W.
When doing PIH processes, it is critical that you control the solder VOLUME, not the height. You must define the process, monitor it and control chart it to keep the paste volume consistent. You have do some careful engineering to determine how muc
Electronics Forum | Mon Dec 06 05:18:53 EST 1999 | Wolfgang Busko
Hi Russ, assuming that only your flux changed and the PCB-finish stayed the same it seems to me that the solderability of that finish is somehow poor. About Ni/Au it can be said that the solderconnection is made between Ni and Sn. The Au-finish is ju
Electronics Forum | Tue Dec 07 16:34:54 EST 1999 | Russ
Wolfgang, I appreciate your continued feedback! The main reason that I shortened the Time Above Liquidous (TAL) was it appeared that I was burning off all of the flux from the paste. By shortening the TAL to 45 seconds and decreasing peak temp to
Electronics Forum | Fri Nov 26 09:13:10 EST 1999 | Wolfgang Busko
Jeff, Ted, Stefano What Stefano is saying sounds reasonable. With entry-level systems its always a struggle to get sufficient results. The operators golden hand is needed. Better controlled advanced dispensing systems should do the work, unluckily I
Electronics Forum | Mon Nov 15 21:35:50 EST 1999 | Dave F
Bob Bob: Fortunately, you found this before you built-up a lot of product. Some thoughs and other drivel: 1 Use IPC-TM-650, Method 2.4.8 for copper peel with a Instron machine. Typical pad peel strength requirement for FR-4, 2 oz. copper is: 6 l
Electronics Forum | Tue Nov 09 20:06:26 EST 1999 | Robert Culpepper
This may help you regarding the V-Groove or scored board designs. With respect to material left, I did some experiments and found that for our process .009 of material seemed to be ideal. There was minimal stress required to break the boards apart ye
Electronics Forum | Tue Nov 16 10:53:25 EST 1999 | Scott Cook
Ok, help me out here guys and gals...... I have never understood the concept of scoring on mixed technology or SMT boards. It is quite obvious to me that the potential for SMT solder joint damage through the mechanical stresses of breakout are high.
Electronics Forum | Sun Nov 07 10:54:21 EST 1999 | Steve Thomas
We're looking at redesigning our stencils to facilitate better (well, it's pretty much non-existant, so any improvement is a big leap) release from fine pitch apertures. Currently we have perpendicular walled laser cut apertures. We'll be having
Electronics Forum | Sat Nov 13 14:09:45 EST 1999 | se
First, let me say what I always say: a good chem-etched stencil will print fine pitch. Chem-etch brings trap to the side walls because its a physical by-product of the process. Because they are less expensive you can add electropolish and still save
Electronics Forum | Tue Nov 02 16:00:29 EST 1999 | John Thorup
Well...maybe. First you would have to determine what type of trays you have. Conductive, dissipative or non conductive(non static generating). Dissipative would be your best choice. In the charged body model, the sudden discharge through a conduct
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