Electronics Forum | Mon Feb 19 18:57:49 EST 2001 | davef
Expanding on the limit of the portion of gold acceptable in a solder connection [mentioned in an earlier post]: The embrittlement culprit, AuSn4, is 29 weight percent gold. So even if one had 100% tin as the solder alloy and 10% gold were dissolved
Electronics Forum | Mon Mar 05 18:56:47 EST 2001 | davef
Stefan: Thanks for the clarification on the Siemens machine operation. Yes Stefan, Germany and some other countries have wonderful apprentice programs. Generally, we Americans have the patience of a staving gerbil for such things. Is the ON butto
Electronics Forum | Tue Mar 13 13:15:59 EST 2001 | kerryn
Dear Dave and Mike, I do not normally respond to threads of the forum. However, I do enjoy reading other's comments. There is a lot of valuable information provided by both suppliers and users. You seem to be making light of Bill Schreiber's com
Electronics Forum | Mon Mar 05 20:53:32 EST 2001 | davef
When you say all over the board, please give more detail. Where are they located? [All over wave soldered portion, laminate only, solder mask only, solder only, specific components only, etc] When you say white residue, what color are they really?
Electronics Forum | Tue Mar 13 20:25:39 EST 2001 | davef
So, what is not soldering? Pads er test points? I assume the holes are unsupported, right? Tell us more about the test points. Are they the kind with the little pastic shoulders [on the primary side] that keep them from falling through the hole?
Electronics Forum | Wed Mar 21 16:32:03 EST 2001 | mparker
The root cause is dependant on the type of solder "splash", ball, whatever, that you are seeing post reflow. If it is smears, then cleaning the stencil underside is probably the answer. Are you using automatic wipers? How many print cycles between w
Electronics Forum | Wed Mar 21 20:40:28 EST 2001 | dblsixes
We are building a monster ... Dimensions are 10" x 7" ... 12 layers ... A Logic Assembly with a Power Supply all rolled into one ... The Power Supply is in one section of the board, the logic in the other section ... The Power Supply obviously has a
Electronics Forum | Tue Mar 27 09:06:10 EST 2001 | dblsixes
We have tried to adjust the upper and lower heaters. We have a dillema in this area however. The power supply portion of the assembly has thermal vias in the solder pads underneath larger pads. We have a problem with solder wicking through these h
Electronics Forum | Fri Mar 23 21:36:02 EST 2001 | CAL
If you do not have any luck finding a west coast lab, but need services I am sure we can help. The only problem is we are on the east coast. Many moons ago empf was on the west coast (China Lake) but moved eastward. We are in Philadelphia, PA. (ski
Electronics Forum | Fri Apr 06 08:35:20 EDT 2001 | brownsj
You can buy plenty of paste height measuring systems today, ranging from full 3D laser systems to systems using an oblique light line which will measure the paste height only. I found that the lowest cost option was to attach a DTI to the focus contr