Electronics Forum | Fri Oct 18 16:24:05 EDT 2002 | russ
Big BIG BIGG wave with a lot of preheat capability both top and bottom. You may need to exceed the standard "100 C" top side preheat to 120C or so (be aware of any topside SMT going into reflow over the wave). A spray fluxer with very fine atomizati
Electronics Forum | Mon Oct 21 11:49:20 EDT 2002 | sueph
Mike, We are currently wave soldering several assemblies with with a lot of ground plane. The soldering handbook we have in house suggests a preheat temp for metal core multilayer boards of 230 to 270 degrees F' (110 to 130 C'). It was scary at fir
Electronics Forum | Fri Oct 18 12:55:12 EDT 2002 | mmulgrew
We are currently experimenting on an 18 layer 2 oz. copper backplane. The spec is calling for 100% solder joint top to bottom. Any input greatly appreciated.
Electronics Forum | Thu May 15 17:34:17 EDT 2014 | taiji
I always made tests with gauges on top or bottom surface of the PCB, before, during and after the process that we wanted to check. But I never tried to do it on internal layers of PCB. Don't know if that is possible. Regards
Electronics Forum | Fri May 16 05:17:13 EDT 2014 | julianf
Interesting. How did you connect the gauges in the press? Our press only has connections for thermocouples. But in essence, it's only a wire and an electical output. If you placed these prefabricated gauges on top and on the bottom surface, weren't
Electronics Forum | Mon May 26 04:39:49 EDT 2014 | sarason
Damn near impossible. You need to see a real change in the difference between the 2 elements you are reading. So to give yourself any hope run 2 long traces one top one bottom up the length of the board. Then compare to 2 wriggly traces at one end (o
Electronics Forum | Mon May 26 03:27:00 EDT 2014 | julianf
Thanks for your reply Sarason. I'm aware now that my goals seem very ambitious and infeasible. Let me formulate my problem in an different way that might be more realistic. Is it possible to measure a DIFFERENCE in strain between top and middle la
Electronics Forum | Thu Jul 31 15:41:23 EDT 2003 | davef
Q: Could any of you guys tell me what exactly is this greenish thing ? A: No, but is not copper oxide. Copper oxide is brown, the color of a penny [here in the US] or an untreated copper laminated trace on a board. Many copper salts are greenish in
Electronics Forum | Fri Aug 21 12:54:21 EDT 1998 | Tryin' and Learnin'
HASL: (hot air solder leveling) is a process used to cover the Cu. Either Sn/Pb is used or Ni/Au or some other combo. In one case you create a land pad and in the other (with resin)you cover the Cu so that you only have a "trace." Is that correct so
Electronics Forum | Fri Aug 21 14:29:37 EDT 1998 | Earl Moon
| HASL: (hot air solder leveling) is a process used to cover the Cu. Either Sn/Pb is used or Ni/Au or some other combo. In one case you create a land pad and in the other (with resin)you cover the Cu so that you only have a "trace." Is that correct s
