Electronics Forum | Thu Dec 16 11:27:39 EST 1999 | C.K.
Hey Folks: I just want to get an idea how many of you use in-line or off-line visual inspection for solder paste deposition? At my company, we have one off-line, and it inspects for paste height. It's not always consistent either. Sometimes, it g
Electronics Forum | Thu Dec 16 20:41:56 EST 1999 | TNT
Hey C.K, If you are looking for inspection of the solder paste before reflow, there are many types of inspection: 1.Paste height measurements at random positions 2.3D inspection with shadow contrast capabilities based on an autocad format 3.3D inspec
Electronics Forum | Thu Dec 16 11:54:45 EST 1999 | Mike Naddra
At reflow an inert atmosphere is used to mitigate the occurance of oxidation, to me the decision weather to move from an inert atmosphere is based on several things ; PCB surface finish - are you using a HASL finish, OSP or another surface finish and
Electronics Forum | Fri Dec 17 12:09:09 EST 1999 | Boca
Outstanding advice gentlemen! To borrow Dave F's line "I'd like to take a bit of a different angle." Ie. a few wave solder specific issues If this assembly is going over wave solder then avoid vias under passive components, it invites solder bal
Electronics Forum | Sat Dec 11 12:15:21 EST 1999 | Steve Thomas
We have a pretty challenging board (2-up panel, 15"x20", 48 20mil pitch QFP 100's and 2 25mil QFP128) that gives us LOTS of lead bridging on the 20 mil parts. There is typically very poor wetting on these parts also, and some joints just flat aren't
Electronics Forum | Mon Dec 13 05:43:27 EST 1999 | Wolfgang Busko
Hi Steve, 20 mil pitch shouldn�t be that problem nowadays. In your case bridging and poor wetting seem to go hand in hand. For the poor wetting try to eliminate it by using different paste (higher activated) and work on your profile. Coplanarity also
Electronics Forum | Thu Dec 09 13:37:35 EST 1999 | Mike F
Does anyone have a suggestion for soldering boards with 1 inch long leads sticking out the bottom? Our vendor is using a drag solder machine, but I'm not happy with the preheat and controls on it. We assemble boards with numerous LED's( 200 to 700 pe
Electronics Forum | Wed Dec 08 04:19:16 EST 1999 | pascal MATHIEU
I am working in electronic automotive industry and today we are facing to a very serious problem : if we want to use a PCBoard with a copper thickness of 90�m + fine pitch circuit (0.65mm, 0.5mm) the supplier(several) of the PCB has some trouble t
Electronics Forum | Tue Dec 07 08:11:04 EST 1999 | Wolfgang Busko
Hi Russ, there�s something I don�t understand about the measures you took. I guess that TAL means time above liquidous and shortening of that time can result in bad dissolution of the protective Au-layer. The necessary time for the Au to mix with you
Electronics Forum | Fri Dec 03 03:58:12 EST 1999 | Wolfgang Busko
Hi Charly, For batch ovens there is no discussion. For inline loading interval depends on the oven you use, the amount of heat the PCB takes out of the zone and the capability of the oven to get it back in. The approximate time for the PCB to stay i
