Electronics Forum | Wed Jul 19 17:34:25 EDT 2000 | Deon Nungaray
Craig, I'd be really hesitant in pursuing this method for a TQFP. Remember, most SMD's are rated for a maximum rising slope of around 4C/Sec. Immersing a fragile TQFP in a hot wave of molten solder will probably exceed this ramp up rate. Besides thi
Electronics Forum | Thu Jun 27 11:22:03 EDT 2002 | robbied
Hi there. We have had an out of control reflow oven that has allowed its temperature to fluctuate by up to +/- 20 deg C from set point in very short periods of time. We found the root cause of the problem and fixed it, but by then we had already run
Electronics Forum | Fri Apr 21 14:58:04 EDT 2023 | rgduval
I mean...there are a ton of possibilities for bridging on selective solder before you ever get to alloy purity. Are the bridges happening consistently in the same spot? Are the leads too long? Can you modify the approach/exit/peel off to address? Wh
Electronics Forum | Mon Dec 17 19:01:45 EST 2007 | bbarton
As someone with a LOT of experience with the "low cost" alternative alloys, primarily SACX, I have one simple question....Are these shorts a new phenomena? WAS your process in control, and all of a sudden it's not? If the answer is YES, take a look a
Electronics Forum | Tue Aug 20 08:48:07 EDT 2013 | proceng1
If the parts are hand placed and hand trimmed, why do you need to inspect whether the lead is in the hole. The operator should be inserting the part correctly. We have MIRTEC machines and they do a pixel comparison to "known good images". With a m
Electronics Forum | Mon May 24 13:33:46 EDT 1999 | Dave F
| We are running a number of boards with 8-10 25 mil PQFPs on board. Our process is mature with at least 3 years experiance and statistically few opens on the QFPs. Our beloved purchasing department has chased the almighty $ and changed FAB vendor
Electronics Forum | Thu Nov 19 09:32:52 EST 1998 | Earl Moon
| | | | | | For some as yet unkown reason, we have started to have some boards sag and go under the wave. The boards are surface mount top side and conventional components wave soldered. We have checked the wave hight and both the profiles on the wav
Electronics Forum | Thu Nov 19 09:55:47 EST 1998 | Dave F
| | | | | | | For some as yet unkown reason, we have started to have some boards sag and go under the wave. The boards are surface mount top side and conventional components wave soldered. We have checked the wave hight and both the profiles on the w
Electronics Forum | Thu Jul 20 12:51:50 EDT 2000 | Tekguy2000
We are currently running boards with resistor paks on the solder side of the board introducing these to the wave solder. We cannot get rid of shorting between the leads. We are using a water soluble acohol based flux. The option of going to selective
Electronics Forum | Thu Aug 08 08:30:59 EDT 2013 | benreben
Hi, i use saki AOI and he have special algorithm for inspect TH that analyse presence of pin,angle of filet and short above the round of solder...
