Electronics Forum | Tue Apr 27 05:10:34 EDT 1999 | Earl Moon
| Which is the preferred method for soldering a bga, adding solder paste or not? Solderpaste manufacturers say to add solder while the rework station manufacturer's say it's not necessary. | Paste is preferred by not necessary. Our studies, conduct
Electronics Forum | Wed Apr 06 11:10:47 EDT 2005 | smt_rookie
We process a double-side reflow board (10 ups). Chips and IC's on the bottom side while chips, IC's plus thru-hole connectors and IC sockets on top side (bottom side first then top side reflow). In the past, we were not encountering any soldering pro
Electronics Forum | Fri Dec 16 08:00:26 EST 2005 | jax
What you are most likely dealing with: Insufficient Pure Sn layer ( multiple causes ) Because elevated temperatures accelerate the diffusion process, the thickness of the Pure Sn layer will reduce during every thermal cycle... ( bakeing PCBs, S
Electronics Forum | Wed Jul 02 12:42:58 EDT 2003 | slthomas
Not sure how else to describe this. We've received some boards (1/2" x 3.5" x .0325" board built on panels of 24) with numerous resistors showing separation of the solder from the metallization at the top of the joint. There are 26 0805's on the bo
Electronics Forum | Fri Dec 14 13:58:07 EST 2001 | slthomas
This is one I haven't seen before (not in this context, anyway). We have an assembly that we have the SMT done out of house on, because of the high volumes. The boards have two distinct characteristics with respect to the appearance of the solder jo
Electronics Forum | Tue May 31 11:56:12 EDT 2005 | chunks
Hi Matt, Get definitive answers! Contamination on the HASL finish?: From the pix you posted, it looks like something fishy is going on. I�d reject them back to the board house and demand an answer. Most board houses and purchasing people will g
Electronics Forum | Fri Jun 04 15:04:16 EDT 1999 | Earl Moon
| I'm encountering a new problem at my new company that I haven't encountered before in my past life - and that's Wave Soldering VIA holes. | | We've been getting a rash of defects that we call in this company, "insufficient solder in VIA hole." The
Electronics Forum | Mon May 14 17:14:07 EDT 2001 | davef
First, consider checking the fine SMTnet Archives. Look for threads on "white tin", in addition to "immersion tin". We�ve had a cuppla good ones of late. Merix [http://www.merix.com] gives a good comparison of different solderability preservatives
Electronics Forum | Wed Jul 25 23:35:18 EDT 2001 | mugen
my guys SOP : Round #1 1) take double-side tape, and peel it flat to the PCB. 2) process this PCB only through P&P SMT. 3) confirm the SMD placement Round #2 4) take thin plastic sheet and tape corners flat to the PCB. 5) solder paste print over t
Electronics Forum | Wed Jul 25 23:37:11 EDT 2001 | mugen
my guys SOP : Round #1 1) take double-side tape, and peel it flat to the PCB. 2) process this PCB only through P&P SMT. 3) confirm the SMD placement Round #2 4) take thin plastic sheet and tape corners flat to the PCB. 5) solder paste print over t
