Electronics Forum | Thu Jul 03 08:40:23 EDT 2003 | Kris
Hi, undercured solder resists may be a defect people have seen so far. Some of the probles arising is blistering as well as reaction with wave solder flux that may lead to some kind bad gel like formations. Gels the idea would be to reflow the ba
Electronics Forum | Wed Jul 09 19:05:06 EDT 2003 | randywomack
LOZ. Under-cured or out-of-spec(sloppily) applied resist is realistic. What other physics: Shiny resist surface is more prone to balls then matte finish. How about an operator eating fish & chips before handling the boards. Don't laugh... ... saw th
Electronics Forum | Thu Jul 03 15:03:39 EDT 2003 | Jim Nunns
My design group wants to change our route keep out around all SMT parts to 5 mil even under the parts with zero standoff. Are others in the industry routing under parts that have no standoff? My fear is that we will get shorting if the mask is scaped
Electronics Forum | Thu Jul 03 15:29:46 EDT 2003 | bpan
Hello Jim, We build boards that have traces under the parts all the time. For the most part, we have no problems but on one product we have an 0805 that bridges 2 traces with a very tight seperation and if any solder smears (under the part)we can and
Electronics Forum | Wed Jul 09 11:58:03 EDT 2003 | sam
When we try another test by using less solder paste, we found under the microscope that the solder was actually stick on the LED gold surface, but not having good wetting. By this finding, we can basically conclude that it was poor solderability caus
Electronics Forum | Wed Jul 09 13:48:03 EDT 2003 | russ
Sam, You may want to be careful with your analisys, reducing paste volume also reduces flux volume. Flux is there to promote and aid in wetting. by reducing flux you may have initiated the poor wetting yourself with the experiment. Just anothe
Electronics Forum | Fri Jul 04 19:39:08 EDT 2003 | AlCapone
i'm newbie to this forum, I have a question about Cp and Cpk, nowaday, what number of ppm your company targets. Also as a SMT engineering you guys operate the whole smt line from SPM to ICT, has your company let you calculate the Cp and Cpk or there
Electronics Forum | Fri Jul 25 13:12:22 EDT 2003 | Bill
Brad, If you are considering ERSA equipment, we have a 2001 ERSA Versaflow High Speed Selective Solder Machine for sale. Please contact me at b-morgan@carolina.rr.com or call me at 704-795-6610 Ext 13 if you would like details. Also, please visit ou
Electronics Forum | Wed Jul 09 15:54:51 EDT 2003 | Louis
I need advice from someone who has already soldered this part or similar fine-pitch BGA with metal heatsink on top Should I solder it in the oven or it's better with a rework station (IR 550A Ersascope) Thanks All
Electronics Forum | Thu Jul 10 15:05:30 EDT 2003 | stepheno
Don't forget about moisture sensitive devices already on the board if you are reflowing the entire board again. No doubt the other BGA's have been absorbing moisture since the boards were first reflowed. You may have to bake the boards before reflo
