Electronics Forum | Tue Jun 28 18:20:49 EDT 2005 | russ
Matt, have you run a profile on this board? Just because it's .062" doesn't mean that any old .062" profile will work. We have .062" thick boards that almost nil for copper and other are utilizing 2 oz. layers internally. They require quite diffe
Electronics Forum | Tue Jun 28 09:39:00 EDT 2005 | davef
Points to consider are: * Gold plating too thick [SB LT 8 uinches]. [Obviously, we're talking about actual plating thickness, not the specification.] * Reflow recipe improper [SB 220*C 5-10 sec]. A recipe that works fine for HASL needs to be hotter
Electronics Forum | Tue Jul 11 12:59:26 EDT 2006 | mattkehoe@sipad.com
We are trying to apply solder to boards with 80 microinches of electro plated hard gold. No components involved, just print 63/37 paste and reflow. The results are very poor on some boards, not so bad on others? Pictures at http://www.sipad.net/thick
Electronics Forum | Wed Jul 12 11:26:12 EDT 2006 | flipit
Hi, I believe you have classic gold imbrittlement here. With 80 microinches of gold you are way over the limit. You can try to reflow longer time and at a higher temperature. The gold does not melt into the solder joint. The gold dissolves into
Electronics Forum | Tue Jun 28 13:23:56 EDT 2005 | Bob Gilbert
Matt, Try a cooler profile by simply speeding up the conveyor by 10%. The difference may be the temperature the pads are reaching between the HASL boards and the Au boards. Are they the same thickness?
Electronics Forum | Wed Jul 12 11:46:00 EDT 2006 | flipit
Hi, One other note. You don't want gold to be more than 1% to 2% of the the solder joint. Above this percentage you will have embrittlemant issues. Lots of information on gold embrittlement on this site and on the Internet. I estimate your produ
Electronics Forum | Tue Jun 28 16:41:07 EDT 2005 | mattkehoe
Yes, .062 fr4. Like I said before, we run a lot of gold boards, as many as 25% of what goes through the shop, and we've never adjusted anything before??? Many of these are bigger by 2 X and much more dense. Reflow is not as shiny as HASL but always u
Electronics Forum | Tue Jun 28 10:51:32 EDT 2005 | mattkehoe
Thanks for the replies, - solder paste used ? NC ? other ? Water soluble 63/37 paste - reflow in Air or N2 ? Infrared - temp ramp up before soack (�C/second) ? Will have to check. This profile has been used on numerous gold plated boards in our
Electronics Forum | Tue Jul 11 20:13:05 EDT 2006 | davef
We agree with Chunks. You need to turn-up the heat [slow the conveyor] because you have significantly changed the melting point of the solder alloy by adding so much gold. Relative to ENIG you should expect: * Similarly smooth surface, possibly a l
Electronics Forum | Wed Sep 01 08:27:38 EDT 2004 | davef
Zinc from the brass [Cu3Zn2] diffuses into the tin causing solderability problems. Just 0.001% of Zn in your solder can render it fit for the scrap heap. So, you need a barrier plate between the brass and the tin. Copper or nickel-plating is commonl