Electronics Forum | Wed Jan 18 02:00:36 EST 2006 | pavel_murtishev
Good morning, This isn�t very strange. Bottom side components are prone to tombstoning more than topside ones. Try to reduce oven�s bottom heaters temperature slightly to prevent solder paste melting on bottom side. This can help. BR, Pavel
Electronics Forum | Tue Jan 17 11:52:07 EST 2006 | pms
Got a wierd one here, 0402's tomb-stoning. Scenerio---- Double sided PCB, paste both sides, 0402 on both sides. Reflow bottom side first--- no problems. Reflow topside next----no problems with topside components, BUT, the bottom side that was ref
Electronics Forum | Thu Aug 06 09:51:20 EDT 1998 | Bob Willis
This text may be of interest to any one with tin lead spots Guide to Solder Spots - A New Plague in Manufacture ? So what are solder spots ? They appear to be the next big problem in modern reflow assembly in fact in any process that involves solder
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 | Tue Feb 27 15:20:03 EST 2007 | slthomas
Put 'em all on one side unless you have a reason to split them up.
Electronics Forum | Mon Jun 07 14:47:22 EDT 2004 | Mark
It matters on how you setup your oven profile. I have placed J-leads on both sides with no problems. Also, have come across some fine pitch but wouldnt suggest this too often. Give some examples that he would like to see placed on the bottom side of
Electronics Forum | Wed Aug 04 17:16:13 EDT 2004 | Richard
Can anyone comment on inspection criteria for PIH applications. I'm of the opinion that the inspection criteria used for wave soldered joints should be used for PIH. Some colleagues believe that a bottom side fillet is not necessary since the solde
Electronics Forum | Thu Oct 11 17:44:30 EDT 2001 | aaelect
OK, OK. 672 ball BGA. The pcbs are PC Card bus size and are .015 thick. There are 3 on a panel with about 1/2" between and rails. The aluminum plates are about 3" by 7". There are 3 cutouts which allow for the parts from either side to protrude du
Electronics Forum | Wed Apr 06 12:36:53 EDT 2005 | smt_rookie
I've tried a different lot of the same double header connector (yes its double level right angled header conector) twice but nothing has improved. I've also suspected that top row of the connector has greater heat sinking capacity (which should hold
Electronics Forum | Tue Feb 27 15:23:53 EST 2007 | jdengler
As already stated one side. Also if at all possible change the through hole components to SMT. It is much cheaper to assemble SMT than through hole. Jerry
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