Electronics Forum | Thu Nov 17 20:23:55 EST 2005 | davef
We're with your customer. We believe inner layer separation is not linked to a heating excursion. What you are seeing is separation between the hole wall and the copper plating in the barrel of the hole on an unstressed PTH. Although, it's possibl
Electronics Forum | Mon Jan 10 03:45:23 EST 2022 | proy
YES there is an IPC target/acceptable spec In general terms the barrel thickness in the hole should be 1 mil (thou). IPC has an allowable limit lower around .75 with some other factors. I have been checking barrel plating on all incoming boards since
Electronics Forum | Mon Nov 19 09:34:50 EST 2007 | bbarton
Real Chunks...Yes, that's the most glaringly obvious defect in the short term (you'll probably find it on your production floor if it's really bad) but you may find that everything looks good short term only to have a high level of customer returns..
Electronics Forum | Fri Apr 15 09:56:17 EDT 2022 | winston_one
Thank's Dennis. I'm also now think in this direction. Process was adjusted and soldering are good. But one from five boards can have this effect with bubbles and strange uneven distribution of solder inside the barrel. Probably copper is too thin and
Electronics Forum | Fri Aug 18 10:55:31 EDT 2006 | Chunks
Steve, You almost got yout Man Card revoked for stating: "determining the risks associated with simultaneously applying compressive and rotational forces to the end of the barrel". Luckily you bounced back with "chewing up the copper". Just pokin
Electronics Forum | Fri Jan 21 14:51:08 EST 2000 | Dave F
Mike: I�d hate to see you making design decisions, based solely on the discussion here, but that this would be an impetus to consult IPC-D-279, "Design Guidelines ... " and take a course on designing reliable boards. Werner Engelmaier (Engelmaier
Electronics Forum | Thu Oct 16 11:15:53 EDT 2008 | davef
A good solder connection with heavy ground plane requires: * Plenty of heat [Is the preheater located too far from the wave? Whenever you look at board temperature, there is a sharp decrease in temperature between the preheater and the wave.] * Conta
Electronics Forum | Tue Feb 24 09:52:14 EST 2004 | davef
First, two points about hole / barrel fill are: * A filled hole is an excellent indicator of the optimum process and optimum quality PCB. * The study that showed that holes need not be filled was paid for by the US Army and performed by Lockheed in
Electronics Forum | Thu Jun 29 12:07:09 EDT 2017 | georgetruitt
HOW THICK IS THE BOARD? IS THERE A LOT OF COPPER IN THE BOARD? DOES YOUR CUSTOMERS PROVIDE HEAT RELIEF IN THE BOARDS BARREL DESIGN THERE NEEDS TO BE PLENTY OF ROOM FOR LEADFREE SOLDER TO FLOW, DID YOU CHECK YOUR PIN(LEAD)TO HOLE (BARREL) RATIO? N
Electronics Forum | Thu Mar 29 07:37:45 EDT 2012 | davef
The current discussion about solder fountains has to do with copper dissolution. Broadly, copper dissolution is the weakening of copper traces where a trace and a barrel plating intersect due a loss of the copper into the solder. Longer contact time
