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"pfjw@aol.com" <pfjw@aol.com>: May 02 08:03AM -0700 On Sunday, May 1, 2016 at 8:17:56 PM UTC-4, Danny DiAmico wrote:     > Do you think if I put in a new board, that it will also blow?   First, the capacitor visible from the top is toast - the top has clearly swelled, a condition that is typical of a short.   The one large trace looks like a fusible link designed to fail, which, of course, it did. But, that is also likely to be a coincidence rather than an actual design element.   And you also lost a disc cap - that is quite unusual and takes onehelluva spike to accomplish. Which would also explain the fried resistors. Replace it with a new cap of the same value, but with a rating of at least 400V, 600 being better.   There is lots-O-SMT stuff going on, a major PITA to repair unless you have steady hands and good eyesight. Not impossible, but not easy.   I would try to repair the board first - unless a replacement is cheap and time is of the essence. Replace BOTH large electrolytic capacitors, go up one rating (at least) in voltage, and also look for a higher temperature rating than OEM, if one will fit.   You will need to find out whether the resistor near the burn is still good, and its value (don't assume) before you replace it and rebuild the burnt trace. On the long trace, some copper foil will do, solder it to the burnt ends and then trace it over with solder. Once that is done, a bit of CA to hold it to the board will finish the job.   As to putting in a new board, unless you check the ingoing and outgoing voltages, there is no guarantee that there was not an outside cause. But given the appearance of the electrolytics, I suspect they are the first cause.   Peter Wieck Melrose Park, PA

Danny DiAmico <dannydiamico@yahoo.com>: May 02 03:45PM On Sun, 01 May 2016 19:04:35 -0700, Oren wrote:   > Danny, your pics are to large. Thin the megs down. Your's choke my > bandwidth. Not normally a concern for me.   I'm sorry. From my experience with you guys, you *see things* I don't see when I show you pictures (remember the garage door frame rebuild?).   So, I wanted you to have the *biggest* pictures I could supply, so that you guys could zoom in.   As a courtesy to you all, who help me immensely, here are the shrunk pictures, in the order of most important to least important.   This is the motor control board (PN 8540540, also PN W10163007) for the Whirlpool Duet Sport WFW8410SW washing machine: http://i.cubeupload.com/k1m0mV.jpg   Notice that traces are burnt: http://i.cubeupload.com/k7Hwkl.jpg   And that multiple surface-mount components have exploded: http://i.cubeupload.com/YGQ9cM.jpg   There is even a "bullet hole" in one of the flat devices, which, might not be a capacitor because it's labelled "R16" whereas the other capacitors have a "C" designation as per typical convention: http://i.cubeupload.com/RfF0Bv.jpg   I'm not sure if one of the huge electrolytic capacitors has blown or not, because the top isn't flat, but I don't know if it was flat to begin with: http://i.cubeupload.com/vdL6Ut.jpg   The other huge electrolytic capacitor seems OK though: http://i.cubeupload.com/tb3cu4.jpg   The part number is clearly shown on this sticker (and a call to the official Whirlpool parts center (866-698-2538) confirms that the part number W10163007 and 8540540. (It's important to note that the part number is not W10205342, which is sometimes listed in the parts diagrams - that must be for a newer model?) http://i.cubeupload.com/ErHVuc.jpg   I'll repost the shrunk pictures of the CPU board and the EMI filter separately, but they seem pristine so I don't think the problem is there (unless they caused the problem in the first place).   Let me know if these pictures need to be shrunk further as I do try to document everything not only so that you guys can help me, but also so that others benefit from each action we take.   PS: Where is Jeff Liebermann when you need him!

Danny DiAmico <dannydiamico@yahoo.com>: May 02 03:52PM On Sun, 01 May 2016 21:33:07 -0700, Uncle Monster wrote:   > appliances. I haven't checked recently but I once could buy > rebuilt electromechanical timers for appliances. > I hate wasting things but it's often cheaper to replace a control board.   We did have rains here in California, as Jeff Liebermann would know, where the wind blew out the power in the mountains three time in one week.   So this was the *first* time the washer was started after the power went out multiple times!   And you are correct that the part I thought was a capacitor is not labelled with a C (as the rest of the caps are), but it's labelled R16, so, it's not a cap. http://i.cubeupload.com/RfF0Bv.jpg   The rest of the capacitors on the motor control board seem to be ok: http://i.cubeupload.com/TWiBYR.jpg   But certainly some of the surface-mount components have fried: http://i.cubeupload.com/xRnjw9.jpg   The good news is that the EMI suppression filter seems to be intact: http://i.cubeupload.com/ONiqvC.jpg   And the main computer control board (CCU) seems to be in good shape: http://i.cubeupload.com/qABhEj.jpg   Nothing seems burnt on the CCU: http://i.cubeupload.com/zBAmq5.jpg   So, now my goal is to see where the best place to get a used or rebuilt or new Motor Control Board (MCU) P/N W10163007 or PN 8540540 from: http://i.cubeupload.com/ErHVuc.jpg

ohger1s@gmail.com: May 02 08:37AM -0700 On Sunday, May 1, 2016 at 5:53:42 PM UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558     Other than the shape of the boards, they're not much alike. The 8060 has no flexible membrane circuit.   For the heck of it, I took a straight edge and a sharp razor and removed about a 16th from both sides of the rubber conductive strip, and still no continuity whatsoever, so I hard wired the display.   It now starts, boots, and passes the power up test. The display is clear and has full contrast.   The problem is that it's reading voltages and resistances that don't exist, even though it does read my test voltages and resistances. I guess I have to take this apart again and do a better job of cleaning the electrolyte off the board.   The link posted by an earlier poster shows problems with leakage below the main chip/socket only. If I knew that would be the only problem to address, I'd pull the socket and try it. The problem is is that every individual solution requires undoing the display hardwire, so I'm trying to formulate a plan to effectively clean this in one shot.   John John

ohger1s@gmail.com: May 02 08:38AM -0700 On Sunday, May 1, 2016 at 5:53:42 PM UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   Other than the shape of the boards, the 8026 and 8060 are not much alike. The 8060 has no flexible membrane circuit.   For the heck of it, I took a straight edge and a sharp razor and removed about a 16th from both sides of the rubber conductive strip, and still no continuity whatsoever, so I hard wired the display.   It now starts, boots, and passes the power up test. The display is clear and has full contrast.   The problem is that it's reading voltages and resistances that don't exist, even though it does read my test voltages and resistances. I guess I have to take this apart again and do a better job of cleaning the electrolyte off the board.   The link posted by an earlier poster shows problems with leakage below the main chip/socket only. If I knew that would be the only problem to address, I'd pull the socket and try it. The problem is is that every individual solution requires undoing the display hardwire, so I'm trying to formulate a plan to effectively clean this in one shot.   John

"pfjw@aol.com" <pfjw@aol.com>: May 02 05:26AM -0700 On Sunday, May 1, 2016 at 10:01:04 PM UTC-4, Phil Allison wrote:   > https://en.wikipedia.org/wiki/Gold_plating#Soldering_issues   > http://www.indium.com/blog/intermetallics-in-soldering.php   > .... Phil   Phil:   Jewelry grade gold electroplate uses a three-metal process, first copper, then nickel, then gold. Electronic plating for other than switches and mechanical connectors DOES NOT go through this process as it would be far too costly, take too much time and often add too much thickness. We are discussing microns here, and they matter. Nor is appearance a concern. For flash plating electronic solder connectors, the gold is deposited directly on the copper.   http://download.springer.com/static/pdf/727/art%253A10.1007%252FBF03215398.pdf?originUrl=http%3A%2F%2Flink.springer.com%2Farticle%2F10.1007%2FBF03215398&token2=exp=1462192837~acl=%2Fstatic%2Fpdf%2F727%2Fart%25253A10.1007%25252FBF03215398.pdf%3ForiginUrl%3Dhttp%253A%252F%252Flink.springer.com%252Farticle%252F10.1007%252FBF03215398*~hmac=b8746d004d5b115705ea43a04cfe7c2dce17925447f5ab4a1bf7e5a965d0d81b   Is a link that will take you to an article on how gold operates at/less than one micron of thickness - whereupon you are correct, and at greater thicknesses, where the solder simply does not stick.   Gold is a wretched soldering base for electronic purposes using traditional tin-based solders. As I stated previously, for any number of reasons, some not obvious.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: May 02 05:45AM -0700 > Phil:   ** That is patronising and offensive.   Address all posts to the NG.     > Jewelry grade gold electroplate uses a three-metal process,     ** Wrong topic.   > For flash plating electronic solder connectors, the gold is > deposited directly on the copper.   ** Is it ?     > Gold is a wretched soldering base for electronic purposes using > traditional tin-based solders.     ** That is a dramatic about face, if I ever saw one.       .... Phil

"pfjw@aol.com" <pfjw@aol.com>: May 02 06:21AM -0700 On Monday, May 2, 2016 at 8:45:29 AM UTC-4, Phil Allison wrote: > pf...@aol.com wrote:     > ** That is a dramatic about face, if I ever saw one.   Please show me where I have _ever_ endorsed, suggested or implied that gold is a useful soldering base for any sort of electronics purposes?   NASA has used gold as a soldering base in space and on the moon due to its tolerance of extreme heat, but they had to go to extraordinary lengths to make it reliable mechanically. Otherwise, not so much. Hence the cost per cubic centimeter of NASA equipment exceeds even that of the US military.   Silver-solder (real tin-free silver solder) is fine for gold, and why it is used for jewelry making. And as I also stated, silver brazing is more accurate as a flame is necessary typically - and in most cases, a flame is not appropriate for electronics.   Further to this, if one looks at what happens to very thin (=<1 micron) the gold "leaches" rather than dissolves - and may be easily recovered by any number of methods, not typical of a true solution. The heat breaks the plate bond to the copper substrate and the colloid so formed is very brittle.   http://mysite.du.edu/~jcalvert/phys/copper.htm   gives much more information on the chemistry (or lack thereof) of gold and as it compares to the other "noble" metals.   Peter Wieck Melrose Park, PA

ggherold@gmail.com: May 02 07:58AM -0700 On Saturday, April 30, 2016 at 2:00:53 PM UTC-4, Jon Elson wrote: > > Rohs part. > OK, just for your own use, you can do repairs with PbSn solder on assemblies > made originally with Pb free. I do this all the time, never had a problem.   Me too, the amalgamate talk makes me wonder though.   George H.

bitrex <bitrex@de.lete.earthlink.net>: May 02 07:47AM -0400 > I have been known to use a silver-plated sewing needle, broken off to the proper length if copper would be too soft. They solder very nicely.   > Peter Wieck > Melrose Park, PA   Excellent, will try. Thanks!

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