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I have a piece of equipment that has a CF/MD card on it. Somebody tried to force the card in and broke 2 pins off. I managed to replace the two pins temporarily, but it was kind of a hack job, but it works for now. What I want to do is order a replacement part (the part is ELCO 5620). I have a hot-air rework station but I don't have very much experience with it.

Can someone give me a run-down on technique I should use with the re-work station to remove a 50-pin CF/MD card connector. For example, what temperature to use, nozzle size, how long to heat, how to remove the component, how to prepare the site to put the new one on, etc.

Or maybe a link to a good tutorial. I have looked around for tutorials, but all I see is info about removing SMD chips and resistors, which typically aren't surrounded by easily damaged/melted plastic.

renosis
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    The following is based on zero personal experience of trying the suggestion + various reading: Use of a "hot plate" for board preheating is suggested by some manufacturers when removing more delicate SMD parts. IF you have good access under the part you may be able to provide a heat conductive standoff under the part and then place the whole assembly above a suitable hot surface (element, frypan, ...) so the standoff rests on the hot surface. OR use local heating to heat the under-board heat transfer piece. CF is only (... digs round stuff on desktop ...) about 45mm wide. ... – Russell McMahon Jan 14 '13 at 00:39
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    ... A piece of copper that size should be readily come by and cut to size and shape. Lacking anything that looks about right, a piece of copper water pipe could be cut to length and flattened with a hammer. For extra thickness use a piece twice as long as needed + a bit more and after flattening fold in two and repeat. Transfer between layers may be less good than desired. Solid copper sheet would be easier. – Russell McMahon Jan 14 '13 at 00:42
  • Thanks, I have a hot plate too. I just got it though and have never used it. So maybe I should try a few test runs first. – renosis Jan 14 '13 at 02:40

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I would remove the part in a way to concentrate on saving the board with minimal damage as opposed to trying to remove the whole socket in one swoop. If you reference the ELCO / AVX data sheet for the 5620 you will note that there are three main attachment regions for this part - The pin row and then one anchor foot on each side toward the front of the socket. First snap off the socket cover and ejector mechanism and set aside (you may be able to re-use it with the replacement socket). Then cut the side slides of the socket at the points marked in the picture below. Cut in a way that you do not put any stress on any of the solder pads. Once the sides are cut it is super easy to remove the two anchor foot pieces using a regular soldering iron.

enter image description here

Next I would cut off all the solder legs across the back of the socket. My tool of choice for that is to to use an abrasive cutoff wheel in a rotary tool like a Dremel. Cut along where I show the green line in the above picture. Use care to isolate the area of the the board so that the particulate from the cutting area does not get all over other parts of the rest of the board. This can be achieved by creating a mask around the socket using plastic electrical tape and attached pieces of paper.

Cutting like this eliminates almost all stress on the solder legs to the pads on the board. Once the legs are all cut the rest of the socket is easily lifted off the board. Clean up the dust from cutting and then finally remove the mask and electrical tape. At this point it is a piece of cake to remove each socket lead from its pad using a soldering iron and a pair of tweezers. Finally come back with solder wick and soldering iron to clean up all the pads and prepare for installation of the new socket.

Note that replacement sockets are available from Mouser Electronics for very reasonable prices.

Michael Karas
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  • Thanks, that was great! As for the replacement sockets on Mouser Electronics... are most card reader sockets pretty much the same? To replace the broken pins today I used a cheapy card reader I had laying around, but I did notice that the height of the pins came up much higher than the part I was fixing. I had to bend and trim the pins to get them to fit. I should probably get the exact same model (ELCO 5620). Mouser doesn't have it. – renosis Jan 14 '13 at 02:32
  • Oh, I just re-read your post. So ELCO 5620 is the same exact part as AVX 5620? – renosis Jan 14 '13 at 02:42
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    @renosis - From the supplier information page at Mouser it looks like ELCO may have become part of AVX. Mouser lists an assortment of connectors with data sheets that call out part number 5620 - looks pretty close to me. If you purchase one from Mouser and in the unlikely chance it ends up being the wrong thing you certainly will not be out very much money. (Especially if you purchase some other needed supplies on the same order so you amortize the shipping cost across multiple items). – Michael Karas Jan 14 '13 at 08:49