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  • EEVblog #437 – Removing SMD Parts with ChipQuik

    Posted on March 11th, 2013 EEVblog 15 comments


    How to remove surface mount SMD QFP packages from a PCB using ChipQuik low melting point alloy solder.

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    15 responses to “EEVblog #437 – Removing SMD Parts with ChipQuik” RSS icon

      • ps: Don’t know but there might be about 10 % cadmium inside. Better wash your hands and use a fume extractor when heating up this stuff.

    • I don’t like these : messy and toxic.

      Better use hot air, you don’t need the right base, just ue a cylindric one and turn over all the pins.

      Else, there is this method : https://www.youtube.com/watch?v=tlSY1uaw0GA (works nice with QFP, just select the right wire size and enamel quality)

    • Nice video.

      There are multiple MSDS forms for various forms of Chip Quik and they seem to mention ‘one or more’ of the following combination of elements at unspecified concentrations: tin, lead, antimony, bismuth, indium, silver, and copper. The manufacturer does not list cadmium as an ingredient and cadmium is a sufficiently nasty metal that one would expect strong warnings if the product contained it.

      For me this stuff has saved a few projects and enabled a couple repairs. One project involved swapping a TSOP-54 sram chip to increase memory on a router. The product is bit pricey for sure but I try to keep a pack on hand.

      f4eru points to the enameled wire trick. That’s worked for me in the past too, but (for me) has a higher risk of bending pins or lifting pads. In any case, all these methods require some practice first.

      Regarding Dave’s question in the video about low-melting point residue being left on the pads: I worried too. After cleaning the pads with solder wick I recoated the cleaned pads with new solder and wicked them again. Unfortunately, I can’t say whether it made a difference.

      One warning: The video shows what happens if you jiggle the board while the Chip Quik is still molten. That stuff can fling everywhere but it *loves* to adhere to other solder joints. It’s a real pain cleaning it off other soldered components, so be careful if you care about the rest of the board.

    • Use the power of search and MSDS. According to their MSDS, the alloy contains Indium, Lead, Tin and possibly Bismuth. So it is not more toxic than 40/60.

      http://www.techni-tool.com/MSDS-Sheets#ChipQuick

    • We are big users of ChipQuik at my work. As you said, it is very expensive. You could have used 1/10 the amount than you actually used and would get better result — namely, you won’t have as much spatter on other parts.

      I find it is best to wait for the IC to start floating around by itself before trying to remove it. When it is ready to remove, the IC will just slid off the pads without using an external pulling device. I usually just take my solder iron at that point and just flip the chip over.

      I’ve alway been concern about changing the alloy of the solder joint. So I usually remove the left over ChipQuik using my Hakko 808 desoldering station. It found it is too easy to damage the pads with solder wick. Then I apply liberal amounts of fresh regular solder and then remove it with my Hakko 808. Then I clean the pads and install the new IC.

      YMMV

    • Hey dave,

      pet peeve: there’s no ‘n’ in isopropyl alcohol.

    • Rose’s metal looks like a closer match.

    • I’ve found Chipquick works best when you heat the chip area from *underneath* with a board pre-heater or hot air gun to 150C. You can then gently rub the Chipquick on the pins until it starts to melt. Rubbing helps mix it with the solder and you end up using a lot less.

      Heating the board from the bottom also lets you work under microscope so you can concentrate on not ruining any pads.

    • The passive at C8… gone!

    • one could also use it with a solder suck tool to suck up the combination
      one wouldn’t have to care about that glob of solder.

    • How about Field’s metal? Melts at 60 degrees C, has bismuth, indium and tin on it.

      Rose’s metal melts at ~95 degrees C, and Wood’s metal melts at ~70 degrees C plus it contains cadmium.

    • Andrew Kirkby

      Here’s a data sheet for chip quik. Notes the contents of it..

      http://www.farnell.com/datasheets/1311832.pdf

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