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I want a simple programming jig for the ESP8266. Sadly, all of the jigs I can find on eBay and other sites have not worked for me. I use the Silicon Labs CP210x, and I have had NO luck at all with that. Normally I use the NodeMCU and it is absolutely great (other than the size.)

My plan is to remove the ESP8266 from the NodeMCU board and then solder pogopins in it's place vertically and mount it in a frame I will build.

The issue is that I have been unable to remove the ESP from the NodeMCU.

A heat gun seems to be heating the board too much before I can get the ESP off, and after it does not work. Adding solder to the ESP pins doesn't work because there are resistors too close to the ESP module and they get pulled off as well. Simply trying to unsolder each pin while lifting the ESP breaks the pads off of the NodeMCU board.

Does anyone have any ideas on how I can do this? If all else fails, I can use the NodeMCU to program another but I will have to pin it so I disable the ESP module is disabled and that isn't exactly optimal.

I have also had very little luck searching google for "desoldering castlated modules."

enter image description here

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    \$\begingroup\$ The CP2102 is a fine chip, whatever problem you are having is probably with your PC or mode sequencing. Having built several Pogo jigs, that is an orders of magnitude harder task. \$\endgroup\$ Apr 9, 2019 at 15:46
  • \$\begingroup\$ BTW, the original NodeMCU also uses CP2102. \$\endgroup\$ Apr 9, 2019 at 16:38
  • \$\begingroup\$ @laptop2d your edited summary substantially and improperly changed the meaning of this question. The asker's question was not about creating a programming jig, it was about desoldering the module. While that's not the question they should have asked (it is entirely unnecessary) , it is the question they did ask. \$\endgroup\$ Apr 9, 2019 at 17:25
  • \$\begingroup\$ Then change it back, nothing is stopping you \$\endgroup\$
    – Voltage Spike
    Apr 9, 2019 at 17:28
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    \$\begingroup\$ you needs about half the stuff on the board to run a bare esp12. if you want smaller, why not a wemos D1mini? \$\endgroup\$
    – dandavis
    Apr 9, 2019 at 19:42

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During prototyping a pcb containing an esp32 I had the need to desolder the esp sometimes. For the reasons you mentioned this is very tricky bit I figured out two strategies that worked well for me:

  1. method: if you have a third hand and a second solder iron, you can bend a massive copper wire to fit the esp's outline so that it has contact to all of the esp's pins. You then apply a huge amount of solder along the wire. This way you are able to melt all solder joints (which works better if you have two strong irons) and finally remove the esp.

  2. method: put the nodemcu into an oven at 250°C (solder probably melts at around 220°C) and wait until the solderjoints melt. Then carefully (!) remove the esp. Of course, all other solder joints will be liquid, so you must not grab the esp by its shielding, neither you should drop the nodemcu! Afterwards wait until the remaining board has cooled down.

I think, in both cases (and also when using hot air) you are out of the specs concerning the solder process (max temperature, max duration), but as you will be using the result for private purposes only and the device will not be running 24-7, this will be acceptable.

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Have a look at the following methods to make programming jig for the ESP.

  • If you really want to go ahead with the de-solder method, try using solder paste and cover all the pins of esp8266 module with it and then use a heat gun for reflow. (this may get a little messy)

  • There are bare NodeMCU boards (i.e. without ESP8266 module pre-soldered) available on sites like eBay & AliExpress.

  • Try searching online this term "esp8266 pogo pin", you will find many videos on YouTube and articles on sites like Instructables & Hackaday.

I myself am working on a programming jig for esp8266 and bought this bare NodeMCU for the same. I got inspiration for the jig from this video.

BTW, it seems like you have already broken quite a few NodeMCU boards.

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Another option I have found to be somewhat effective is:

  1. Add leaded solder to the ESP module castellated pads (it melts at a lower temperature and makes the process easier). More is better, and if you solder bridge that is totally fine. It will make the process quicker as it will stay molten a little longer and allow you to more easily lift the module without tearing pads from the PCB.
  2. Use a 0.001" stainless steel shim to gently lift one side of the module (place it under one corner of the module as you area heating the pin in that corner and it should slip between the castellated pads and the carrier board pads). You may need to move up and down that side of the module to allow enough movement to advance the shim. Focus on moving the shim under the next pad and repeat, sliding the shim further as you go. Solder does not stick well to stainless steel, but eventually you will need another shim once you rub off enough chromium oxide from the shim and the solder starts to stick.
  3. Repeat (1) and (2) on the other side. This is much more challenging for modules that use the bottom row of pads. If you don't care about the module you are desoldering then hot air may be better, although if you have a specific hot air adapter for the module that would be the best option.

I have done a couple dozen brain transplants for former Tuya devices that now think ESPHome. If you rush the process you will tear pads from the PCB, which depending upon the device could be either a whole lot of nothing or absolutely catastrophic.

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