Desoldering Doesn’t Necessarily Suck

What’s your favorite way to fix soldering mistakes or get usable components off that board you found in a Dumpster? I’ve always been partial to desoldering braid, though I’ve started to come around on the vacuum pump depending on the situation. [Proto G] sent in an Instructable that outlines nine different ways to desolder components that take varying amounts of time and skill.

He starts with one that is often overlooked if you don’t have a solder pot. [Proto G] recommends this method only when you don’t want to keep the board. Cover the solder joints of the components you want to keep with flux and hold it over the solder pot while pulling out the components with pliers. The flux isn’t critical, but it makes removal faster and easier.

For boards in need of repair, [Proto G] uses a manual pump or copper desoldering braid that comes coated with flux. If you can afford one, a desoldering machine seems like the way to go—it combines the heat of a soldering iron with the vacuum of a manual pump. Desoldering tweezers and hot air rework stations look like great ways to remove surface mount components.

If you enjoyed this, check out [Bil Herd’s] guide on component desoldering. There are also few ways that [Proto G] doesn’t mention, like holding the board over an alcohol flame. Let us know your favorite desoldering method in the comments.

42 thoughts on “Desoldering Doesn’t Necessarily Suck

  1. Pace SMC rework station if yiou have a good selection of tips. They are among the best to remove IC chips either surface mount or conventional. Those used various tips that fit around the component to easily remove them,
    The only problem with vacuum is that while it removes 90 percent you will need to still pry and wiggle just after removing the tip to get the component lead to become loose in the hole. There is another product we used to use called ChipKwik. Basically it is a low temperature solder, so you could apply it to all the pins, then heat it up and it would desolder all of them and allow easy removal. SMC chips would actually float right off the board. Cleanup used a special paste that cleaned all the rosin and use braid to remove excess away leaving bright shiny traces ready to resolder. No damage to the foils.

      1. Yup, it’s ChipQuik or nothing for me – without it even with hot air I’m just scorching the PCB heating one side at a time of a TQFP while the other three cool back down and just hold on for dear life until it all simply delaminates and/or chars. There’s just no comparison…

          1. If you mean a nozzle that blows hot air on all four sides of the chip at the same time, then no… but then again, I sure have a lot more chip sizes to desolder than 4-sided nozzles, and I can never find one that would seem to fit… ;)

  2. Use big blobs of solder to keep several pins hot, moving the iron quickly from one to the other. Good for SOIC8, for instance.

    Use a hot plate for single sided SMD boards.

    Remove connectors (destructively) by pulling the pins out one by one.

    1. I use a similar method and piece of AWG#12 solid wire cut to the width of the chip. I have even make a square piece of wire to go around small PLCC packages for desoldering them.

      These days, I use a hot air rework tool for removing localized parts and toaster oven is a good way to remove entire board of SMT parts.

  3. Hot air gun(paint stripper/heatshrink type, something with a big of power), blow on the back of the board, then hit the board on the bench and sort out the parts you want from the stack.
    Or set the gun pointing up and just hold the board over it as you pull out the bits.
    Tends to wreck the board and melt connectors, but it’s great for mass-desoldering.

    1. I used to wave a medium flame propane torch on the back of the board, then smash it over the edge of my box trailer tailgate. Components would fly everywhere and there would be a “bit” of a smell.
      Needless to say this was done outdoors. Sometimes the components would be hard to find on the driveway afterwards, however it was certainly a MASS desoldering technique.

  4. I use different method. I don’t know how to explain it well.
    Basically I clamp the board in wise, pull the board (bend with board resistance) and melt the solder. The I release the board and shoot the solder out the holes. :)
    Sounds funny. Bu my wall if full of solder shots.

  5. For rework I have a Metcal solder sucker gun for through hole stuff and got the heated tweezers for SMT stuff. Really nice but kind of expensive even used. Also the solder sucker needs shop air to work, I use a Jun-air compressor under the bench. It is very quiet, sounds like a refrigerator running.

    For mass desoldering I have used a solder fountain. Think a giant solder pot with a pump that pumps the solder up a large tube in the center. Works very well for through hole stuff. I have also used torches, propane and oxy-acet. Has some vicor power modules I needed to remove from some really thick (.125″) pcbs. The pins were all in a row so I used a 00 tip on the torch with the flame parallel to the board and managed to just heat the pins and pull the modules off.

  6. I like my foot bellows, it hangs from above the base so stepping on the lower half creates a good suction. A flap valve on the top makes it exhaust fast. Easy to repeat, it’s not like using a muzzle loader. I modded a plunger type iron so the solder stays in the chamber and a perforated tube (filter) goes into the end inside with an elbow nipple epoxied into the button trigger hole. Solder doesn’t get to the hose or bellows.
    Do be careful about splatters and bits, tracking (shoes) such about your abode is not good.
    Lead!
    It turns adults in to children and children into XXXX.

  7. Honestly buy a rework station on ebay and make your life easy. Why a lot of guys fight with makeshift tools I’ll never understand.
    I bought a china rework station for $69.99 and it’s great, I love the surplus hot air rework that only needed a small repair to get working again. Buy the right tools and make everything easier.

    1. I once got a cheap Chinese rework station. After one afternoon working with lead-free solder, half the tip was gone. Also, the damn thing required cleaning every 15 minutes or so. Complete waste of money.

  8. I’ve used most of the techniques mentioned already. This one is a variant of heating the entire board. I have a wood stove in my garage that works great for that approach. The other I use that is not mentioned is using core drills. When removing parts with several large leads in thick boards I find a core drill for freeing the part is usually faster and less messy than other approaches. When the part is separated from the board the remaining pads can be easily removed from the pins with a soldering iron.

  9. I’ve used a lot of these methods. The method I do if I don’t need the board is a gravity method I saw in a YT video. You heat a pin on the component and then drop the board from about 1-2inches, gravity will throw the solder out before it has time to solidify. Rinse and repeat.

    Works quick which is why I like it.

  10. Guess i’m pretty lucky working at a medium sized company in the electronics department. I have access to basically all the fancy tools you can imagine: Temperature regulated pen-type hotair stations, with special dspersion and shielding adapters for different footprints and spring loaded vacuum-suckers that lift the IC’s from the board as soon as the solder is liquid enough. Of course the good old weller rework station that is just perfect to unsolder any THT components (the solder-iron that has vacuum-pump included to suck up the solder thru the iron-tip). Then there are the soldering tweezers for quick passive smd component rework, the little reflow oven, board preheating plate and our newest addition is an ERSA HR100 IR rework station. Pretty nice piece of technology, very precise to only heat up the component or part of the board you want to rework. Of course there is the normal solder irons in all shapes and sizes and hand vacuum pumps, wicks and all the standard hand tools and the different magnification glasses and binocular microscopes to actually see what is going on with the sub-millimeter parts and pitch sizes.
    To me it is still fascinating how people with limited access to the “right” tools come up with creative solutions to do most of that stuff with way less investment in hardware. On the other hand, in a professional lab you probably are more interested in doing all the work as fast as possible and according to IPC standards, especially if you do stuff that ends up in a system intended for customers and that system should run reliably for the next few decades.

  11. I habitually scoop electronic stuff off of curbs or recycling piles and take’em to bits. Besides cool subassemblies like stepper motors, most of the stuff I want to save is thru-hole. Small discrete stuff I will use an iron and a Solder-Sucker, and maybe some braid. I have one of those irons with the vac bulb, but the tip rots out too fast.

    I rarely save soldered DIP ICs, but will sometimes take a small butane torch to the backside of the board while pulling or prying on the IC. I rarely save surface-mount componemts, but have been able to service some by removing an IC using #30 solid wire under the pins.

  12. Hot air gun (for stripping paint etc) is your best friend you can ever imagine. It is much more powerful than the standard hot air tools yet not as destructive as a propane torch.

    I was using hot air station for years but eventually dumped it in favour of a simple tool taken from a hardware store. The trick is the reduction nozzle. It doesn’t only need to be thin enough for precise work, it also needs to have a “bypass” which lets part of the air out directing it elsewhere than on the PCB. This will somehow prevent blowing off innocent parts from the board (although not being careful this can still happen).

    Some years ago my colleague working for a phone repair company said he’s using it for virtually anything and i couldn’t believe but yes, once you get to know the drill there’s almost nothing you can’t do with that crude, as it may seem, tool.

    I work a lot with automotive electronics which happen to have a lot of QFP64-QFP128 or similarly sized parts. Removing
    a Freescale ST12 out of the board for programming takes mere seconds when you know how to do it. Replacing it is just a matter of good tweezers, steady hand and lots of quality flux (i am using RMA7 from Cookson).

    Another problem for me was power parts (power switches, MOSFETs) that usually come in a D2Pak kind housing and use the PCB as a radiator. They were almost impossible to remove with hot air tool because the surface (and thermally connected parts of the outer metal housing) are so efficient in removing the heat that you just can’t get the solder past the melting point. With air gun i am able to remove these in matter of seconds – however preheating the whole board a bit doesn’t hurt so for example you do not break loose the pads of a nearby BGA.

    Cheap Steinel HL-1400 is my best friend, it has two stages of heating (2nd one is rather for mass desoldering or mass destruction if you choose so – keeping it over same spot of PCB will quickly fill the air with famous phenolic aroma and the traces will start to bulge). I have also tried more expensive models with continuous adjustment of temperature but this doesn’t really add to the process so no need to buy the expensive one.

    As always with powerful tools, you need to take plenty time to practice – desoldering stuff is a first stage for getting acquainted with this powerful method, then try to solder back some of the chips, then try to desolder something in a “selective” manner so you don’t disturb the nearby components. I will never go back to a hot air station again.

    1. +1
      I work with a Steinel HL1500 maybe for 7 years now, its the best option to remove parts bigger than SO16. To prevent collateral damage to other parts i cover the components around the suspect with aluminium foil. I have several pices of foil with pre-cut holes which fit different package sizes.

  13. One through-hole clearing technique I’ve used for 20 years is a tiny drill.

    The typical heat/wick/suck cycle often fails in small holes – say, .025 or .030, and multiple attempts will often screw up the hole.

    I keep a couple of those small hand chucks that you find at hobby stores pre-loaded with tiny drill bits on the bench. When I’ve gotten all the “easy” solder out of the hole, I just drill out what’s left. Solder is very soft, and it’s very easy to control the material removal. Centering the hole is easy because the surface usually has a good “divot” from the wicking/sucking operation.

    The only thing you have to be careful about is that you use the smallest drill you can get away with, because you don’t want to drill out the plated-through “barrel” that goes through the hole.

    The chuck I use is made by a company called “Commando Products” (http://www.commandoproducts.com or amazon). You can get a chuck complete with a set of bits for $15. The tiny bits are easy to break, you can get replacements from McMaster for $10/ pack of 10

  14. I had to de-solder, and re-position a QFP44 earlier today not having any fancy tools, or any braid on hand, I heated it with used a small propane torch and once loosesend flicked it off with a screwdriver.

    1. Contrary to what people think, PCBs and chips are quite resistant to high temperature. Forensic part of my job involves recovering EEPROM data from burned cars; even if the module is a total toast, most of the time i am able to recover the memory chip, clamp it in a programmer and presto! data comes my way. Removing the chips with propane torch will work unless there are sensitive components nearby ie. lytic caps or tiny plastic parts – i have to take extra care when removing MCUs from electronic ignition switches as they are built entirely from plastic and tend to seize after overheating them.

  15. im cringe-worthy when it comes to recycling thru-hole parts off of garbage boards.

    i try springloaded sucker, if that fails and im only intending to do DIY work, i get nasty.

    getting nasty: cut the board around the component, then CAREFULLY cut between the pins, then gently liberate the remaining square of board with fingers or needle-nose pliers.

    if im in a bad mood and its REALLY only for learning and not even DIY then i might take a worse approach, … i might just cut the component off and solder extension pins onto the remaining length of metal for breadboard use, if i later decide to solder it to a board, it gets dicey because the solder attaching the extension/repair pins melts when you go to heat it for soldering to the board!

    PS: extra length on chips can cause electrical problems …

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