Introduction: Little Trick for Desoldering Through Hole Components

Have you ever felt frustrated trying to desolder a component from a board, wishing you had one more hand?

This trick can help you with some of the components. Specifically through hole components that are mounted with a little clearance below them. By little clearance I mean at least enough room to put a paperclip wire through. And they also should not have their legs remarkably bent on the other side of the board - this method does not work if you need to use force for bending them back. This worked nice for transistors, vertically mounted resistors and diodes and some capacitors depending on their exact mounting position.

Step 1: How to and Video

(Link to the video in case the embed is not working: https://youtu.be/MF6TsMrVT5o )

You need: rubberband and paperclip or semi-hard wire.
Straighten the outer loop of the paperclip and make a smaller hook in the end. Put the rubberband through the smaller loop. Find some way to attach the rubberband's other end to your desk. Put the wire hook under the component you want to remove. Hold the board so that the rubberband exerts a little pulling force on the component. Heat the solder joints and the component will be pulled out as soon as it gets free. The component is very likely to go flying. So be prepared to search for it all over the place. But after a little practice you will learn to pull just reasonably strong not too much and lower the chances of long distance flights.

Step 2: Clumsy Drawing and Disclaimer

Here is also a clumsy drawing of the setup.

It's so simple that I don't 100% except to be the first one to come up with the idea. But I couldn't find a mention of this kind of technique.

Comments

author
mxx (author)2015-04-02

Very nice idea. I would refine it with fred3655's idea of a clip instead of the hook, perhaps a crocodile clip? Then it won't fly away and wait for when you want to unclip it. Of course one can marry your and fred's ideas and modify a pair of helping hands?

author
CurtR (author)mxx2015-04-18

A further refinement would be to determine how much stretch the rubber band needs, the feed it through a plastic tube the length of the band unstretched and attach the paper clip to it. That way the items don't fly all over the place.

author
BeachsideHank (author)2015-04-01

I salvage a lot from boards, far more than I'll ever use but with me it's more an obsession rather than need, this little trick is going to be very helpful. The other method I favor is heating the component's pad and giving the solder a blast of compressed air to move it away from the pad, messy but quite effective, especially on multi- lead components plus the instant chill minimises overheating potential.

author
pfred2 (author)BeachsideHank2015-04-02

If you're salvaging parts and you're using an iron to do it then you're salvaging parts wrong too. Salvage is not rework. So the same techniques do not apply. When I got 2 minicomputers to scrap for parts I had to rethink my game plan myself. I spent over $150 dollars to buy a device called a solder pot. I can put a board over it, and instantly pull up any part I want. 64 lead DIP? No problem! I can pop one of those up about as fast as I can get the board over the pot where it is. You'd be fooling with that all night long using a soldering iron. It'd be beat by the time you were done playing around with it then too.

Good luck trying to blow solder out of a well made through hole plated circuit board too. It's not gonna happen. With rework you're trying to save the board, with salvage you're trying to save parts. So different techniques work best in the different situations. With salvage you don't care what happens to the board, with rework you don't care what happens to the part. These concerns dictate totally different plans of attack too.

author
BeachsideHank (author)pfred22015-04-04

I try and limit myself to the ways and means other people have Fred, a kid in
Chattisgarh India or Addis Ababa, Ethiopia may only have a soldering
iron and pliers as his toolkit while trying to learn electronics, and
little else. The simple tricks like the author posted increases the
chances of a succesful part recovery at no cost, and is easy to
employ. The compressed air technique I mentioned was posted up on
Youtube by a Russian lad, and again is quite effective for what
little he had in the way of resources. $150 for a solder pot =9,228
Rupees, where the mature skilled worker makes only 240 Rupees a day is a distant dream, most surely never to be realized. Their only way
out is through self- education, which is why I posted my small
contribution to the subject, but I do understand your methodology
too.

author
pfred2 (author)BeachsideHank2015-04-05

Yeah you could get a piece of sheet metal, dish it out, throw some lead on it, and put it over a barbeque too. I saw a video on Youtube of a fellow in China doing exactly that. If I'd seen that before I bought my solder pot I might have gone a different route myself. But I bought my solder pot before the Internet really got going. So I went the way I did. Fact is molten bath is the way to fly. Get in on it however you can.

author
BeachsideHank (author)pfred22015-04-05

I also saw a guy using a flat clothes iron to affix SMD's to his p.c.
board, I figured maybe that could work in reverse and mimic a solder pot
so I got an old electric griddle from a thrift store, and sifted some
sand and tried using it as a "hot box", Unfortunately it wouldn't get
hot enough and I didn't want to mess with the thermostat, but one of
these days... I initially used the same technique with a camp stove, sand, and a tray and it did work, freeing up the components, but it was too difficult to regulate the heat to attain detachment but not immolation of the components, so I do think the idea is workable with the right combination of elements.

author
DonO3 (author)BeachsideHank2015-04-05

What's an SMD?

author
BeachsideHank (author)DonO32015-04-05

SMD= slang for "Surface Mount Device":

http://www.globalspec.com/ImageRepository/LearnMor...

author
pfred2 (author)BeachsideHank2015-04-07

SMD is not slang, it is an acronym. An acronym that is completely recognized by industry too. SMT is also a valid acronym, though less used. SMT stands for Surface Mount Technology.

author
arvevans (author)BeachsideHank2015-04-05

It does destroy the PCB but using a propane torch and rapping the hot board on a dishpan usually dislodges most of the components. Do this outside as the smell and smoke is really bad.

author
BeachsideHank (author)arvevans2015-04-05

I did try the torch method, it was difficult for me to get the timing and movements coordinated without suffering too much component loss, and yes, the board is trashed. The most effective methodology would be one that acts like a solder pot, allowing ample time to pluck components without damage, but be of little or no cost- I gotta revisit the sand hot box again someday, I'm pretty sure it'll work.

author
pfred2 (author)BeachsideHank2015-04-05

Forget about dry heat. You want the wetting action of liquid solder to desolder with. Sand is not going to get you that. Liquifying solder efficiently is about more than just heat. Get some heavy gauge sheet metal and bash it into a shallow dish. Then throw some lead on that, and get some heat going under it. Once you got a puddle of molten solder going you take a board held in pliers and just dip it into the top of the puddle, so the bottom of the board is in the puddle. Then quick as you can pick out parts. In a fraction of a second things are loose.

What I do is dip, pull some parts, then set the board aside, so it doesn't get too hot. I generally tend to strip about 5, or so boards at the same time. I can do 5 large, heavily populated boards in about 45 minutes. When I'm done I got a pile of parts then too.

One of the biggest problems today is just finding lead. When I got going I could still get bars at a plumbing supply house. They don't use real lead at all anymore with plumbing. I hear they still use real solder for roofing. Sometimes I find old wheel weights on the side of the road. New wheel weights aren't lead either. I've even melted down old battery plates to get the lead out of them. That's a bit iffy, so I can't recommend it really.

You only need a puddle about as deep as the clipped leads are long on a board. Just so you can get the bottom of the board into the soup. Once you've tried this you'll know I'm right. You'll be like, this is magic!

author
pfred2 (author)arvevans2015-04-05

While torches work they do tend to fry boards really badly, and there is no wetting action going on, so breaking a sweat on the solder with a torch is more difficult too. I generally don't recommend people try to use a torch in salvage, as it is just that much less effective compared to liquid solder.

Plus as BeachsideHank points out below controlling a torch can be tricky.

author
pfred2 (author)BeachsideHank2015-04-05

I don't even waste my time trying to salvage SMD. The industry went to that technology partly to discourage people from getting any use out of their manufactured products beyond obsolescence. They'd rather you just gave them more money.

author
GoatDriverR (author)pfred22015-04-05

pf2, okay, I see what you are saying. Great idea. https://www.youtube.com/watch?v=sHL0a80_oJc

author
pfred2 (author)GoatDriverR2015-04-05

That's it. Connectors are hard. They're easy to melt. He needs bent pliers. Straight ones suck for pulling. With straight pliers your hand ends up on the board. I even find a pick handy for pulling parts. I'll take a picture of my parts pulling pick I use. You're better off standing up doing it too. I wear a leather apron. Molten solder is no joke! I should add that I also hold the board with a pair of Channellock pliers. The gooseneck is better, and it keeps me over the molten solder too.

Anything besides wet pulling is a waste of time. Usually a waste of good parts too. Wet pulling is the safest as far as overheating is concerned. You're just screwing around with stuff for a much shorter period of time. It is heat over time that cooks parts. So speed is essential in the process. Plus you don't want to be spending a dollar's worth of your time harvesting a part worth a nickel. If you're good you can pull about 2 parts a second.

At that rate you're getting around $360 worth of parts an hour. Which is worth doing. I test, and use ICs I've pulled, and they're all good. So I must be doing something right. I've pulled ICs worth $50 a piece. Though when I was pulling them I didn't know. Go price what vintage JRC4558s cost. I found a board with 3 of them on it. You can see one here

https://www.instructables.com/id/GM-Arts-Overdrive-...

It is doing what it was born to do in that project.

PickTool.jpg
author
deltafour (author)pfred22015-04-05

You have me curious.

What's the make of this soldering pot your talking about?

author
pfred2 (author)deltafour2015-04-05

I have an Esico model #37. Here's some pictures of it.

Eisco37.jpgsolderpot.jpg
author
arvevans (author)pfred22015-04-05

Seems that your $150 investment in a large solder-pot sort of negates the economy of salvaging parts.

author
pfred2 (author)arvevans2015-04-05

Yeah well I have a lot of scrap electronics. Including a PDP 11/34. You ever seen the circuit boards in one of those? There's a milk crate of them. When you're faced with salvaging that much stuff you have to bust a move then. I made back what that pot cost me in the first hour I used it.

author
fred3655 (author)2015-04-01

I do the same thing, but I use helping hands (alligator clips attached to a weighted stand). I like the elastic idea, but perhaps you could use a clip of some sort in your design. Thanks for taking the time to contribute!

author
Garetthbutler (author)2016-03-09

Thanks this has solved a long time problem of mine!

author
Mihsin (author)2015-10-29

My third hand is a rubber band.

Thanks.

author
elpayo (author)2015-10-19

Hey, thanks very good idea

author
Leathaldose (author)2015-06-09

I like the hook Idea, cause just some times when my room mate bugs i would like to launch small electronics in his direction.

author
alcion (author)2015-05-04

Muy buena idea thanks from Argentina

author
Mjtrinihobby (author)2015-04-15

old school! i like!

author
mendesjunior made it! (author)2015-04-11

Great ideia!!! The simplest are the best .

2015-04-12 00.47.24.jpg
author
allangee (author)2015-04-09

I use a heat gun. Easiest if I can clamp one corner of the board -- solder facing up. Hold the heat gun in one hand and pluck components from the other side with a gloved hand. Actually, a lot of components fall off on their own. Even DIP IC's are no problem.

author
david.lister.1671 (author)2015-04-09

Why not just use a soldering iron and a de-soldering tool?

My last soldering iron came with a couple of clamps, two soldering irons and a de-soldering tool.

It looks a bit like a spring loaded syringe. Melt solder, place end of syringe next to molten solder and press button. De-soldering tool sucks the molten solder away from the joint.

SIMPLES!

NO melting boards, NO risk of the dog getting shot by a capacitor, NO molten solder being blown around the room!

author
jawtig (author)2015-04-08

Pretty darn clever sir!

Ignore deep pockets Fred over there.

author
laith mohamed (author)2015-04-07

Nice and simple .

author
zappenfusen (author)2015-04-06

Neat idea. I've been using locking surgical tweezers whose name just left my mind. Hemostats! If you have the room to get them between the board and component. Recently acquired Solder wick but I think I need a pump also. Wish I was as good at re-purposing as removing the things!

Zapp

author
dalepowelljr (author)2015-04-06

This technique (and the exact same clumsy drawing) was used by Wile E. Coyote from a little known company called A.C.M.E..

author
teflontony (author)2015-04-06

Large cardboard box, lying on its side. Put the elastick band fixing pin inside, and when the bits go flying, there they are in the box.

author
Rand0mUser (author)2015-04-06

That is genius, someone needs to make an actual tool to do that for you in one package. You could get rich off of that :)

author
suni373 (author)2015-04-05

super idea .....

Thanks.

author
DonO3 (author)2015-04-05

Thanks, I have been struggling with the attempted 3 hand method for decades, you have raised my standard of living!

author
PJSolarz (author)2015-04-05

Solder wick and a good, hot, clean tip on your iron works every time.

author
KurtM3 (author)2015-04-05

Great idea, but careful....you gonna shoot your eye out......:)

author
moonpuppy (author)2015-04-05

Excellent! DH is in the process of working on a &$^%&#^ circuit board and the space is so tight I can't get into give him a hand. This is **SO** going to be put into use! Thank you!

author
Mic100 (author)2015-04-05

I would never have an idea as good thank you

author
tkjtkj (author)2015-04-05

when a thing works,it works ;) good.

author
tkjtkj (author)2015-04-05

Ahhhh HAAA! the "Identified Flying Object" technique !!

yup ..clever , and saves money!! no need to buy those $20 'Third Hand' aligator-clip devices!

Yours should come with an accessory: a large wastepaper basket to catch the devices!...

(padded, of course ... wouldnt want them to be harmed!

I like this kind of simple yet effective idea ...

Good!

author
james.m.smith.7902 (author)2015-04-05

using a parabolic mirror or Fresnel lens on the back of the circuit board you can just pop out the components with a needle nose pliers. I use to have a 14 inch parabolic but a Fresnel lens will work too if you can mount it above you. Don't put it quite at the focus so you get a larger heated area.

author
mtkesari (author)2015-04-05

Brilliant idea !

Have used a custom made rectangular solder pot for DIP ICs - which made pulling out 32 pin DIPs, a breeze - with absolutely no damage to the tracks.

author
bruce-b (author)2015-04-05

Miscellaneous Desoldering Suggestions

Most of the ideas below weren't mine originally, but are ones I've picked up over many decades of soldering and desoldering...

Hemostat vs. Pliers

A hemostat (surgeon's style hemostatic clamp) is best if you can get one, but if not, sometimes, you can make an acceptable substitute by putting a rubber band around the handles of a pair of long nose or needle nose pliers. Some kinds of pliers have handles that work better for this than other kinds. Hemostats are sold that are for electronics (not medical) work. These are likely to be much less expensive than the surgical kind. Often, hemostats are made of stainless steel, which is good for soldering and desoldering work, because the solder does not tend to stick to them.

Desoldering Braid vs. a Solder Sucker

Braid is safer on the board, as a solder sucker can lift the thin copper trace off of the board. Because of this, when I worked in the aerospace industry, desoldering braid was allowed, but not solder suckers. For the same reason, because of the chance of damaging the traces on a board, I use desoldering braid as my preferred desoldering method, and save the solder sucker only as a last resort.

However, all of this probably doesn't matter if you aren't trying to save the board, only salvage the components from the board.

Making Your Own Desoldering Braid

If you can't afford to buy desoldering braid or it's not available where you live, here's how you can make your own from the shield salvaged from shielded (co-axial) cable:

Many electronic items have at least some shielded cable in them. Remove the outer plastic jacket, then remove the shield from the inner plastic insulation. You'll end up with a hollow tube of braided copper wire. Pound or compress the braid until it's reasonably flat.

Commercial braid usually has flux embedded in it, which makes it work better, but your homemade braid will still work o.k., too.

Using Desoldering Braid

Just remember that you need to apply the iron to the BRAID, not to the solder joint. Tin the tip of your soldering iron, heat the connection you're about to desolder with the iron, and add a little solder if needed, until the solder on the connection melts. Once the connection is flowing, remove the iron and let it cool. This process ensures the joint will reflow quickly when you remove the solder; you can vary this step or skip this step altogether to suit the specific joint you're working on. Now, put the braid against the solder joint and then put the iron against the braid, so that the braid is between the joint and the iron. Apply enough pressure with the tip of the iron to hold the braid against the joint. The heat should flow through the braid, then to the joint, and melt the solder. When the solder melts, the braid should absorb much of it. When that happens, remove both the braid and the iron together.

If there's still very much solder on the joint, you might need to repeat this process.

Deliberate Cold Solder Joint

Another trick to desoldering components is to create a deliberate cold solder joint. This works well on multi-lead components like ICs, but this tip also can be used on individual solder joints, as well Normally when soldering, you're trying to AVOID creating a cold solder joint, but when you're desoldering something, deliberately making a cold solder joint can work to your advantage. Here's how to do this:

With the iron, heat one of the component leads you want to desolder. If necessary, add a little more solder to the joint, until the solder in the joint flows. But, try not to add too much solder, because you're trying to desolder, not solder, the joint.

Once the solder in the joint is liquid, grab the component lead or wire with a pair of pliers and wiggle the lead around. While you continue to wiggle the lead, remove the iron. Once the joint has cooled, stop wiggling the lead. As the joint cools, it will form a cold solder joint, and the lead will no longer be adhered to the copper trace on the board.

Repeat this process for each of the leads of the component. Once all of the leads have been loosened this way, you should be able to remove the component from the board.

Hope the above tips are useful to someone!

-bruce-b

author
dentalan (author)2015-04-05

Nice and simple

author
amit_sci (author)2015-04-04

First time ever that this sound track has been appropriate in an electronics video. Rock on!

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Bio: Maker of all trades ... or at least many :) Interested in electronics including programming, woodworking, how to grow edible plants in cold climate of my homeland ... More »
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