Desoldering and soldering SMD components with a minimum of equipment.

okay so I've been seeing some videos lately from YouTube you know friends and so that make videos that I subscribe you know subscribe to their channel and I occasionally see people and even in my videos as well they'll leave a comment about either they're like working on their own radios that's kind of the whole idea behind a lot of videos I do is get out there and actually work on your own your own radios don't be afraid to but one thing I think that scares a lot of people especially with modern radios surface-mount it can be very intimidating to a lot of people they think they need thousands of dollars worth of you know soldering stations and equipment to do it honestly you don't you can heat very little honestly to do the majority of surface-mount work I have several thousand dollar soldering stations because I do this for a living I'm doing it all the time it just helps with productivity cuts down on time it's faster but you really honestly don't need anything but a soldering iron as far as tools go well a pair of tweezers if you want to talk tools but really the soldering iron you don't need hot air you don't need reflow oven you don't need anything super fancy so you know I a lot of times you might use something like this which is a hot air reflow if I'm removing parts I had thermal tweezers I can use got all kinds of fancy tools but honestly you don't need all that equipment the only thing you need as far as desoldering to compare removing the component really all you need is a surface mount removal al aliy now I happen to have one here so they've made my SRA I think yeah sorry this one's called fast chip a lot of people might be familiar with quick chip which is another one different company but quick chip they're all basically US and there's some other companies that make these as you can see it's SMD removal a loli this is not solder whatever you do when we get done using this and I will show you you want to remove all of this stuff because it definitely is not soldered you don't want to be using this stuff to hold components on your board the reason is solder by its nature is usually like this stuff here flexible you sit here and flex it for quite a while you hasn't broken hasn't broken you can just keep bending and bending and it's kind of like a piece of wire it just keeps bending doesn't break it's very flexible this surface mount removal alloy is not this stuff is extremely fragile you can hear that just snaps off doesn't Bend hardly at all it just snaps off that is no good for doing soldering because if you use something like this once you get your part off and you reinstall your new in there's too much of this stuff on there that's what you're going to end up with is brittle solder joints that could very possibly and very likely will fail sooner than later but for removing components this stuff is the bee's knees it's the shiznit whatever you want to call it now the whole key to using this stuff is you want to use a lot of flux now I buy it in tubes you get a lot of it in if you actually there's a lot of it missing out of here I've used it a lot of times I won't even use my high-end equipment a lot of times it's just faster or easier depending on the situation I'm working on where this stuff is actually even easier to use so the whole trick to this stuff is it is an extremely low temperature or has a very very low melting point so if you heat this stuff up with your soldering iron to the temperature that you would normally solder it it stays fluid for a lot longer than solder will because usually when you're familiar with soldering you solder when you pull the soldering iron away you can actually watch the solder it'll change you'll get a you know kind of a smoke to look it'll be nice and shiny and it'll just kind of glaze over that's because the solder has gone from a liquid state to a solid this stuff does not act like that it will stay a liquid for a very long time relatively speaking but for a long time which the whole idea is it allows you time to remove components so it allows you to flood all you all the sides of whatever component you're trying to remove with this desoldering alloy and then you can just come in with a pair of tweezers pick the part up off the board while all of that sawed you no more soldering on you pull the soldering iron away it'll still be molten you can come in with your tweezers take the part up off and remove it now again the whole key to anything you do when you're doing surface mount actually the first thing is is practice so this is not actually a circuit this is a practice board and you can see it's some yeah I don't read Chinese so I have no idea what that says I actually got clubs doing some soldering videos in the past I had planned at some point in time on doing surface mount ones that I kind of got spurred to do this one because like I say some of the videos I've been seeing recently people saying about their intimidated about doing surface mount you can buy these kits on eBay you come in a little bag they're cheap as dirt and they're cheap I mean really cheap boards but you get this comes with all the components that you know it comes with a part for every single location so it comes with ICS you know comes with everything you need comes with transistors and some diodes and resistors networks comes with everything you need to fill in every hole but they're great for practicing and honestly if you can solder one of these things trust me you can solder anything because these are about the lowest quality cheap pieces of junk circuit boards you're ever going to see in your entire life you really need to burnish these boards before you try to solder them now this one I actually alright started to just just I wanted to brighten up some of it but if I come in here with my own fiberglass brush at the angle just right you can see how it's really shiny here here and right here well that's what I just burnished everything else on this boards dark yeah if you try to take those parts over there and stick plop them on this board and solder them it ain't going to happen guys and gals solder just will not stick to these boards until you clean and they're just really honestly crap quality so a little bit of clean they work fine for practicing oh but if you can solder one of these you should have no problem d soldering and soldering components on your you know in your radio or television or whatever you haven't happen to be tinkering with so what I want to show is how do you remove let's say we want to replace that I see right there so let's say this is a real circuit this boards out of a radio we've diagnosed that IC is bad we need to replace it but we don't have the proper hot-air reflow tool or we don't have the proper tweezers with the proper tips to remove this where we're going to use this we even have a new IC right there to put in it so the whole key to doing anything soldering or desoldering when it comes to the surface mount is flux flux flux I will say that again flux flux flux flux and cleaning are the two most important things you can do to have a successful be soldering and soldering experience when you're dealing with surface mount flux as a cleaning agent as you heat it up actually kind of guess you could say it becomes slightly corrosive or mildly corrosive but what it does is it it's slightly etches the traces helps to clean them up but it also helps to break the bond so there's kind of a wetting action there and if you've ever taken a soldering iron you try to pull you know you solder something you try to pull your side if you've been on there for a while and all the flux that's inside of you a normal solder like this has burned up you'll notice that when you go to pull your soldering iron away the solder doesn't just immediately break off it'll kind of be stuck to the end and still stuck down to the part and you're left with a little little new pointy part that comes out it doesn't just ball up and wick right back in where if you touch a little bit of flux to it and try that again as soon as you go to pull the iron away it cleanly breaks and you'll have a nice shiny solder joint flux helps with that wetting action and the flow out of the solder so we want a lot of flux and more is better than not enough because flux is easy to clean off so if we get too much on this board ain't gonna hurt nothing we can just clean that off with some IPA or isopropyl alcohol later which we will do so I fled that whole thing with lots of flux now as far as flux goes you can use gel fluxes this is what King Bo RMA 218 flux okay so this is a gel flux will get squeezed out here okay so that's a gel flux that works fine I've actually kind of gotten away from the gel fluxes directly in my opinion can be a little bit messy sometimes or you can use liquid fluxes now I make my own and I buy premade so this one is homemade it's just pure rosin cake I buy hard highly refined rising cakes chip up the tip that up put it into a bottle and dissolve it with 99.9 percent IPA and I also buy it now I like this this is made by circuit works its composition CW 30 to 20 we have written on the bottle there now the only downfall with that flux is I think the smallest container that they circuit work sells this stuff in is like a gallon bottle might be a half gallon but I think it's a gallon jug as the smallest quantity they sell that's more flux than I will use in 10 years but luckily thanks to eBay there's a guy on eBay that repackages it actually even has a website dick dickie da Dickies garage sale calm but I just get it on eBay and bottle like this lasts me about a year so actually it's about time for me to order a new one I just use this model to refill my little nail polish bottle there but yeah circuit works CWA 3220 really good slugs so we've flooded the area with that we're going to take our soldering iron to make sure it's turned on and we just want to flood see how fast and easy that stuff melts flood both sides of the component and you can see perched just bouncing around and now I'm going to pull the soldering iron away still have plenty of time you see there still pull it off but stuff still molten it's what I say has a very very low melting point so we got a blob on there that we need to get rid of now because we need to put a part back down here so we want to remove all that if you don't have the soldering irons you really again you don't need anything fancy just plain old desoldering braid works just fine actually it's it's actually really good for cleaning up the traces later because we want to make sure we get all of this stuff off of the board we don't want I have a lot of this alloy left exactly the last thing you really want to happen there's some wire cutters here and another thing to have handy you may not have seen at a camera view when you're doing stuff like this now you don't need a fancy little surface mount you know station like this this holds some cleaning brushes and sponges and has this nice little thing to drop hot parts onto and to clean off tips and whatnot you don't need anything fancy like that but before you do something like this removing parts before you pull the hot part off make sure you have somewhere to lay it so even a piece of cardboard or a piece of paper folded up a couple of times but somewhere where once you've got the part off the board you can pick it up you have somewhere to drop it you don't have to sit there and hold it until it pulls down but so anyhow we want to make sure we get all this goopy stuff cleaned off of here like I say kimwipe actually works really good for this okay now I've got most of the cleaned off but I can't really see because there's just so much flux residue and goop on a so I have brown stuff you really can't see what the hell you're doing that's it again where it comes in clean clean clean so I'll just grab a chem wipe isopropyl alcohol it's going to wipe this down so I can actually see what I'm doing because it's kind of hard to work on stuff if you can't see what the heck you're doing now I want to come in here make sure I get those pads as clean as I can you're never going to get all of that alloy off of the board actually it's back in camera view there you're never going to get all of that alloy off of the board but you do want to try and get as much of that alloy off of the board as you can I'm just going to run back and forth across those pads a couple times make sure I've sucked off as much as I can with desoldering braid now you don't want to hold it on there for an extremely long time actually I've used this one so many times and demonstrations you can actually see there's one pad which actually isn't a solder pad it's actually meant like as a test point I guess but you can see that's actually been lifted off again this is a really cheap board but you don't want to leave your soldering iron on here for a really long time you have to remember it's a fiberglass circuit board with epoxy the epoxy actually starts to decompose at the temperature lower than your soldering energy is set to so if you leave a soldering iron on here too long you the epoxy actually starts to decompose and what happens is the circuit traces will come loose now you're going to have pads to try to repair possible circuit traces so you don't want to have to go through all that so always when you're designing and doing stuff like that always try to keep moving you don't want to keep concentrated heat in one spot for an extremely long time because you do stand a chance of damage especially when you're using something like desoldering braid because you're dragging that across when you're cleaning the pads if you leave this set it there like that and just wait and wait and wait and then go to drag it across you can rip that trace off so now we've got that cleaned off pretty good we want to again come in grab a new one a bit IPA clean the board off really well nice and shiny pads now we want to get our new part out now there's several ways you could solder this course if you have hot air you can use like I have you could use hot air to do it stuff like this I see I prefer to do what they call drag soldering which is what I'm going to demonstrate now you can also do point by point so you can solder each one of these pins one at a time not me I have work to do and don't have time for every time I have to replace the surface mount component I don't have time to be hand soldering each individual pin I need to do this with some type of speed so I do drag soldering that's where it comes in handy buying these practice boards stuff like this because now you have somewhere to practice your drag soldering skills you know you can go in try it perfect your method but the whole idea behind drag soldering is it's just what it says you're going to drag your soldering iron tip actually across there and you're going to be sunk you're going to solder all depends on one side and you're going to come across and just wipe the iron across but all of your solder is going to need to be on your soldering iron tip before you start but before we do that again just like with desoldering I get this thing about halfway position they're out there we want to again flood the area with flux flux flux flux this is probably even more important having lots of flux here now than it was when we were doing the removal you want lots of flux here especially sin we're doing drag soldering now this is going to be a little tricky the camera is always into my way trying to get it positioned it's not too much in my way I can still get in here and work so you want to try and get your part positioned try and get it centered fairly well on the pads and centered left to right now it doesn't need to be 100% perfect if it's a little bit cockeyed or crooked it's not going to kill it quite honestly yes it's not perfectly straight but honestly as long as you have good contact with the pads and the leads and you don't have shorts between any of the pins if it's a tiny bit crooked it's not going to kill it people some people make this harder than it needs to be I think that's another problem people have so now I'm going to be doing drag soldering so I can just use some big fat chunky solder here because we're not going to be applying the solder down onto the board like that we're going to just be using the soldering iron to do that so now we just use this with that out way so what I want to do is I want to apply some solder to this thing and I want to clean it a few times so I'm pinning this tip wiping it off we're going to repin it again I want to try to get as much of that alloy off of the soldering iron now ideally in a perfect world you should probably have a dedicated tip but honestly if you just retain your tip about three times you will have if there's any of that residue left on your tip it's such a microscopic amount that it's not going to honestly make a difference so now that your tips all nice and clean what you want to do is just come in and put a little bit on here because what we want to do is the first thing we need to do is tack down two corners so the IC can't move around so and I got to try and do this around the camera I'm going to hold the IC down moved on me of course look around the camera here there's one corner tact remember flux flux flux never have too much flux there's any doubts just add some order okay now both corners are well tacked down I can see the ICS not moving around if I try to pull it off so that corner and this corner down here are well tacked again I just want to make sure I really flood area flux I know a lot of you're probably thing is too much flux I guess a no thing such thing as too much you can always remove the excess but it's a lot easier to remove excess flux than it is to try to fix bodged solder joints or bridges because that's what you'll end up with you end up with solder bridges if you try to drag solder and you don't have a sufficient amount of flux on there so all we're going to do is take our soldering iron we just cleaned it and clean there's still a little hickey on there or something so clean the tip and we want to put a little ball of solder on here don't need a heaping you know keep in helping just a little little ball of solder and what I'm going to do is is just as the term said I drag it across apply another little bit of solder perfect ended up with a solder bridge actually was hoping I get one of those I want to demonstrate how you remove a solder bridge I've got one solder bridge so a solder bridge is when you bridge between two pins and you can see the two on the left hand side there you see that shiny spot in the middle soldering iron back in the tree there that's and tweezers but there's a solder bridge right there okay normally I wouldn't end up with those like I say I'm trying I can't can't see what I'm doing because I'm working around a camera there's a few methods of getting rid of those things the first thing I normally do is again I'll apply some fresh flux because the flux that's on there has now been used because we just got done soldering okay so you want to apply a little bit of fresh flux clean your iron off really good and just come in and a lot of times if you clean the iron off there's really no solder on the tip now you can just come in just like that and it's gone okay you when what you've done is the solder that was on there because there was an excess of solder there was hardly any solder on the soldering iron tip and a lot of flux when we touched the soldering iron to it the solder was drawn up to the iron now if you can't get it off that way because usually actually that's actually the knot where you'd find a solder bridge usually what happens is when you drag your soldering iron across if you're going across these pins like this a lot of times where you'll end up is these last two pins so you'll drag the soldering iron across you'll end up with the bridge at the last two pins because as you come down you go to lift your iron off the solder will kind of blob and break and it flow back over to the second pin there so that's usually where it'll end up with it's easy to get rid of like I say you can do it the way I did just add some new flux clean your tip off bring that basically a dry iron tip in and the solder will be drawn up to the tip or you can just use some desoldering braid now you don't want to remove all the solder because remember that's the whole idea is here we're making a solder connection but what you can do is actually I'll use these unsoldered pads as a good example so let's say there was a component one here okay we'll use this tweezer as an example a little bit oversized but it's great for demonstrations because you can actually see so you know the lead would be spaced about like that they're usually still be some exposed pad out here what you can do is bring the desoldering braid in don't lay it on top of the lead like this you know on this IC you don't want desoldering braid to touch the IC you want to just barely bring it in just to touch the end or the toe of these leads I like to right here you're just touching the outside edge of that pad or the toe of the IC then touch it with your soldering iron and you'll actually see that solder bridge will get drawn out because you've got to remember they call this desoldering wick or you can wick is actually a brain that's actually with this is that's why it's a wick and it's actually exactly what it does if you have a solder bridge here you'll actually see it with that solder out but you don't want to draw it all up it's got to remember that's what we're doing we're soldering we don't want to remove it all so now we've got that all - want to clean that off really good so we'll get somebody put the camera back up that my way a little bit here with IPA in here it was a nasty ones fresh one dry off air a little bit and we can see get the camera to focus because pocus focus sees nice solder joints no bridges the one bridge we hit did have there we easily pulled off with what I call the dry iron technique so you know add more flux come in with a dry iron and a solder will be drawn to it but like I say don't make it any more difficult than you need to you don't need fancy tools a little bit of this alloy the whole trick to using the alloy to get really good flow out of that stuff flux and the whole key to getting a good solder connection and preventing solder bridges growing off solder bridges again flux that's the whole key and I think that's probably one of the big stumbling blocks for a lot of people when they try to do surface mount work they're not using they're either not using flux at all or they're not using enough of it more is better again I've actually gotten to the point where I prefer the liquid flux over the gel fluxes the gel flux is when you apply them for starters it's a gel when it's kind of opaque it's kind of hard to see through this stuff it's it'll in my opinion a little bit easier to clean up it's already dissolved in alcohol that's what's in this model the flux dissolved in IPA so full been in my opinion a little bit easier to remove it's also more transparent so easier to see what you're doing but there's just a really quick demonstration of really the only thing you need two lies soldering iron pair of tweezers helps to pick up the part unless you've got some new ceramic coated fingertips but yeah pair of tweezers and a soldering iron as far as tools go that's really all you need doesn't need to be a fancy soldering iron just a little pencil iron this new this one is a pace so it goes down to a big soldering station but it can just be a standalone plug in the wall soldering iron the removal alloys now I'm not sure about SRA but I do know a quick chip they sell little small packs because honestly if you're just a hobbyist you're not going to need this much a tube of this stuff lasts me a long time so you know for a hobbyist this is a lifetime times 10 supply probably but I think the quick chip they have like don't like one of these lengths in a ziplock bag just one length with a little bit of their flocks it's cheap doesn't cost much and for the average user that's probably enough to do several repairs you know several stuff like ICS or stuff because you saw it didn't take an excessive amount you just need to flood each flood you know all the leads and then pull the part off so I hope that helps like I said I want to try and do this just live one continuous shot no editing so everybody can see you know how easy it is it's not hard I think the biggest biggest thing is it's just people think it's hard or they think it's harder than it actually is get yourself some cheap boards like I say they sell these kits on eBay you can't beat the price I mean ship from China honestly I don't remember five seven dollars so it could have been cheaper net could have been two or three dollars for all I know it's been a while but you get a couple of kits like I say the whole kit the whole trick to using these is these boards are tarnished at least the ones that I got were so make sure you clean them off first you burnish the copper traces there because you're never going to get solder to stick to these things once you once you burnish the boards you know take like a fiberglass brush once you clean them up you just trying it in the camera just right you can see there's I'm never going to find that perfect angle again mi trying to get the reflection just right you can see yeah you can just yeah you can see like there those ones I just went across there a lot shinier than the others so yeah you really want to you know clean all of these traces up before you use this board if you have one of these little cheapy fiberglass brushes again eBay is a great place for getting these little fiberglass cleanup brushes you probably order them from the same company that sells these boards fro on no that's not these companies sell similar products but just grow over it like that clean it up really good makes a great demonstration practice makes perfect so there you go I hope some of those tips help somebody's that main thing to remember removing surface mount components without special tools desoldering alloy and no matter what you're doing what type of you removal anything you do with surface mount cleanliness so in between each stage you want to clean clean clean but probably the most important thing is flux flux flux I just can't overstate to add enough flux flux flux lots of flux prevents lots of problems

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Id: _g8mvs482Ng

Length: 31min 13sec (1873 seconds)

Published: Sun Jul 16 2017