SMD Soldering Tutorial | Guide | Tools | Tecniques | Stencil

pretty much all of my pcbs designs have smd components standing for surface mounted device and basically all electronics nowadays will use this type of components i think it's a good idea to learn how to solder these components what tools we need what techniques we have and which are the most common smd components that you could use with everyday projects so let me tell you how i solder my smd components and maybe you'll learn something new i would like to say before i start that i'm not an expert but over the last years i've practiced a lot so guys let's get started [Music] video sponsored by glc pcb consider using their main service for pcp manufacturer for only two dollars for five pcbs of any color together with that you can also order the stencil for using solder paste this is made out of stainless steel and could last for thousands of pcbs in this way you can solo your components easily and create perfect prototype pcbs the order process is so simple just upload the gerbers to jcpcb.com select the pcb settings mark that you also want the stencil and place the order in a few days you'll receive the products what's up my friends welcome back to make this entire video i've designed a pcb that will have all kind of smd components so we could practice this video will go by difficult level and component complexity you will learn how to solder 2 pins component sizes of 1206 zero eight zero five zero six zero three and even small ones of zero four zero two this will include resistors capacitors diodes and leds we could then pass through some three pins components such as some voltage regulators or some sot-23 mosfets you will also learn how to solder sop packages in this case we have panes on both sides and i've prepared an ic with 8 pins and another one with 16 pins finally we can go and solder some dqfp formats such as this microcontroller we will also see some smd electrolytic capacitors which are not that easy to solder at first some smd inductors some micro usb connectors and more i will also try to show you different techniques the mandatory tools that we need some types of soldering tips that we have how to use the solder paste and the amazing flux how to use the hot air gun and so on so let's start first let's see the tools that you must have in order to achieve good results of course that we need a soldering station the higher the quality the better if it also has a hot air gun even better one important factor is the ability to set the desired temperature but also to be able to change the tip shape for example this type of soldering irons are not that good because they always go to their maximum temperature which is usually 500 degrees and we can't easily change the tip neither so i recommend you a soldering station or maybe this kind of digital portable soldering irons with temperature control the most common ones are the ts80 and the ts100 but you also have some very low cost based on the t12 tips and these are also pretty good anyway next we need some solder so try having the best quality possible also for smd the thinner the better in my case i usually have a 0.81 but it would be much better to have a 0.5 millimeters one or less in case that you use a hot air gun you will need some solder paste you can get this in this plastic syringe like this one or in a small plastic cup also check that you have a good quality paste that is not expired and also make sure that you store it at low temperatures next we need flux this is a special paste or a chemical cleaning agent this will help the soldering process we'll keep the pads clean and with no oxide and also make sure that the solder will stick only to the metal pins and the pads and not join the pads together i recommend you to buy this type of creamy flux it comes in a plastic syringe so it's easy to dispense for a few more dollars you can also order a metal dispenser like this one that will help you pour the correct amount we also need cleaning alcohol isopropanol is a good choice it cleans very well and evaporates very fast for a few dollars you can get one liter of alcohol but if you don't have that you can also use acetone but is not that recommended together with the alcohol you should also buy some cotton swabs we use this to clean the area the excess of flux and solar debris you will see that sometimes while cleaning this will fill the board with tiny cotton hairs so that's why together with this you will also need a small brush like this one and sometimes we also need a stronger brush such as a toothbrush so you could have this as well they are quite cheap i recommend you to also use gloves and maybe even a filter mask just in case a fume extractor would be the best choice now very important we also need some very thin tweezers for the small components there are a few shapes that you could find i also recommend you to pay a little bit more for some better quality for example for only two dollars i bought this kit but just in a few months they got damaged they bent very easy and so on so for nine dollars i bought this other one which is made of a stronger alloy and has a very thinner tip better grip and easier to use in case that we need to remove solder also make sure that you have some desoldering copper braid this help us to remove the solar excess or completely clean the solder from the for this solder process it would be nice to have a magnifying lens and a good pcb support a better solution is to use a digital microscope like this one i recently bought this device for reasonable price and i really recommend it because it has full hd resolution sd card and an hdmi output nice light and metal support and is very easy to focus and use so please comment below if you would like to see a full review of this microscope together with this microscope you could also have a metal base the one that i have has magnetic legs which are very useful and also very easy to place the pcb in the position that you want i'll put some links to everything that you see here below in the description so in case that you want the same microscope or the soldering tools check the links below as for the tips which are very important i recommend you to have various shapes in my case i'm using the 900 md model which is quite common as for the size the one that i most recommend you to have is at least the 1.2 d but you should also have the i model which is curved and the c model which has a flat tip in my case i'm using the 2c size we start with very easy to solder components and that will be the 1206 capacitor and that will stand for longitude of 0.12 inch and the width of 0.06 inch or if you are using the metric system 3.2 by 1.6 millimeter so clean the surface of the pcb with some alcohol just to make sure then fix the pcb in place so it won't move around and ruin the entire process so for a two pin component this is what we do with the 1.2 d tip we hit one of the pads and then we add some solder then take the component with the tweezers and place it close to the pad touching the pcb heat again the solder till it melts and slide the component into the melted solder till it touches the tip of the soldering iron and then first remove the soldering iron wait for 2 seconds and then you can remove the tweezers at this point if the component is not perfectly aligned you could reheat the solder and change the position but have in mind that if you hit the solder more times the more you do that the more it will lose the properties and get dry and not shiny now we go to the other side using again the 1.2 d tip we preheat the other pad and then carefully add a little bit of solder if it loses the properties due to too much heating just add a little bit of flux then carefully heat once again the pad the solder will now gain back its shiny color a good solder can be seen if you have a curved shape like this one between the pad and the component you will see that the soldering process and the flux will leave the area quite dirty so finally using a cotton swab and some alcohol you can clean the area and you can also use the dry side of the cotton swab to remove the alcohol excess sometimes this process will leave some cotton filaments so using the brush you can remove that as well and there we have our first component soldered let me tell you some mistakes that you could make you can add the solder before you hit the pad that will make the solder stick to the soldering iron tip but not to the pad this will not be recommended even if the solder will finally stick to the pad as well if you want it to stick directly to the pad just make sure that you hit that first you could also add too much solder this process will create a ball of solder at the end of the component this doesn't look good and is not recommended you should add some flux and then use the copper braid to remove the excess then add a little bit more flux and repair the solder point okay so the next component of two pins is a smaller size of 0805 this process is exactly the same but being a little bit more careful and using less solder in this case we have a diode so check the polarity mark on the silk layer of the pcb then we do the same we heat the pad and we add some solder then we place the diode flat on the side we heat back the pad and then we slide the diode into the melted solder then we go to the other side and fill the other pad soldering very small resistors or capacitors is a bit more tricky using the soldering iron so in this case i change my tip to a 0.8 d model we add solder to one pad and do the same process once again but in this case it's quite probable that you will add too much solder what i recommend is to add a lot of flux and then hit once again each side and the flux will make sure that only a certain amount of solder will stick to the component but even so it's quite difficult to get a perfect solder using these small components okay now let's pass through some three-piece components we start with this regulator in sod format in this case you have to select a pad to start with and the method is using a fine soldering tip in my case i use the 0.8 b model so only hit that pad and add a little bit of solder as before now take the component with the tweezers in such a way that it will be easy to align it with the pads on the pcb put the component close to the pads and hit again the solder slide the component and make sure it's in line with all the pads now remove the soldering iron wait a little bit and remove the tweezers now check if the component is flat on the pcb and in line with all the pads so now you can hit one by one the other pads and add some solder clean the area with some alcohol and remove all the small filaments with the brush the same process will be in case of an sot-23 mosfet first one pin we slide the component in line with all the pads let the pin to cool and solder the other two pins all this takes some more time to heat up the pad that is connected to the ground plane because that is connected to more copper and that will dissipate more heat so it will take longer to heat up if not it will create a bowl of solder on the component so let's go to some components with more pins here we have some sop packages we start with this driver which is an sop of 8 pins let me show you two methods for doing this the first method as before using the fine tip we hit one pin on the corner and add some solder then carefully align the component and heat pack the pad and then slide the component keep the pad heated till you're sure that the component is aligned with all the pads remove the soldering iron and let it cool now we go to the diagonal opposite pin on the other side press the pin against the pcb and heat it up together with the pad then we add some solder remove the soldering iron now we can add solder to the pins jumping 2x2 so the heat will spread evenly through the component and not damage it finally if needed you can add some flux and hit again the solder on the first pin clean everything with alcohol and also remove any filaments with a brush but you will see that with this method the amount of solder on the pins is not even i mean yes it's a good solder and we can still have the curve but is not ideal another solution is to use the flat tip in my case i have the 2c model first we add a tiny bit of solder to the flat tip then slide the tip over the first pin and by that we create a thin layer of solder now place the component and make sure that is aligned and hit that pin once again so the solder will stick to the pin now on the other side add some flux to all the pins we add a bit of solder to the tip once again and then we press it against each pin one by one this process will spread the solder evenly and thanks to the flux the pins won't get soldered together if you think this process is still a little bit too slow another solution is the next we add flux to all the pads as before also add some solder to the tip but now we slide the tip over all the pins at once and thanks to the flux the solder will only stick to the pads and the pins if needed we do the process once again if you think that you need more solder this time we can see that the solder pads are way better and the amount of solder is even between the pins so if you have multiple pins this method is way faster and better for example here we have an sop16 format so let's try this again add solder to the tip and then slide it on the first pad now we place the component and we press against the first pin on the opposite side add flux to all the pins once again we add a little bit of solder to the tip now slide the tip over all the pins and there you go now add some flux to the other side and do the same and now the component is soldered in place okay now let's see how to solder the tqfp package as this atmega328 microcontroller using the soldering iron now using the flat tip add some solder as before to the first pin take the component with the tweezers and find the perfect position hit again the first pin so the component will stick in place now add some flux to the opposite side as before then we slide the flat soldering tip over all the pins the process should be quite fast then we do the same for the rest of the pins if you have excess of solder we add some flux and with a clean tip pass it once again over the pins now clean it with alcohol and then with the brush and there you go it's not actually that hard but soldering a qfn package with the soldering iron is quite hard to do so we will see that later but using soldering paste now let's see how to solder some electrolytic capacitors this might look easy but it's not that easy and that's because the pins are below the component and would cover pretty much the entire pad so first we add some flux to both pads we add some flux to the component as well using the flat tip we add a very small amount of solar to one pad i say a very small amount so it won't leave the component then we place the capacitor on top now you can hit the pin and press with the tweezers the component against the pcb now hit and solder the pin on the other side the idea is that the flux will have the solder to get under the component evenly and we do the same exact process with smd inductors we add flux to both pads and the pins of the component then we fill one with a small amount of solder using a flat tip press the component flat on the pcb and hit the pad after that we hit the opposite pad and add solder the smaller the component gets you'll have to be more careful with the amount of solar and the heating time now a difficult smd component to solder is a deepak mosfet and that's because it has a big copper area below that will get hot very difficult first we add some flux to all the pads and also to the component then using the flat tip we add a very thin layer of solder to the big pad now heat the entire pad for a few seconds and place the component over while still hitting it we have to press against the component as well so the metal dissipator will get hot once the big pad is in place we add solder to the pins as well this is not the best solution but is the best that you could do with the soldering iron okay now let's make some tests with the soldering paste and the hot air gun i have mine inside the plastic syringe with a metal dispenser so it's easier to apply for example let's solder some resistors or capacitors carefully we add a little bit of solar paste to all the pads then using the tweezers we place each component over their pads now prepare the hot air gun we set it around 400 degrees also adjust the airflow so it won't be too strong and push the components away start hitting the components first from around 10 centimeters and also try pointing the air as vertical as possible also move the air around so the heat will spread evenly once everything is hot and about to melt get closer and keep moving the air the paste will melt and grip onto the components you will see the magic and how the components will slide into their place let's see some mistakes that you could make adding too much paste will result once again into a ball of solder you could put the airflow too strong and that will push the component away setting the temperature to low will never reach the melting temperature but it will evaporate all the liquid so the paste will turn hard but don't solder to the component pushing the air from the side will also move the component and won't spread the heat evenly on all the sides hitting the component for too long this for sure will damage the internal circuit using the iron we only hit the pins but in this case the entire component will heat up now let's see some more soldering using the paste for better distribution of the paste we use a so-called soldering stencil i've ordered this together with the pcbs from gncpcb.com for only seven dollars more this is a stainless steel cutout with a mask for all the smd pads what you have to do is to secure the pcb between some other pcbs then you have to find the correct position of the stencil if the pcb is big add some tape to keep the sheet in place when everything is aligned we add some solder paste over the metal sheet then using a metal or a plastic spatula we drag the paste so it will spread evenly on all the holes remove the metal stencil and you will see that now each pad has a small amount of solder just the right amount place the components over the pads and again heat the air gun at 400 degrees and slowly start hitting the pcb get closer and you will see the paste melting and the component aligned in place that's how we solder a microcontroller with solar paste and the same goes for the qfn package align the stencil add the solder paste and drag the spatula over so we fill all the holes now remove the stencil and place the qfn chip over start heating the paste with a hot air gun and you will see that magically the component will get soldered in place sometimes you need to retouch some paints so add some flux and using the sharpest tip go over each pin and make sure they won't touch each other now here i have a micro b usb connector using the stencil we apply the right amount of paste i place the connector over the paste and align it now heat the base with a hot air gun at around 400 degrees slowly get closer and finally the paste will melt and all the pins will get soldered in place you can do this process for any other component that you want and if you have a lot of components on the pcb you can use the stencil and fill all the pads with shoulder paste at once and then reflow them at the same time with the hot air gun so this will spare you a lot of time especially when you want to make multiple pcbs where the process is repeating so guys i hope you will now lose the fear of smd soldering it's not that difficult and with a little bit of practice you can get very good results it's very important though to use good quality tools especially for the solder the flux and the soldering station having multiple tip shapes is also a good thing if you want me to solder any other type of components comment below with the name and the package and maybe in a second part i will do that i hope that you like this video and that you have learned something new if so give it a like and if you consider supporting my work check my patreon page links are below so thanks again and see you later guys hey guys electrolubs here this video just ended i hope that you enjoyed it and that you have learned something new and thank you very much for subscribing and maybe leave a like to this video and also activate the notification bell and a huge thank you to our patrons because as you know i buy a lot of modules components for my project so with your help on patreon i'll be able to have more time and more money to invest into this kind of projects and keep these videos going and going so once again thank you very much to all my patrons if you want to support me as well you have the link below and if you can support me on patreon just subscribe to this channel maybe follow me on instagram on facebook and join the community on therefore.i o so thank you very much once again and keep up you guys

Channel: Electronoobs

Views: 375,410

Keywords: SMD, soldering, tutorial, stencil, solder paste, station, iron, tips, Tecniques, EEVblog, small, QFN, SOP, SOT23, 0402, surface, flux

Id: fYInlAmPnGo

Length: 22min 49sec (1369 seconds)

Published: Sun Nov 15 2020