This type of chips easy to solder with soldering iron, not hot air --use good gel type flux --do not apply solder on the pad before placing chip! --you can use big paper clip to hold chip on pcb So, apply gel flux to pads, place chip and touch legs on the corner using slightly "wet" tip

Adrian I think it's great to show something you're _not_ good at. Many things take practice and effort to get good at. I think it's important for us all to remember that. Kudos for the great video!

Homemade memory, that's pretty cool.

I like that you always show your learning process and mistakes - it's all too rare in the world of KZfaq. Great to see that it worked out in the end!

Adrian - great job! Your attitude of open mistakes is really awesome. Reminds me of Richard Feynman's discussions on how in science there is a bad habit of publishing only the working solution and not sharing all the dead-end learning - which he found incredibly valuable.

Adrian: THANK YOU for sharing the disappointments/mistakes as well as the successes. I've got 40 years of software expertise, but only recently started getting serious about electronics work, and it makes it much less discouraging on my old eyes to see others going through the same difficulties and sharing what they've learned in the process. Congrats on the working modules!

Its easy to get frustrated while learning, but remember, your attitude about it makes or breaks your confidence and patience. Give yourself some credit, and keep a positive attitude. Everyone had to start somewhere with something new

For solder paste, you're supposed to use a PCB stencil, which has cutouts for each pad. You line it up and then just smear it across the board. EEVBlog made a great video on it, it's episode 415

This is literally amazing. I've always wondered about homemade modules.

One of my favorite parts of your channel is that you don't edit out mistakes or the challenges you experience. I love that we get to experience that with you. I really enjoy watching you work through the problem and finding a solution. So many people could benefit from these skills!

I’m glad people are making kits like this. The Apples and PCs still can be useful. Just because they are old does not mean they should be put out to pasture.

Dont beat yourself up. Mistakes are great learning experiences. I love your channel and all the work you do. Keep it up! Thank you good sir!

Thanks Adrian, with all the hours seen Rossman soldering videos and now yours i´m much confident to try surface soldering. Greatings from Argentina!

0:15: "Ways ago, back in july." Haha, July? That's not that long a... wait!!! 😳

Apply the solder paste using a stencil. MUCH easier, and the stencils cost almost nothing from JLCPCB and the other Chinese suppliers. And also - the solder paste contains all the flux you need.

It's nice to see how much effort people put into keeping these old computers going (and I very much include you in that Adrian). I must admit I nearly skipped this video thinking from the first part of the intro this was going to be just a video of Adrian installing some RAM chips in Macs, which didn't sound very interesting. That will teach me because of course it was really about him making some SIMMs, which I did find really interesting (and glad to see they worked).

That was a truly use useful video. I actually have a ton of RAM myself, in fact I just got a tester which should arrive today, but you never can have too many 4mb 30 pin modules. Great tip!

Great video , I'm glad you showed the learning process even though it was frustrating. It was interesting to watch.

You do have to say, it is very satisfying to use DIY RAM that you hand-soldered. I love your moments of humility, they are hilarious... but don't be too hard on yourself =)

You are doing a great job! And it's fun to watch

Adrian I know why I like watching your videos, you’re just so normal like me trying to solder, not the best! You seem a like a great guy to know and keep up the great videos! I’m always learning something I either forgot or didn’t know. Also the Commodore book I did get on Kindle and it’s been fantastic. Boy the mistakes they made back in the day but a lot of fun to read how the Vic and 64 were developed was fun also the PetJet antics!

Hello Adrian's thanks for the great video and your soldering skills look like they are improving I have been working with electronics for 45 years . this ram will come in handy when finishing restoring my Mac Se/30 .

Soldering is an art. Takes practice, knowledge and control.

Great video, I never even thought of searching for a project like this. So my 386 and 486's will be very happy in a few weeks. I can't wait to see if my 386DX-40 can do 8x 4MB modules

Dude, I'm glad you shared the mistakes because we ALL make them, but wow bless you for never having watched a video on how solder paste works! That being said your brutal technique worked okay to be honest! Probably not on anything with a finer pitch or smaller components though! You mostly made it hard by adding flux. That made the paste slide around and stopped your components from "sticking:"" Alternatively, since you have a hot hair station use a clip to hold the chip down, apply gel flux and hot air and touch your solder to each pin, or just use an iron if your hands are stable enough, these chips aren't that tiny. Solder paste only realy works when you have a stencil. You don't need flux - the solder is kinda sticky to keep your parts sliding off once they're stuck into it. It's supposed to be a bit like a glue in a way. You had a lot of trouble because the flux made everything slide around.

Making memories with your viewers, such a wholesome channel.

Love your videos bud. Easily one of my favorite channels.

Awesome!! My very first computer, I wanted 8MB, so I ordered 2 4MB SIMMs. When I tried to boot, it didn't recognize them, so then I learned that my 386 required banks of 4 SIMMs... So bought 2 more rather expensive SIMMs... DOS had no use for 16MB, and I didn't yet have a hard drive, so I created a 12MB RAM disk which I unzipped a couple of floppies into on every boot. Fond memories indeed!!

Great video again, every day is a learning day and hopefully your video will help others learn. Solder paste is best left for when you have a stencil to restrict the amount of paste on the pad. Too much paste will cause solder balls to skate around on the board causing bridges some visible on the legs but others not so much behind them underneath the chips. If you have a stencil and some good quality paste designed for the job at hand then it can out perform soldering chips by soldering iron. The other thing to consider is the thermal shock to the chips, some are super sensitive to the temperature changes and others wont last if kept at too high for too long. If I had to fit these chips and didn't have a screen printer, pick n place machine, & reflow oven, then I'd use a nice pointy iron tip with some thin diameter tin lead solder. As others have said, apply some flux to the leads and pads. Apply some solder to one pad in one corner. Solder the chip in place on the one pad and check for squareness and positioning. Once happy, do the other corner and double check positioning - because its easier to fix it now than later. If all looks good, solder up the other legs. I was always told I used too much flux but my joints were virtually the same as what came out the reflow oven. You can use the same method to solder other smd components - solder one pad, position the part on the pads and heat up that one pad. Check position and solder up the other end. Flux is important and cleaning that off when finished is more so. Hot Air Guns are really only used when removing parts from a board. Tip: clean off the board with some IPA, use a cotton bud to help move the fluid about and remove stubborn deposits. Check the ideal operating temperatures of the paste / solder wire (too hot and you'll burn off the additives too soon).

Soldering paste is applied with a stencil in the desired thickness and a scraper, so you get the exact amount you need on each contact (only). That way you only apply soldering mask ones, then place everything, and run over it with the heat gun once. Just about every custom PCB supplier also offers to make stencils.

"J" lead style SMT chips can be tough to solder as the pins go under the package. Strip-soldering them might work if the PCB is pre-tinned with solder then cleaned back off, to get minimal solder on the pads as a wick. Use lots of flux on the PCB and then tack 2 pins of the IC with the iron, then strip-solder the rest. The hope is that the small amount of solder left on the pad is enough to wick (pull more) new solder in and not having a lot on the pads should stop pad-to-pad shorting from solder "squishing out" from the J-lead & package being pressed to the PCB pads. For hot air, I think your only good choice would be to try and get a stencil for the (JEDEC I believe) J-lead package style. A toaster oven converted to a reflow oven would be the better way to solder in this way, but you could get away with the hand tool and a hot plate. Using a DIP style hot air head would help to get both sides heated up at the same time and prevent over heating the IC and PCB. I agree 63/37 solder is the best way to go. Using lead-free would be a nightmare. Looks like an interesting project :D Cheers,

Making your own RAM is pretty darn cool. That's a very useful project for restoring old computers!

Cool stuff, I'm glad to see someone has figured this out.

You're so hard on yourself! Surface-mount stuff is REALLY difficult, so I give you tons of credit for even trying!

Well done an amazing video and great work on your part

Nice that you found out this oldschool technique. In the late '90 I worked for a wholesale computer parts supplier and to make more profit and sell for lower prices than the competition we bought separate chips and empty ram boards from China and just make 30-pin simm memory modules ourself. We also had a dedicated simm memory tester for quality control.

hey ! i'm sure you're now ready to solder smd components with solder paste ! i'ts nice to see that some of us are working fine to keep going with older macs

Adrian, as usual it was a nice video! Keep it going man! As for the soldering, you could try this technique: First, apply some solder paste. Not much, and use an old credit card to help spreading it evenly. Then, you use the heat air to make the solder stick to the pads (here you will see how nice it magically goes to the right place). And finally you place the chip as you did on the first ones, holding with the tweezers, but not pressing too much against the chip. Hope that it works better for you! Much love from Brazil!

Don't worry about refrigeration of the solder paste. It's fine because you hadn't opened it yet. Once you have, you only need to keep it cool for long term storage. I've also had bad luck trying to hot air solder SMT using solder paste applied with a squeeze tube. I've had somewhat better luck using a stencil to apply the paste, at least for .85 mm spaced parts, not so much with 0.5mm spaced ones. Setting the chip down correctly, and removing solder bridges has been the major problem. I've actually done better with a VERY fine tipped soldering iron and VERY thin flux cored solder wire. QFTP and SOIC chips are easier than QFN! I have a binocular microscope to inspect my work. I think it's a 20x power (eyepieces are marked 10x, objective is marked 2x). It was a lucky find in the dumpster where I worked. Just had to make a home brew stand for it.

I'm pretty competent at through-hole, but surface mount soldering is pretty new to me too. You're in good company.

I do this kind of work professionally and there are two ways in soldering J-Style SMD-Chips to P.C.B. that I prefer. The first is to use a tiny amount of Epoxyglue to fix the Chips in position on the clean (No flux etc.) Board and solder them with special SMD-solderingwire (0,3 mm Diameter) using a microscope. The second way is to plot a solderingmask and use it to portion the solderingpaste on the pads. After removing the mask I fix the Parts with ceramicglue (extremly fast) and use hot Air with 320 Degree Celsius. What you do is great, cause I had to search a long time to get hand on such SIMs . Good work, and greetings from germany!

Yes you are correct video mem was shared. The LC III I used back in the 90’s was a pig in mud until I threw more rake at it. Good job

Nice interesting video. I like it that you don't stop the camera on the learning curve with smd. I only use dip components because i'm also afraid to mess up starting up smd soldering. After seeing this maybe i'll start with it

That is a nice upgrade for the Classic II! And I truly feel your pain with SMT. I have a half-finished EasyFlash 3 cartridge downstairs waiting for the inspiration to continue soldering the SMT resistors and caps that I can barely see.

When I first started with surface mount soldering, I used solder paste in similar applications to this. it helped me get a lot better at hand rework. Keep it up and you might be doing rework at a professional level in a short time. That said, I definitely agree with the other people saying to use an iron for this application. The solder wicks around the legs really easily using an iron and a bit of flux, and doesn't warp the small/thin PCB.

I knew as soon as you said solder paste and months ago, I said right out loud, "Not refrigerated, this is not gonna work..." the super tiny soldering tip is a must! You should also purchase the needle VOM meter leads too... they are a must as well...

Very cool! When I first started doing smt work I actually made full stencils for the pcb’s I was using from overhead projector acetate and a cnc hobby cutting machine to make the holes and then applying the thin layer of paste using a plastic card to spread it over the stencil. It works pretty well, but I found you need pretty good accuracy and steady hands to place the chips. I don’t have steady hands. 😆 With all smt work these days, as it’s just prototype stuff, I always go the ‘lots of tacky flux and flood solder’ route. I’ve not tried j-lead or qfn, but you should be able to do it ok with flooding I think, but probably more awkward than soic or qfp. I usually put some tacky flux down on the pads, place the chip, then just flood with solder and tidy up with wick where needed. So much is just practice, and learning to keep your cool. 😆 Even under good conditions it’s a frustrating thing to do, but compound it with essential tremor and the patience of a saint can be required at times. I mostly use hot air just for removal these days, but everyone has their preferences and abilities. Great videos, keep on doing what you do. 😄

Great way to get ram into the classics if you can't find any. For soldering the ic's, there is no sarcasm behind this, there are some really good videos, PACE is one of them and remember flux* is your friend (the no clean one). Great video.

Video: is almost 24 mins long. Adrian: NIBBLE SIZED

DUDE! thats F'n awesome you made your own RAM!

Some tips from my own experience that I haven't seen mentioned: -If your solder paste is dried out (it does contain flux by the way, that's what the solder balls are suspended in to make the "paste"), simply squirt some of it into a small disposable container (like a plastic shot glass, bottle lid or similar small well) and then add in a bit of paste flux and stir. This will thin the paste back out and make it apply much more evenly. When doing small hand work like this without a stencil (using a stencil is much easier, so get one if you have the chance when ordering a design yourself) I will often use a small slotted jeweler's screwdriver to transfer my "renewed" paste to the pads. You don't need to be perfect, it's more important to just have the paste in the right ballpark and to not have too much on the board. As you found, the hot air will "magically" wick the solder where it needs to go if everything works right -You want to get away with the lowest hot air temperature that still melts the solder in a reasonable timeframe (5-30 seconds, not minutes). This will minimize the chance that you damage the chips or board with excessive heat, like the warping you got. What I find really helps is pre-heating the board part of the way so that the hot air doesn't need to be cranked up as much to get the solder to melt. There's proper heating plates for this, but you'll get a lot of benefit by using cheap alternatives you might already have. Some suggestions are a thrift store cooking skillet/hotplate turned as low as it will go (don't use it for food afterward!), a 3D printer heated bed (this is what I use), or one of those heated silicone mats off amazon for opening up phones/tablets. Basically, anything flat that can get the board to a controlled 100c-150c will make a big difference and won't harm the board or components, making the hot air step much quicker and less likely to cause damage -Solder paste comes in three typical "Types" usually labeled T3, T4 or T5. This refers to the size of the tiny solder balls in the paste, with the higher numbers using finer balls. Since the smaller balls have more surface area and flow better, they're just straight-up easier to work with for hobbyists and the price difference is negligible at this scale. The MG Chemicals stuff you have looks like T3 (the largest and hardest to work with), so if you do end up ordering another syringe of paste at some point, make sure to get the T5 stuff. Sometimes it's not a major difference depending on the kind of work, but I'll take every advantage I can get when doing this kind of tricky hand rework! Other than the above tips, it's mostly about practice and technique. The exact airflow, temperature, and hot air positioning and angle all influence how the paste and chips will behave, so experiment to find a method that works for you. In general notes, I usually do wide circles a few inches above the PCB/chips to get the board "close" to melting temperature, then bring the tip in really close to quickly melt the solder and ensure the chips and board stay in the "danger zone" temperatures for as little time as possible. Thanks for all the great content you make, and especially thanks for going deep into the details of your full process and troubleshooting, including the failures and challenges! It's very helpful to others, especially those starting out in electronics, to see that the path is often far more convoluted and challenging than some perfectly produced guides might indicate! Always keep pushing and learning new skills, it will always pay dividends down the road.

9:45 "The paste doesn't have any flux" ... huh solder paste is literally tiny solder balls in suspension in a gel flux.

great vid adrian. i was nervous when i first started smd soldering. but over the last year i can handle 144 pin fpga’s easily now. i dread any through hole soldering now.

Best way is with a small amount of solder paste on the pads only and then gently put the SIMMs on a flat electric frypan / skillet. I've done a ton of SOJ+SIMMs this way!

really loving this video! its exactly the motivation and knowledge i need to try a heat station and smd myself; I think you could do a perfect job with the paste; trying to remove them without a ton of flux will let it get overheated more often

Adrian, everyone has to start somewhere with new techniques. You can make the paste more liquid by warning it. I would do the bypass caps first too. A vacuum pickup can also help. You can get a really cheap air bulb one for about $1-2 so worth trying. Practice with the bent one a few times or practice with an old PC board. Good luck. Personally, even though I have experience doing SMD rework I would probably have slip soldered the legs with a soldering iron as they are visible along each side. get a large rounded chisel tip with a dip in the flat face which holds a bubble of solder. Good luck, I really enjoy your channel.

Okay, this is fucking sick. Imagine soldering something together yourself and putting it into a motherboard and having it work!

I always appreciate these videos. You are always so positive and it's a welcome break from doomscrolling. You're doing great! Surface mount is a very different kind of skill. Once the pandemic is over I can highly recommend Jessa at iPad Rehab for microsoldering training. They have a one-week course that was incredibly instructive for me. It's centered around phone repair but if you can do microsoldering on phones the type of work you're doing here will be child's play.

To help with the warping, you might spend a little time blowing hot air over the whole PCB to warm it through before going in hard to solder. Also, solder stencils all the way, will really help to ensure just the right amount of solder is applied. 🙂

Oh my, one can sense the frustration! These chips are massive, they should be very easy to solder by hand. Just use thinner solder (0.5mm), tack solder one pin, then the opposite one, then put some flux and solder the rest. Great to see that the modules worked.

I learned SMD soldering via a similar method to yours! First try was a disaster, I discovered that with solder paste, a little goes a long way! I used a toothpick to smear a film of solder paste on to a flux treated PCB I used two techniques, for some things like ICs I would heat up the solder first until it was evenly distributed over the pads, then I used tweezers to place the IC onto the tinned pads and used a little more flux carefully heated the IC until, like you discovered, the chip dragged itself into place. Other times I would skip meting the solder paste and applied the component direct to the pasted pads fluxing before hand. Experimenting with the airflow can help, using a lower speed can help you get the nozzle a bit closer without knocking the component off line and prevents random pieces of solder getting splattered around the PCB. I think it's just a case of feeling out what works and from then on just refining your technique. Now I find SMD soldering so easy I wonder why I didn't learn sooner!

This was awesome! Don't be so hard on yourself, how else are you gonna learn without screwing up lol. I do, we all do. In many, many ways haha

Louis Rossman will be screaming at the screen. "Heat the board" Fair play at having a go, many of us would be like erm nope.

Ive been watching to many of these videos.. When I heard you were wanting 10mb of ram I instantly thought what on earth could you even do with so much memory?!

Soldering like these always amaze me when the solder just jumps into position. I tried my hands in SMD soldering a couple of days ago, I bought little PCB christmas trees and I have to assemble them by hand, 3x4 SMD LEDs, 4 SMD resistors and a triode. These components are so tiny, I had a hard time with it and I tried regular soldering iron. The good part was that the pads were already tinned but I had hard luck assembling my first attempt (bought 6 of them). I should try the heat gun for my next attempt.

Nice work, it always amazes me how members of the retro community figure out how to get round shortages of items. I suspect at some time in the future someone will come up with a replacement for the classic mac screens using a TFT screen as a replacement so that we can get round the shortage and failing nature of old CRT tubes, also means we can get rid of the dangerous voltages as well.

Now you have memories from 2020 :) Soldering tip: place the chip w/o soldered pins, then solder one pin by hand. It's fixed now and the remaining pins can be soldered smoothly.

Some tips for the road: - Use a thin film of solder paste next time, spread it with a silicone pick or an old credit card across the leg pads. It doesn't have to cover the entire strip of each pad, just be on it. The heat will help it flow into place. - You don't need a stencil, but it does help. In a pinch, you can use something like a Cricut to cut some card for a one-time-use stencil. - When using hot air, it's helpful to heat your boards from underneath. This prevents the bowing of the boards from thermal expansion. There are professional solutions for this, but you can also get away with hot plates set on their lowest setting to help lower the amount of time you have to focus on a chip. If you can reliably have your hot plate sit at around 400F/200C, it can flow the entire board for you. If your hot plate has hot/cold zones pretty bad, a thin layer of sand at the bottom will even that out to a gentle, consistent heat. - When going at a chip, try to use a more broad tip for your hot air gun. Paste works best when the entire footprint of the package flows at the same time. That way, it can destress and flow easier and build more consistent tensions around the legs. This is something I had to get wrong a few times before I got the hang of.

When something like that says to keep refrigerated, that usually means after opening and breaking the seal.

When you order your PCBs you can order an SMT stencil that helps to get the paste only on the pads.

Not bad for a first try soldering SMD. Those SOJ chips are a little tricky if you've never done it before, but it looks like you're picking it up pretty quickly. And you've got plenty more to practice on! 😁 Hopefully you've got enough there to upgrade a few machines. But if not, the gerbers are available so you can always order more!

If you want to see an expert at SMD soldering, I recommend tronix fix. That guy is amazing! He doesn't reball APUs, but other than that he fixes modern gaming consoles. Another good one is HDD Recovery Services. He recovers dead hard drives (which sometimes requires chip swaps) as well as USB drives, SD cards, etc... He uses thermal paste all the time. HDD services always pokes the chip to verify that it will slide back into place to know it's correct. Oh and paste is not required. I see them take a big solder blob and just drag it down the line to pre-tin the contacts. Once you put the component on you can drag the soldering iron across the pins. It doesn't take much solder. Oh and both channels use a microscope.

Does it feel slightly faster to you because the upgrade uses lower latency chips than those soldered on the mobo ? I believe they came in 50, 60, 70, and 80ns varieties; with 60 and 70 being the most common ? Would using some 50ns possibly squeak out a little more responsiveness ? Would also replacing the mobo chips with 50ns instead also affect it a touch ? Do you feel the need to have the fastest Classic Mac on the block ?

at 1:20 , am I the only one that saw something fly from Adrian's hand? Hahaha. Nice video man !!!

i did some smd soldering a couple weeks ago, and since i don’t have a hot air station, i used the soldering iron to heat the paste and it actually worked really well. i can’t check until tomorrow but i think the soldering paste i got has flux, so that might have a little to do with it, but after the first few like that it was super quick, unlike the one i tried to do with regular (not thin) solder wire which took ages.

I recently bought a hot-air station. Like you said, it takes time and practice to get good at surface-mount soldering. To get some practice, I decided to remove and re-attach every component on a cheap DDR2 memory stick that I don't really need :) Also bent boards can be straightened if they are bent to their original state, fixed somehow in this state and heated up to less-then-solder-melting temperature for some time. Some folks even do this to fix bent PC motherboards.

And before I knew just what the video was going to be about, when you were talking about the rare high-capacity 30-pin memory, my immediate thought was "gee, sounds like some project some hobbyist group could come up with; some way of making substitute memory". And so what was the video about? Exactly that. But as you were soldering, I could just hear a Louis Rossmann commentary about how to solder going on in the back of my mind.

Very experienced soldering iron/hot air wielder here: If you don't have a stencil like in your case, tin the pins with your iron so they each have a tiny mound of solder on them. This is enough solder. Then just cover the IC legs in flux (your flux pen is fine) and add plenty of flux to the board and it'll work. You're 95% of the way there. More flux and pre-tin the pads and you'll get it next time you try! This saves you having to worry about having too much solder.

I mostly do this stuff with a soldering iron with a fine tip. I had to learn this too, screwed up a lot of PCB’s teaching myself how to solder SMD stuff.

I do the odd bit of SMT soldering, most of the time its mounting though hole parts where SMT is supose to go. It is a little tricky & fiddely, but you do get the hang of it.

I must say well done Adrian!!!! I too do not go near SMD soldering for the same reason as you. It requires a certain skill to pull it off. Well done, great job!!!

Way back in the day a Friend of my Mother's worked for a PC Repair shop. The Repair shop's owner cleaned out the back room and since I worked on Computers the guy gave me 6 boxes loaded with old parts. In one of the boxes there was a odd looking RAM board. It had two 30pin edge connectors with short ribbon cables around 5 inches going to a bigger board that was populated with a 72pin simm socket. The board had a couple of jumpers and misc logic on it. I never got a chance to try it but it looked like it made a 30pin simm based system use 72pin and used two 30pin sim slots. I have no idea what company produced, looked kinda home made since I remember seeing a bunch of flux residue on it.

With solder paste it needs two stages of heat. one is just below the melting point to get the flux flowing and then increase to reflow the solder. Solder paste will have a reflow pattern data sheet to show the temps and time needed. When I do this with hot air I have a nice thick stone tile with a polished top so I don't damage my desk or silicone matt. I also never liked the paste from a syringe and had the same issues you did and would use something else to apply the paste. A stencil is so much quicker and saves a lot of mess, but for the number you have it's expensive. Soldering with the iron and plenty of good amtec bga flux is a lot easier for a small number of chips like this.

Seeing that you struggle with certain soldering jobs does give me hope.

Use a fine tip soldering iron, 1: place a blob of solder on one pin. 2: place component on pads and aline it with pads, 3: solder first pin, 4: solder a pin on the other side of component, 5: solder the rest one at a time, clean. Job done. Also get yourself an ESD mat and strap to give the chips a chance.

Finally! I have found another Mac Classic II owner!

I know you are getting a lot of helpful comments (some mean) but I just want to say that your absolute first time using hot air and solder paste was honestly not all that bad. I've seen far, far worse. It was absolutely not a "Horrible job, as usual." as you said. The whole point of soldering is to make electrical connection. That's it. Everything else that anyone says is just help to try and get the most consistent soldering results. Notice I did not say "the best" just consistent. And the only way to get there is to just practice over and over again. That is all. You did MUCH BETTER than the average first-user-starting-out-with-fine-pitch-soldering. I used to run a little side business where people would send me soldering jobs they tried to do on their own, and failed. And boy let me tell you some of them were downright awful. Yours would have been a rare treat to try and 'fix'. But honestly that PCB absolutely does not need to be soldered with paste. You could do that entire board in a couple of minutes with just your TS100 (Mine is finally dying after years of steady use! I wish I had a TS80 to replace it with) because of how the solder flows. You just tap the iron tip to the leg and it wicks right in. I've done literally hundreds of them that way. Yes. That means there is no flux in the solder on the iron. We have plenty on the board gel or otherwise.

A dedicated toaster oven can be used for surface mount. Instead of having a temperature controlled PID, I use a simple trick: I place a small length of fine solder wire on one of the PCBs. When it melts you wait a few seconds and it's done.

I soldered SMD with hot air only once in a small workshop. If I remember correctly you place a chip on the PCB then put some paste at the pads/pins (e.g. in a small line). If you heat this up the flux in the paste should pull the chip and the solder to the pads automatically. If it doesn't work add more flux and reheat. In hard cases you can also use a hot soldering iron and draw it along the pins.

Ordering and using a stencil for applying the solderpaste makes the job much easier. ;) but a nice idea and solution. Nice channel ... Go on.

I would recommend taping over the edge connector pins to eliminate the risk of getting any stray solder on them.

Every time you get ready to power something up and say, "Ok, here we go." I add my own sound effects and say, "BOOOOOOOOM!!!!!!!!!" 😆 Does anyone else watching these videos do that, or is it just me? 🤔

Coolest channel video intro on KZfaq.

Adrian, I would suggest watching some of Louis Rossmann's MacBook repair videos for tips on SMT soldering with hot air - it's amazing to see how 'sloppy' you can be when applying the solder and how well it comes out. You will notice he uses a lot of flux (available from his store) to heat up the whole component, not just one side. I think you will learn a lot from his videos - I know I did, even after 40 years as an EE.

Hey nothing wrong with learning a new skill! Personally for "larger" low-volume SMD stuff like this I don't bother with hot air. I start with clean fluxed pads, tack in the chip on opposite corners, and solder each pin one by one with a fine tip and a roll of fine solder. Slow but I find it much more forgiving. Cheers!

I’m a total noob as well and had always been scared of smd. Finally got brave and bought a hot air station. Now I actually prefer smd instead of through hole. I’m 50, with bad eyes, and shaky hands, if I can do it, I know you can. I have never used a stencil, and it would probably make the job easier, but I am living proof you don’t need them. The trick is getting the right amount of paste. It’s ok to smear the paste on if you use a consistent amount across al the pads. Be a little conservative with the amount you use, and you don’t need to pre-flux, there is already flux in the paste. Get the chip close to aligned but it does not have to be perfect, surface tension of the solder will pull the chip into place. If you do get bridges, take your soldering iron with the tip cleaned of solder and just touch the pins, the excess solder should flow onto the tip. If you have a stubborn bridge, hit it with the solder wick. One last thing, be mindful of how much air you are using, the air can blow small parts out of place. Thanks for another great video Adrian.

I would only use solder paste if I had a silk screen and was just using hot air to solder it. You're better off tacking the chip in place at either corner, apply flux and then tin your iron, touch each pad and the solder will travel off the tip onto the pins. Keep doing that until there's enough solder on the pins. Rework with heat if you want it to look nice and even. I've done chips smaller than my fingernail of my little finger that way with no problems.

Hey, they worked though, can't argue with results, hehe. I'm impressed by anyone who can solder intricate little components like that, I don't have a steady enough hand for it.

That brings back memories.... back in the times when you paid 100 bucks per megabyte I made PCBs and soldered ram chips into them to get 4 additional 1MB modules for my 386... and then I had to replace one ceramic cap with a SMD version on every board because it collided with the simm socket....

I think the technique you used was out of order. You should have 1) Apply flux to the pad 2) Place the Chip 3) use a small bead of Solder paste on the outside between the legs of the chip and the PCB 4) apply hot air then use a solder wick with flux to remove any soldering bridges. It would have been easier for you if you has a stencil as mentioned before in the comments.