MacroFab Engineering Podcast #303
Tip Resurrection Cream
How is it possible that Stephen and Parker can talk about solder and soldering supplies for over one hour. Listen to this weeks episode to find out!
MacroFab Engineering Podcast #303
How is it possible that Stephen and Parker can talk about solder and soldering supplies for over one hour. Listen to this weeks episode to find out!
Ever have PCBs that solder just will not wet and solder to? You probably thought it was improper soldering technique but that was probably not it!
This week Stephen and Parker were supposed to discuss bench equipment for development and testing but got distracted by talking about home-brewing beer.
What kind of soldering equipment should an engineer look at getting for their bench? Parker and Stephen start discussing equipment and supplies!
Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Stephen Kraig began his electronics career by building musical oriented circuits in 2003. Stephen is an avid guitar player and, in his down time, manufactures audio electronics including guitar amplifiers, pedals, and pro audio gear. Stephen graduated with a BS in Electrical Engineering from Texas A&M University.
Special thanks to whixr over at Tymkrs for the intro and outro!
Welcome to the Mac fab engineering podcast. We're your hosts
Parker, Dolman and Steven Gregg.
This is episode 303. So last week, we were talking about solder equipments. Like the Yeah, soldering equipment, right?
Yeah, like irons and things like that and hot air guns.
Yeah. So I think this week we're gonna talk about soldering supplies and consumables, which is a, this is stuff that you like continually use up. I guess we last we talked about soldering tips, which, um, because we can throw into consumables as well, again, we can talk about that topic because we only lightly touched on it last week.
You know, I don't know if I would put a tip in a consumable even though it does wear out and you replace it. I would still consider a tip like a tool because I choose them based off of what I'm doing. And the frequency at which I have to replace them is so low. I don't know if I would consider it a consumable.
Yeah. Okay. Go refer to last week's podcast and because I think we did talk about like, chisel sniper tips, conical tips, that kind of stuff. Never temperatures, stuff like that. So let's start with solder. The fudge is such a weird word, looking at that word, pronouncing it solder.
I mean, pretty much everyone pronounce it incorrectly. The first time they see it, right. Yeah. Just like chassis. Chassis Cesis.
I guess I've never I don't remember that. You never did that. I
had to be corrected. I remember the first time I said that and said, Well, I probably
said that for that right, dude. It's probably the first time I said that was like 25 years ago, though, at this point. So who knows?
Right, right, right. So solder comes in a bunch of different flavors, right? Yeah. Cool. Ranch. Nacho cheese
cheese.
Yeah. Screaming jalapeno.
Those that's the best flavor. So yeah, that comes there's different kinds of solder out there. So I guess we can talk about different kind of like alloys because they're alloys. Well, I guess technically. Es. blends. Yeah. Is other alloys. But there is one that's not an alloy. That's 100% tin.
Oh, that's true. Yeah. Yeah. What is? What is the naming for that? Like K 100 or whatever?
What do they call 100? Caster? Right. Right. Right. SN 100 sn get done. That's in essence 10 On which is kind of weird. Why is it SN on the periodic table?
Wasn't there some like ancient name for tin? That was
SN? That's probably it's probably Latin for tin. Yeah,
yeah. Yeah. Let me look. Now you got man, this is gonna be a fun. Oh, I typed in SN I'm sorry. I get social security number. And I'm trying to look for tin. Yes, Stan, sta and u m, is the Latin word for it.
Totally makes sense. Why it's why it's so. Yeah. Okay.
I'm just like peanut butter for lead.
Yeah, PV. So, I guess we can separate this out into lead and unleaded.
Okay. Okay. You mean so mean? Good and bad. Right.
Good. Well, good.
You lead is not inherently good.
Yes. So think about lead lead solder is. That's what old electronics used to be made with. Used to be pretty much what all hobbyists used. I know there's a big movement for hobbyists to go to lead free, especially since now like decent soldering irons are, like affordable. So it used to be like if you had a RadioShack arm, there's no way you're gonna do lead free solder.
Right right. And lead solder is also easy mode. So it like it made sense for hobbyist level because the total amount that a hobbyist would use is peanuts, right? Yeah,
yeah, it not a lot. But ever since 2005, slash six in production and basically anyone that sells electronics you pretty much have to go lead free. So for leaded because I have roles or both. And what you need to make sure is if you're going to have both processes on your bench, you need to have different tips for your, for your and different actually pretty much separate equipment for each one, you got the same handle, that's fine, but you'd need different. Like if you have tip cleaners and that kind of stuff you need separate out PB verse, lead free because the moment lead gets into the lead free section, it will never leave. It's always going to be contaminated.
So the general rule of thumb is don't use lead, like you use lead if you lead is the is the harder one to use. I mean, I apologize. Lead is easier to use, but it's harder to deal with. So it's one of those situations is if you know you need lead, then you can ever set up for that but in general just don't.
Yeah. Now I home I do pretty much 90% lead ID and then 10% lead free is basically what I do here. Now I've Acrab it is 100% lead free. Like we don't have a lead ID line at all right? So for solder for leaded, if you're going to go lead, I would say most pretty much all hobbyist probably have a lead set up. Probably they probably don't even think about having separate though, like a separate tip for leaded verse unleaded. But it used to be you can get was 3763, which is the ratio between lead and tin in your solder. And that was like the golden number ratio. And there's like some chart on like, like temperature and pressure and like the alloy and like, like, like the different mixtures and like there was like a sweet zone at 6337, which was like, like it had like the magical properties of bled. Now it's the Mork worlds. Yeah, actually, basically, yeah. Now, so that's easy to find is 6040 6040 is a lot more common, and a lot cheaper. I don't know why it's cheaper. Maybe it's just slacker process controls. So it's easier to make or something like
that. It's easier to calculate 6040.
Could be Yeah, you can still get 63 No,
6763 37.
Yes, yes. That I said the first the first time. Yeah, you did. Yeah. I think I have, like a couple feet left of like RadioShack. Leaded, and, but so I mainly use 6040 If I'm using leaded now. So what about you on leaded solder
6040 is what I use for leaded stuff. Let it stuff is so easy in general to use that. I haven't noticed a significant difference between those two alloys. And 6040 is readily available. So I go for that. Really, honestly, when I'm buying leaded stuff, it's just if I want the flux type, you know, whichever one no clean or if it's clean Nessus. Yeah,
yeah. So I was gonna get into that mostly with. Well, I have a whole section on flux. But yeah, so what you want to do is you want when you're buying solder, you want to get what's called Flux cord. So the flux is solder is actually hollow, and it has a flux core inside of it. Now, you're going to usually add more flux to your solder joints. But this aids the flow of the solder itself, as it's like hitting the soldering tip and the joint itself. So you want to you definitely want flux core.
If you don't have flux core, you have to add your own flux 100% And nothing will actually stick
and nothing will stick at all. So yeah, 6040 leaded is usually you know, you don't have to go out of your way to get the other blood. Now on the lead free side, I use two different types. I use sn 100, which is 100%. Tin. And then also we use what's called sack 305, which is a blend of tin, silver, copper and something else in there. And in 305, like describes the ratio. Oh, there's Oh, that's right. There's another flavor of lead ID which is 6236 Two, which has silver silver in it to silver silver leaded solder, which is really good too. That's like, that's, that's pretty high dollar stuff.
Yeah, you spend more for it. I've certainly bought reels of it. And it's nice. I don't know if it's I'm sure it has applications. And however most of the applications I've ever seen have just been like, it's good because it has silver in it. And
that's exactly why I see. Yeah. joints that you make with it are definitely really shiny.
Yes. So So if if I guess if appearance is, is nice and you want something that's easy to work with six to 36 two does work pretty well. But it's just you'll you will pay a lot extra for it. Yeah,
any silver is expensive and because that's actually what's interesting with like all the lead free stuff, there's also silver lead free solder, which does the same thing. The silver, at least from my experience just makes it look pretty. Because like pure tin does not look pretty. It is dull. Same thing was that sack 305 is got a little more sheen to it looks a little shiny, but it's still not a like, you put a little bit you put 2% silver in there, man, it makes that solder joint look look amazing.
It's mirror finish kind of thing. I think I think that's that might be one of the like, I don't know the exact details about what would make silver solder better. However, just the visibility of the joints, I think makes people say like, that's better. That's arguably better because just look at it. Yeah, maybe actually, maybe because of the silver. I'm just shooting from the hip here. But maybe the visibility of the solder allows you to see imperfections better, or
that's what it is to.
Yeah. Yeah. cracks and cold solder joints and stuff.
Yeah. So at macro fab, we use all lead free. So we use sack 305 for all surface mounts. And then for through hole we use sn 100 basically 100% 10 So we have rolls that both two because our selective solder is 100%. Tin. I think yours is sac 305. And the pot though.
sec 305. Across the board is what we use.
Yeah. I honestly there's not a lot of big differences. It's just just different ways standardizing 10 bases like 100% 10 is a lot cheaper than sack there were five and use a lot of solder when doing through hole comparatively. But sock through five is amazing to reflow. So
pretty much well in terms of in terms of the non leaded world.
Yeah, and the non leaded world, Secretary five is amazing for for reflow. And the basically the attitude, the extra elements in there, and the alloy help it not What does what's called Tin whiskering. So, if you you can use 100% tin on surface mount, but you want to get tin whiskers and debugging tin whiskers is never fun. So now, whereas with through hold, you can get away with humps of 10 because your component leads are so far apart. A tin whisker, I won't say will never form that far away, but they typically won't.
Well, and there's a lot of things that go into whisker growth. And so yeah, so voltage being one of them. So so, you know, unless you're dealing with high voltage stuff, you're not going to grow whiskers, typically long enough to span the distance between through whole pads.
Yeah. And that was that the whole like PowerPoint presentation for NASA about tin whiskers. So NASA uses things like one or 2% lead, they have some special alloy space alloy for their for their stuff based on loi, space alloy, and it's got like 2% lead in it. Aviation is allowed to use some lead to sell their products because of basically any, it's like any percentage of lead kills tin whiskers, like it just won't, they won't grow.
So up to 2015 I believe it was devices that were used specifically in safety environments did not have the requirement of being led free. And effectively no Rojas but but I think in 2015 is when they had to switch over. So at my first job 100% of our stuff was was led just because it was super reliable.
Now, the problem with is this is why I would say start transitioning over to lead for especially for hobbyists to is there is zero safe lead that can be in your body.
Oh yeah.
Yeah, like the like I think there's like an OSHA cut off but it's like, we're finding that like any heavy metals and your body is like that's awful for your body.
I think metal poisoning is brutal. Also, Parker and I I we, there was someone when I was working at Mac, Feb there was someone that we knew who got it and not at macro fab. No, no, I apologize. Yeah. Not at macro February, separately, and we heard the symptoms and it was just like, oh my gosh, at that, you know, it was symptom management for this person, for sure. Yeah. They weren't able to really like flush the heavy metals out.
Yep. Um, so yeah, it's it's, so if you use leaded don't eat a sandwich while you're soldering. And I would say just follow some OSHA guidelines on how much you have to like scrub your hands and stuff. Do that. Don't rub your eyeballs that kind of stuff.
You know, a good point with that is when solder is rolled up on a reel and you you take a piece and then you stretch it between your fingers to make it straight. You're actually going to get a bit of dust on your on your finger. Oh, yeah,
yeah, you're robbing the lead right off onto your fingers. Right
right. So like there's a lot of actions you do that you don't think about that that happens and also, you know for us and let it don't put it in your mouth to hold on to solder or anything like that. Yeah,
don't do that either. Now, so yeah, I think there's some OSHA guidelines on scrubbing and that kind of stuff wear gloves if that's what you want to do. Yeah, there's no safe levels of lead that can be in your body or any kind of heavy metals either. So I mean,
I think that's a little bit extreme but like I I've pretty sure everyone gets what we mean. Yeah, no amount. Yeah, like don't even play that game. Yeah.
So again, soldering lead is fine just take the precaution proper precautions. And the thing about this I don't You don't have to worry about the fumes though. I mean, obviously you don't have the fumes but it's not like you're vaporizing lead when you're soldering.
So oh, just all the all the other tasty flux elements,
just the flux elements that that 60 year old rosin melting out of it.
Oh, gosh, it's like gross earwax.
Okay, so what brands of solder do you typically buy use whatever. Oh, well,
we use AIM aim at at work and then I think I still have some of Parker's old caster that I use for hobby stuff at home.
Yeah, I think we use I think we're a full customer. I think we have some aim. But Kesar aim buy from a reputable brand that has a datasheet basically for the solder so you know what blend it is you know what flux it is? What diameter
diameter diameter is is really big because the when it comes to hobbyists, I always I see a lots of problems with it, where they just buy ginormous thick solder. And in general, my mic advice is by smaller than you think you need, because you can always feed more into what you're doing. And you have much less chance of overfeeding if you if you have to feed a lot of thin stuff. In fact, I typically buy as almost as small as I can. What is it Oh 30. Or, I don't remember what what size it is, but but I typically buy as small as I can. And that allows me to solder the big stuff by feeding more in but it also allows me if I need to go down and put a small bit onto like an OH 402 pad or something like that. It's really easy to just snipe a small amount on there. Whereas if you have the big chunky stuff you buy at Home Depot or something like that, like good luck trying to solder and Oh 402 with that. Yeah,
the I think I just looked at the reel on my desk. It's Oh 31 Yeah. Oh, 30. That's probably a good starting point
for people that's really thin. But it is really nice, especially if you if you have a magnifying glass to solder with. You can really put just the right amount of solder and not overdo it easily.
Yeah, this is my last bit of 6337 Actually, no, I think that I bought this from EPO here in Houston. Oh, nice. Because I remember because energy chemicals and that's the brand name they carried. I think they still carry this too. This is Oh 25 which I think is a little bit too thin. I like Oh 31 the best. I do have a big, big old spool of I don't know how thick that is. I mean, look at that stuff.
Oh, wow. Yeah, that's like braising solder.
I mean, the acid is leaching out of it. So yeah.
Well, that's a good point. If you're working on electronics don't buy acid core.
Yeah, that's the next thing is is flux. What kind of flux should You be looking at using for hobbyist. Alright, flux 100%
You'll get you'll get the best results with the least amount of skill.
Yes, RF like that's what I use here. In my home shop, I use ra flux, so my mic and make sure that your your flux matches the core you're also using you don't want to mix fluxes at all bad chemical reactions happen if you mix fluxes because it will start eating your board basically. If you mix basically like no clean and clean and yeah, Ra what is ra stands for RA its rosin is what it is. I don't know what ra I don't know off the top of my head. Rosin activated Ra. Oh, there we go. And the great thing about ra flux is it's only activated when it's hot. So you can technically just leave it around forever. I've actually pulled out boards that were like 50 years old that had ra fluxes all over it. And guess what, though, you go in to fix the solder joint and you just heat it up and the flux re congeals into the liquid and like re does the join like ah fix now.
I would I will say you can generally leave the that flux around. But it does depend on your circuit. So if you have really high impedance nodes on your circuit, it will mess with those for sure. So be prepared, we're gonna get to that
flux cleaners next. So our home shop, definitely just use our a flux. I think there's actually some like Hackaday articles on making your own flux from like pine sap? Because that's what ra flux. It's rosin this tree sap? Yeah, more or less. Yeah, and apparently boiling 30
hours and add a little bit of essence of new in there. And you have a mute. Yeah.
Apparently works really well. Yeah, I think it was, um, apparently works really well. So other kinds of fluxes, you have no clean flux. And then you have water wash. And this other flavors of those kind, but those are the those are the three main types you have RA, water wash, and then no clean. There's different formulas in between there, just make sure whatever one you're let's say you have a core of water wash from Castor. Let's say it makes sure you get a a flux pen, for example. That's the same type of formula because you don't really want to start mixing because it also makes cleaning really hard. Now no clean is what like 70% of the industry uses nowadays is no clean flux, which is flux that it's like are a flux except that it doesn't leave as much residue around. And so typically, it won't affect the circuit as much been laying around in it but it's like our a flux where it's only really activated when you heat it up so it's not going to eat your board alive. Whereas water wash flux. If you leave that on your board it is going to eat all of the copper off that board. So I would say from a cleaning standpoint, water wash is awesome because it just just hose it off of the with your in your faucet with hot water and man it makes your board nice and clean. But it's harder to work with
water water wash, one of the nice things about it is because you have to wash it that means your boards are getting washed and they come out looking awesome. They look so good. After like if you want the most pristine, perfect look to your boards water wash is a great way to go.
Yeah, and so the difference is sure you can clean or a flood will get the cleaners in a bit. Sure you can clean are a flux off and it will look amazing. Usually you need a solvent though to clean ra off. Whereas water wash you can pretty much just get away with hot water and it will clean right off. So if the look of your board is important. Our water water wash style flux is the way to go. No Clean I would say anyone that's in a home shop or in their garage, just don't use no clean. It is just a pain in the butt to work with. It is own it was designed to reduce a process in manufacturing. That's what it was designed for. It was it's designed for mass production. So you don't have to wash boards in the end, which is greener for the environment blah blah blah like but the main thing was it doesn't have a process eliminates a process so it's cheaper to make stuff. But no clean is is great at that. That's what we use at macro fab for our SMT and then we use a wall gonna wash for the SMT side. And the trick with that though, you got to make sure you're if you're going to use no clean and wash the board, you have to be very, very careful, because a lot of no cleans. When you wash them, they become activated now at room temperature, it removes some of the chemical away and leaves other parts behind. It's like what it washing like removes like the organic side and leaves ionic side or something like that some chemical mumbo jumbo chemical engineer stuff that I don't understand. So if you water wash, no clean, you're gonna have to pretty much use this upon a fire or a more aggressive solvent. To do that correctly now backfat elbow grease or elbow grease, yuck. Basically, if you water wash, and no clean flux, you're gonna get these this like white crust around, and that cross is actually going to eat your board too. So home gamers just don't use no clean, it's just a pain in the butt.
Another thing also, back on sort of the visual side of things, if you use no clean typically after it's been activated it it's clear, but it is visible because it's glossy. So, you know, depending on the color of your board and the level of aesthetics that you're going for, it will leave blobs of glossiness around the things that you solder, and that it becomes way more apparent on matte colors. If you go with matte black say it still sticks out like a sore thumb. Yeah,
it's kind of like a glossy halo around the solder joint.
It looks like you put superglue on it. Well, yeah, that's
exactly what it is. Yeah, that's what it looks like.
Yeah. Yeah. So if you have, say, a red gloss. What is solder mask on your board? It's not as apparent is if you have like black matte, because it will show stick out. So if aesthetics aren't your thing? No clean is probably not the way to go.
Yeah, water wash is the way to go. If you want Sedex, though, I mean, water wash just results in amazing looking boards.
They're perfect at the end of the day, but it's a pain in the butt. Also something to be really careful with if you have to water wash your boards, the parts need to be able to go through a water wash process. And sometimes arch can't do that.
Yeah, make read your data sheets. And it's sometimes that she started mentioning like, Transformers just the manufacturers assumes you know that the wash clothes,
right, right, or potentiometers and things like that.
Yes, yeah. Anything that's got an opening? You don't really want to wash it. Yeah, like little microphones and things like that. Yep. Men's microphones. Yeah, those those data sheets typically will let you know, hey, don't watch these.
Right. But it is also a note somewhere on one of us 100 pages,
page 39. Footnote four.
Don't watch don't watch.
So yeah, I would say if you don't really care what your boards look like are a flux. Although for home gamer or a flux all the way or water wash if you want to step up your game in terms of like just process level data because the next step is cleaning. So if you need to clean your boards, you have water wash its water like hot water, boom done like distilled water. Honestly though, all I do is I just toss in my dishwasher clean the boards that works great no clean you need to if you go into clean no clean which is a funny way to say it but sometimes you have to clean no clean you need to go look at the datasheet for the for the no clean flux and see it's called saponify fire and you need to figure out what saponify Are they recommend to clean it with and sometimes I haven't sometimes you need to do rework and or sometimes you accidentally mix fluxes or something like that. And you need to go and clean a bunch of no clean off the board because or like someone spilled no clean all over the board. That happens. So you got to you got to go clean it. Now ra Flex is essentially SAP and everyone knows SAP is a pain in the butt to clean. So you need a solvent to clean that. I think Stephen just has a can of flux. Oh yeah, mg chemical flux remover. That sounds awesome.
This is expensive though. It's expensive. Yeah, this can I actually still have the price tag on it and I bought this years ago it was 15 bucks for what 400 gram can have this stuff but it even says it right on the front dissolves most types of flux including Ionic and non ionic residues. So that would clean no clean this would clean no clean right? Yeah, well, this would clean no clean after you've got no clean wet. Yeah, so this stuff is awesome. Use this with an ESD brush and You can get rid of most everything on on that board. It just powers through. Yeah.
Rubbing alcohol, high percentage rubbing alcohol. So like 90% Plus will clean Ra. Anything under 90 percents not really worth the effort of cleaning like 70% will just not clean it.
If you can get your hands on lab grade denatured alcohol 200, which is like that's like the top level stuff, get a little tray, put your board in it and let your board soak and and then use a little brush to get rid of. And
if you can't get that, go to your local liquor store and get Everclear Everclear real closest thing, right? That is really cool. That is basically a drinkable version of that. Yeah, it
doesn't it doesn't have the additives that make it taste like crap. It just already tastes like crap. Or it tastes like crap. Yep.
Everclear is also really really good at at at cleaning off ra flux. Because it has enough percentage like vodka vodka does not clean boards. By the way.
Vodka. Vodka is 30% water. So 40% water, it's 640 I thought I thought vodka was 70% think it's 60% Yeah, okay. I'm sure that there's some rules and regulations but not particularly good. Yeah.
Yeah. Oh, from chat engineer, Bob says MGM also cleans plastic beware. Also cleans plastic. Isn't that a good thing?
Well, maybe he's meaning eats plastic.
Yes, yes.
Yeah, this stuff I don't know if this stuff is good. The thing is, I've bought one cannabis my entire life. And so it's lasted me a long time.
Yeah, I use I have I have 95% rubbing alcohol. So that's why I use the clean ra flux. If I clean it, most of time I'm like, I'm gonna stuffed it into an enclosure I'm never going to see it ever again. So don't clean it.
I had a I had a some some stuff I bought a while back where somebody had gone in and done repairs on this one product. And there was something like eight PCBs in this product and they were all big PCBs and they went in and they used ra flux and it was goopy all over the place and it was gross they it was like a RadioShack repair job kind of thing. I went over to Target and Target had 95% alcohol on sale I bought the entire shelf worth of alcohol and I filled a bin like a big bin full of it I just dumped all the boards in them and went to bed woke up in the morning pulled them out and there was no RA and you know what's funny if fired up in to work perfectly so
so that's on why if you're using let's say ra flux and say no clean well no no cleaning to so let's say you use an RA no clean why would you want to clean it because we know what you want to clean no water wash you need to clean water wash because it is it is acidic at room temperature so it is just going to eat your board alive. Right right. So why would you want to wash something that is activated only when heated up?
Well I can I can tell you specifically from my industry we we design analog circuits that have really really high impedance nodes that are highly affected by parasitic stuff on the board effectively. So we have some boards where like constant current forces interface directly with capacitors and things like that, and we're trying to get linear ramps and if there's any parasitic elements due to flux on the board, then that ramp is not linear anymore and you start to get curves in your in your waves and things and flux is the number one thing that that causes that. So anytime you we do modifications to a board you know like you guys probably seen it before if you put an iron down on on flux then it like boils and splatters all over the place right? You Do you do any amount of rework on any of these boards, you have to clean them because you don't know where those flecks of solder residue are going to spray out on to so we clean even no clean or RA we don't use our work but if I did, I would still clean it just to make sure on on those kinds of circuits.
Yeah, it reduces your your we've talked about on the podcast previously voltage clearances and clearances and creepage creepage it so flux reduces that. So if you have high voltage lines you definitely want to especially if you're like right on the edge of the tolerance of like you know you need like 100 mil spacing, you know in air while that flex is going through Reduce that a little bit. So that's something you got to pay attention to. So that's why you would clean RA or no clean in that regard. Usually, though, you're talking to your manufacturer, they'll let you know what they're using. And you can figure out if that's a problem or not with your product or not.
Right, right.
Most digital stuff doesn't really care about the frequencies of now high frequency RF stuff. Yes, for sure. I think they actually make special no clean flux, that stuff that's like less susceptible to inducing that kind of stuff. I haven't actually built anything with that. But I pretty sure I've seen that in the catalog somewhere.
Yeah, it's when it comes to visual stuff. It ends up being a bit more frequently means.
I mean, yeah, you have your edges. That's all you care about.
Yeah, you don't want to smear those edges.
No. See, is that all we have time? Oh,
I got it. I got I have a funny tangent here. This is this is related to the digital side of things. I met someone the other day, it was freaking great. I love this. I'm going to use this forever. Now. This person was talking about their love of analog circuitry, but also the respect for digital circuitry. And they said that they live in the space between zero and one. And I love that that's so great. So that's that's my response to Parker there when Barker's like, you know, pull, pull it high, pull it to one. Live in this space between zero and
think it's my favorite thing I've ever said on this podcast, pull it
to one of the one.
Opponent high or whatever. Yeah, yeah, I
think that's my favorite thing. I've
I've not been the stupidest thing I've ever said. It's true, though. Is true. Yeah, doesn't mean it's stupid. not stupid, though. Okay, so what's cleaner? Think we covered all the bases on flux cleaner. But on the other side is cleaning your solder tips, especially this is very important with lead free, gets hotter temperatures more oxidization all that good stuff or bad stuff, I guess. Whereas let I've actually never really besides a RadioShack iron never really worn out a leaded solder tip before? I guess it could happen. I've never really had that problem before. Whereas led led free I like go through like, once a year or so.
Yeah, I mean, it just depends on on frequency. But yeah, let with lead free, you're talking about quite a bit hotter temperatures. And actually, that's that's something we didn't necessarily mentioned before. We said like leaded solder is somewhat easy mode. I think what I use there, but that's that's the thing about like, if you're a hobbyist and you're getting started with lead free, the thing is you their skills involved with easing lead free that you don't have to apply with leaded solder. So you end up learning how to be quicker, and how to get in and get out and get the job done. And not just mess around with what you're doing. And the thing about lead free solder is there's a lot more mistakes you can make with lead free solder than you can make with leaded, it's easier to get webbing, it's easier to get bridging, it's easier to get just a whole lot of these issues. And a lot of that has to do with how good the tip is on your iron. And you know how clean you're keeping
it how clean it is. Yeah. I don't think I have a specific brand I use of tip cleaner though. It's basically like a soup.
I think I'm gonna paste.
Yeah, it's like a gritty flux is what it ends up being. This is probably something else that's in it. But it's, it's a it's something that will rip the oxidization off your tip and coats it with basically pure tin is what it was doing. There's probably other ones out there that do different things, but that's just my experience using them. I've used a couple of different brands, but just by a reputable brand, I think haco Maxim caster thermal tronics has a their own thing too.
It's you know, those little those little discs that
it's a little disc Yep, just make sure you buy a reputable brand like I think mg chemical makes one don't buy a Rando one because who knows it might have led in it
and then you know what I actually do with those things. I use double sided tape and I stick them to my soldering iron so I always know where they're at. I'm sorry, not the iron I stick and
say like how would it bend into the
Yeah, it's like trying to lick your ear right? Like yeah, I just double sided tape them to the side of my, my soldering base and it's always there if I need it. If if I noticed that I'm soldering poorly just give it The stab?
Yep. Yeah. And that's a consumable, you will go through that. It's always good to clean the tip when you're done for the day too. So before you turn off the iron, dunk it in there, clean it up and then turn it off with just a big ol blob a tip cleaner on it.
So okay, so that leads to two things. One One thing I've seen people do I've even done this myself way back in the day and I learned the hard way it may seem appropriate don't take a file to the end of your soldering tips and try to like scrape off oxidation or anything like that it'll work but you're going to destroy your your tip so don't don't use a file or grinder or anything. You want to you want to chemically clean the tip not mechanically clean it. Yes, yes, yes. So yeah, don't like take a knife and try to scrape off oxidation or anything like that. Now
before this podcast I was like looking up different brands of tip cleaner and I found one that's called tip resurrection cream. This is an amazing translation error.
I was about to say like that just sounds like translation but ya know that's that's incredible. Yeah, yeah.
But you just said no mechanical cleaning but there is a weird mechanical clean well, okay sponge thing.
Right right. And that was actually the second thing is I wouldn't know as well okay, so that you're right that is I guess a mechanical way but it's a very gentle mechanical cleaning. So keeping that brass loofa or whatever that would I don't even know what those are called. Looks bunch things secure.
Like they're like oh scouring pads Gower pad that's that's the word. It's like Scotch don't buys those there. They make specific ones for soldering, which is a lot softer brass. Yeah, get those
well and so Parker had mentioned you know, a dip your dip your tip in the in the tip cleaner before the end of the day, yet dip it in there and then give it a couple of whites on one of those. Brass? Whatever you call them. I don't even know what they're called. Everyone knows what they are. Yeah, and that yeah, give it a couple of wipes on that before putting up from the end of the day.
And then so some soldering stations come with sponges. And I know some like of our workers will use sponges. I don't don't use a sponge, though.
Oh, like a wet sponge. Yeah, they, those come in like the cheapest of cheap kits always come with a little sponge.
But even like high end like Hakoda and stuff. I'll have a space for him. I throw those right away because I don't just use the breastbone. There's no reason to really, maybe there is and we're just not
privy to that information when I first started soldering
iron. I didn't use when I was first started. But that was till I found the brass
thing. Right, right. Yeah, because I went online. I was like, how to solder because my, you know, my, my parents didn't know how to solder and I didn't know anyone who knew. So I went online and I was like, how do you solder and it was like, you very much need a wet sponge and you need all this other stuff. So I started doing that. And then as soon as I found the brass thing, I was like,
sponges garbage sponge is is pretty hot garbage.
Yeah. And then you burn the snot out of it.
It's just that though it's I always think of it I want to this is the case. This is me just thinking about about it is the sponge is cold and wet. And your tip is hot. Super hot. There's gotta be some thermal shock on that tip when you hit that sponge, sure, or does it? Or is it just so hot instantly vaporizes and doesn't matter? I don't know
well, but but I mean the the water has to take energy away from the edge
has enough to cause a thermal shock in the alloy that the tips made out of.
I suppose if you just let it sit on the sponge then yeah, it's going to
Yeah. But yeah, I like what time I was soldering is back in college. I was soldering in my garage. And I was really lazy and the sponge was dried out and I poured a little beer in there
get a little bit of multiquip cleaner did not smell well though. No, I'm sure I'm sure burning here is not great. Because I mean there's still a good bit of sugar leftover so oh yeah, that's not good.
No. That's my little story on on. Sponges don't use any lazy Parker just very lazy because I couldn't walk like 30 feet and just got the sponge wet. Use the press bunches for dip clean. Now I saw I saw a very interesting thing last week. That thermal tronics makes an autumn a bunch of other companies make this too but they make an automatic brush cleaner, which is basically a spinning brass brush like for Like a wire brush that you would put on the end of your drill, but it's like in a box, so you can stick your tip in there and then it will aggressively brush the tip clean. Hmm,
yeah, that might be that might be one version of mechanical cleaning that I would be like yeah, thumbs up on, you know, yeah,
I actually kind of really want to try that. See that machine actually works really well.
Actually, you know, Okay, another thing if you have like a steel bristle brush don't use that on your soldering iron. Now the brass Yeah, it's got to be soft, right. I'm trying to look it up. What is that thing called? Like, on Google? It's like brass solder cleaner. brass wire sponge is what they're calling it. Okay, so yeah, brass punch is what we've been saying. Brass punch. Yeah. But it's not a sponge. No, because
it doesn't hold water at all. Right?
It looks it looks like one of those those pads Gaussian cleaning.
Yeah scouring pad for like cleaning. Yeah, but it's not as as even a brass scouring Pat pad that you use for a pan is more aggressive than what this thing is. Because these things like fall apart the moment you like, touch them.
Okay, so that brings up a, that brings up a good point, if you solder with any kind of frequency, by like a whole bag full of these things. Because you'll go through them really quickly, especially Okay, the motion isn't necessarily to just jam your soldering iron into this thing. Because all you're gonna do is compact all the brass into a big ol wad of brass and old solder and then it's worthless. And then it's just like, why are you even using this thing you want to it? It's not an aggressive clean, you swipe across that you do get the tip in there and swipe it. It's not like a jabbing motion, because then we'll just absolutely destroy the little bed but even with a more gentle swiping motion, these things do go bad, but they're cheap. Replace them often. Yep. Okay,
then one last piece of supplies. I think so.
Yeah.
So what would you have something else with with tip or you have anything else with Tip resurrection cream to talk about?
No, I need to buy some of that. Does it literally have it like on the can?
The added did I have to look it up? I find that link again?
Yeah, I could just see like a like a like a magazine adage. Like some kind of like really attractive soldering iron with like that. That tip cleaner next to it. It's like, maybe it's got it. Maybe it's tip resurrection cream.
totally gonna be the bike as Oh, for sure morning. I'm totally gonna make Photoshop that together. That's awesome.
It's absolutely gorgeous.
So solder wick is the last thing I put on the list. You have something else coming up after this. That's a small thing. Yeah, but so soldering week is the last consumable supply for soldering, I would say. And solder work is basically copper braid. And there's different widths, thicknesses. They also make it in different they're impregnated with different fluxes. So on that, this is what you use to kind of like help if you put too much solder down. Does how you get solder back off the board. And does it by basically heat and caliper like what's Calipari? Actually cannot pass
down to the capillary.
Capillary. That's it. I pronounced the middle part of the word strong to cap capillary action. Yeah. I need go to like school again. Just so speak correctly. No.
Um,
yeah, capillary action, is how it works. And actually, is it capillary action? Is that how wedding of solder works? Because basically, it's you're heating up the wick. And so that it you?
Well, it has boatloads of surface area for it to grip. Surface area. I think it's wedding and capillary action. Yeah, but also, although it's on the capillaries on the inside of a thing, right? Like an inside of a tube, whereas this would this is like a whole bunch of tubes that it's wetting the outside of it outside. I don't know, to be honest, I really don't know
what his wedding is the action of wedding that's the same mechanic as capillary. I don't know. I don't know. Anything. Actually, I will say I'm gonna take that back. It's, it's wedding. Basically, there's a lot of surface area of copper. So it's able to your wedding, the copper the alloy of solder away from the device.
Well, okay, so here's here's Wikipedia, you know, the source of all knowledge on the internet. Wedding is the ability of a liquid to maintain contact with The solid surface resulting from the intermolecular interactions when the two are brought together. So, I mean, it's basically how sticky it
was like so it is wedding then not capillary probably. Right, right. Right capillary is it's more of a function of the of dilution and the fluid moving through something to distribute itself more evenly. And it's more like how capillary works. I could be completely wrong. I think that's how it works.
You know, I don't know, because I guess if you think of like a strand, one copper strand within copper braid, if you start getting it wet, does the intermolecular intermolecular forces at the very like tip of the wave that's like growing on to it? Yeah. Is that what, like the heat? And the forces is that what causes it to kind of grip and continue to grow up the strand?
Well, it's definitely a heat. Yeah.
But is it a wedding wedding is the mechanism is one
is wedding the mechanism or is capillary action, the mechanism or that kind of both, or whatever anyways, so solder wick is a, it's a braid, and it's used to remove solder off off of boards off of joints, I use it a lot to remove, like, if I'm dragged soldering on a QFN. Or up, if you have a bridge that you just can't get the tip to wipe it away. You just put that little braid there and suck it away. I by the flux LIS version is what I buy, because generally, it's a lot cheaper. And you can just add your own flux to it. Whereas you can buy it if you if you know you're only going to use ra flux. Just get the RA flux. It's not awake, then it's faster. Yeah, it's faster, all that stuff. But if you're like me, and you still use some other, like, I sometimes work on no clean boards, and sometimes I work on water washboards. Get the get the flux lowest version. But you have to use flux with him that there's no way he's going to work without flux.
But yeah, you'll actually damage things if you don't use flux.
Yeah. And you will be able to just and you just use it with your iron and you're able to basically sucks otter athletes, I actually use a lot for desoldering thermal and stuff like, like to clear out the holes. A lot of people like you will have like little vacuum pump and stuff. And just solder wick good solder work and a hot iron with a big chisel tip will do the same job, it'd be, in my opinion, way less frustrating.
Well, and it's more gentle. Yeah, the vacuum is a is a pretty violent event all at once. And if you don't have the solder melted properly, you can actually cause damage to the pads. And so on top of that, a one of the so I also use flux LIS solder wick, because it allows you to choose what flux and then you can have it be compatible with what you're using on the rest of your board, which is nice. What I tend to do is I will just get a little like dish or something like that, and I'll squirt a chunk of flux into there. And then you can just continuously dip more wick into it, you get the wick is great, because it does exactly that it wicks a bunch of the flux up, and then you can go in and use it wherever you need to. Which as a somewhat of a side note, like if you're trying to make surface or if you're trying to do rework on surface mount stuff. And it's not simple like to padded components like resistors capacitors, say you're trying to do a T sub component or something like that. If you want it to look attractive, spend the time wick off the pads, the pads will all be flat, and when you go to install the next component, you can make it look as good as if it just came out of a reflow oven. If you if you hot air a part off and then try to put the new part on it. There's no way it's going on flat and it's going to look bulbous. That's the big thing is making a coplanar. Exactly. Yeah, yep. Now, do before we get to your last thing, I do want to rewind a bit to flux. Because you just said something we completely glossed over with Flux is delivery method or flux.
I think I mentioned pens. Yeah, so with Flux, because we talked about rosin core or flux core, I shouldn't say rosin core, that's our a flux, but But you have flux inside the core of your solder that using get a solder or get a flux pin. That's the same formula that you're using. And then if you can swing it, get the same flux in like a bottle format that's got like a needle applicator and usually you just buy like the flux and like a normal like bottle that you Like, that closes up, and you just get the applicator bottle separately, but it's like a little tiny squirt bottle that's got a little needle applicator. And that way you can, you can really put the flux down.
Right when you when your pins great when you
just thought, like, I'm gonna I just need a little dots on like, on a like a resistor, right? It's a little dab there. But sometimes you're like, oh, man, I gotta get this, like ginormous 144 pin TQ fee off.
Yeah, right, all
over the place. So at work
I do, I do virtually 100% of my soldering under a microscope. And so I don't use flux pens, because they get in the way of things in the bagel monster tips, I have exactly what you just said, I have a little bottle with a needle tip on it. And I can very accurately put flux only where I want it to go. And then I'm working right in that one little area. I think it's great to have both applicants with options for sure. Both options. And then if you are working with a big old double ra flux, get some acid brushes, and just use those to apply things. But most of the time, if you're working with RA flux and like big stuff, like you're gonna be big chisel tips and giant solder pads and things like that. You can get away with a acid brush where you just kind of paint it on and go to glob it on. Yeah. Oh, and the better the job.
We forgot to talk about don't use acid flux that you use for plumbers. Like
actually, we're so we mentioned that earlier. But something worth noting. Like, I think that that's enough of an issue that if you go to the aisle at like the big box, like the blue or the orange one, that the aisle that they have solder on, instead of just saying that type of flux because most people probably have no clue about it. They say for electronics or not for electronics. Yes, correct. Yeah. So the one that's not for electronics, that's acid core, because I
think if you had acid core are pretty sure the only way to really clean it is like making a paste of like
Baking Soda Baking soda. Yeah, yeah. You just have to like neutralize it. Right? Yeah, you'd
have to neutralize it before you cleaned it off. Yeah. So yeah, don't use don't use acid for
it. Yeah, it'll just it'll ruin anything you do. But if you're if you're soldering like a new water pipe in your in your basement,
I've fixed car radiators with that with that stuff. It's It's awesome, actually like Oh, it's great. I'll put this one is it's amazing what old stuff you can fix with just like a reel of acid course otter. Because even like steel parts you can like what them together and make them stick. Oh, the Flex is so aggressive on it. Yeah, it's not acid course or aggressive. It will make anything stick to anything. Yeah, it's kind of amazing. So I, you have solder pot as this leftover from last
week or so this is just a little Yeah, leftover because I realized we hadn't talked about this. And it's a little bit more nuanced because it depends on your application. There. It does have some bit of a consumable stuff. So this is a combination of last week and this week. So the the equipment I put on here is a solder pot. I think solder pots are actually extremely useful if you're dealing with through hole components. Or if you're doing like cable assemblies, or cable wire, whatever. It's really nice to have a solder pot next to you where you can dip, like a stripped wire in some flux, and then dip it right on a solder pot, you can tin the leads immediately. And that's great for things like stranded wires, where you just freshly stripped it, the wires are all bundled up together. And you want to keep them nice and together before you solder them into a PCB or whatever you're putting them into. So a solder pot is a nice thing to have around. And then the consumable for solder pot is solder. So So in addition to buying solder in reels, you can buy it in bars. And that's kind of why I wanted to put it on here because that's one other consumable that you might run into.
Don't use water wash flux when you're doing those cable assemblies.
Yeah, right. Right. You run into some problems. Yeah, basically,
because you're not gonna be able to wash all the water or all that flux out of your it's because it's going to wick up into the insulation. You're not gonna wash that out and then about, oh, three, four months later, you're gonna get a lot of corroded copper and that flux. Yeah. I never saw that a customer product, but I've seen that in inductors before. So that was interest that was very interesting. Figuring out what went wrong scenario.
Another another quick side note for solder pots. I've done this in the past at work fairly well. You can use solder pots for things other than solder. I found a soldering. Well, yes, but I found I found a product that went in a solder pot. That was a varnish remover. So we had some really fine wire. And you would heat this stuff up and you just dip it in and it would only eat the varnish and the mammal off off an magnet wire. Yep, yep. And he'd done. It did an amazing job on it. Yeah,
that'd be so awesome. Because that's the biggest problem with using magnet wire is removing that varnish or Nammo off.
Yeah, this stuff was nasty. We used it under a vent hood. So this is not stuff I would say use for hobby level stuff. You know, you can rely on good old sandpaper tricks or the exacto knife for hobby level stuff. But if you do if you are building enamel coated wire into a manufacturing process, consider a solder pot with some of this stuff in it. Just make sure the safety precautions are there to
imagine having a little pot of a highly volatile substance also heated up is it's
ready to go to town. You're ready to go to party. Yeah, this is the mecca of engineering podcasts where we could talk about solder for an hour straight. Yeah,
exactly. We have two other topics we're just gonna put off next week.
Yeah. Next week. Those are actually Speaking of next week, I will actually be down in Texas. So we're gonna have an in person. Podcast next week.
Oh, that's gonna be fun. Yeah,
it's got about that. It's been two years since we've had an in person.
Yeah, that was that July. I was up in Colorado. That
was yeah, that was 2019. Yep. So a little over two years. Yeah.
That's where I came up. I came up for vacation. And I'm like, oh, it's gonna be so nice and cool. In Colorado. No, it's same temperature. Yeah, it was the same temperature is Houston. Now in front of you. It's like the week before that was cool. And the week afterwards cool. I came up and it got hot.
You know, you know, it's funny. Let Okay, so last year, it snowed the first time in August. Up here like, it was a week snow when you like it didn't even really stick to the ground, but it snowed in August. The rule of thumb up here is you get the first snow by Halloween. Halloween is usually when the first snow hits. We are now halfway into November. It hasn't snowed. And it was 71 today. It's just it's super weird. I think it's colder in Texas than it is here. Yeah, it's
today got up to like 75 It was a nice day today.
Yeah, so it's around the same. I guess. It's wrong. Yeah, this this is strange. I've been here three and a half years. And and now I'm like, What's going on here? This is weird.
You're gonna get like eight feet in three days. Yeah,
I did. We did have a snow last year. That was I went out to shovel and it was above my waist. So
that means because because your street is like three feet lower. That street must have been like eight feet of
snow. It wasn't eight feet. But it was it was like
six feet. You'd be over your head in the street.
That that was one of those nights where like, I probably should have shoveled three times. But I was like, I'll just wait and do it all at once. I did. I was exhausted when I was done. Yeah. The funny funny story about that, like I my, my sister and her family were coming to visit us the next day. So I was like, I'm going to shovel the driveway going to shovel the sidewalk. The kids will have fun because it'll be a really bunch of snow in the front lawn. So what I'm going to do is I'm going to tell them hey, I'm shoveling all the snow into a pile in the street because no one was getting out. I'm going to knock the street I'm sorry like aside the house effectively in front. I'm going to shovel it all in a pile. So drive the car and you know get some speed and get into my driveway. They drove the car directly into the pile. I shoveled the entire driveway and the sidewalk and they drove the car straight into it and we just had to wait for it to melt because it was like really guys really?
You know that's what I would do. I try to climb it with my jeep. Well
Would your Jeep Yeah, you know you don't have a big old minivan with a bunch of guys. I wouldn't get stuck either. It's like oh my gosh, are you kidding me? I just I shoveled you guys a trap for your
so I think with that we'll end this podcast this week. So that was
my back and fat engineering podcast.
Don't get stuck in a pile of snow people.
Take it easy later.
This week Stephen and Parker were supposed to discuss bench equipment for development and testing but got distracted by talking about home-brewing beer.
What kind of soldering equipment should an engineer look at getting for their bench? Parker and Stephen start discussing equipment and supplies!
Ever have PCBs that solder just will not wet and solder to? You probably thought it was improper soldering technique but that was probably not it!