[HN Gopher] Soldering the Tek way
       ___________________________________________________________________
        
       Soldering the Tek way
        
       Author : zdw
       Score  : 187 points
       Date   : 2025-01-09 22:37 UTC (1 days ago)
        
 (HTM) web link (hackaday.com)
 (TXT) w3m dump (hackaday.com)
        
       | XorNot wrote:
       | Just yesterday I bought myself a set of pure copper tips off
       | Amazon.
       | 
       | People say they don't last, but I have had an incredible amount
       | of difficulty getting regular tips tinned and conducting heat
       | efficiently.
       | 
       | No combination of tip tinner, flux or cleaner has ever fully
       | resolved it for me.
        
         | serviceberry wrote:
         | My best guess is that your soldering iron is running too hot,
         | or that you're using the wrong kind of solder. It's generally
         | not an issue.
        
         | Workaccount2 wrote:
         | It's more likely that your iron is under powered for your
         | application, and frankly a copper tip will likely make the
         | problem even worse. There are three dimensions that impact heat
         | transfer (temperature being equal): Thermal mass of the tip,
         | thermal conductivity of the tip, and power transfer to the tip.
         | 
         | If your iron cannot support a regular tip, it's likely that it
         | cannot get enough power to the tip to sustain the heat being
         | pulled from it (copper will just expedite this). You can try a
         | beefier tip (or load up a tip with wet solder which can kinda
         | give the same effect) or you can get a higher power iron.
         | 
         | I've been soldering for 15 years with all manner of irons, I've
         | never needed a copper tip, but I often need more than your
         | standard hakko or weller. 400C on a the hakko is not at all
         | close to being equal to 400C on a Metcal for instance.
        
           | XorNot wrote:
           | When the tip is tinned effectively though, my Hakko works
           | fine. The problem is keeping it properly tinned is a damn
           | challenge: i.e. I think I wiped the whole thing on a sal
           | ammoniac block, then rosin flux, then put the whole tip into
           | a solder bath and got...a tiny spot on the tip which has
           | remained reliably tinned and is the one spot which works
           | well.
           | 
           | The symptoms are pretty obvious: even if the iron was
           | underpowered, melting a thin piece of solder wire should be
           | pretty much instant. My issue has just always been getting
           | the tip to a shiny solder finish with all the recommended
           | tools...just doesn't work once that iron layer oxidizes
           | initially.
           | 
           | EDIT: Although thinking about this now, actually the way you
           | get rid of mill-scale is with white vinegar so maybe that's
           | my actual answer: white vinegar for a couple hours, then
           | rosin flux and then into the solder bath. Hopefully won't
           | remove the entire iron coating on the tip since
           | otherwise...copper tips again.
        
             | joemi wrote:
             | It sounds like maybe either you're doing something wrong or
             | there's something wrong with your iron. I have a Hakko and
             | it works great, I have no issues with tinning the tip at
             | all, never had to do a vinegar soak or anything like that.
        
             | femto wrote:
             | I had a tip like this once. I ended up getting an old flat
             | blade screwdriver and running the sharpish edge of it up
             | and down the tip to remove the baked on crud, until I could
             | see the dull shine of the plating all around. I then tinned
             | the tip using flux bearing (electronics) solder and
             | repeated until all the dry bits on the tip had gone and the
             | tip was fully tinned. It seems to have been okay since then
             | (quite a number of years).
             | 
             | I wouldn't want to do the above too often and it's probably
             | not the recommended way, but I seem to have gotten away
             | with it by not being too rough with the screwdriver.
             | Potentially worth a try if the tip is a write off
             | otherwise.
             | 
             | Once it is tinned, clean and tin the tip before turning off
             | after every use (but you probably already know that).
        
             | Workaccount2 wrote:
             | What temperature do you have it set to?
        
         | relwin wrote:
         | Keeping a thin layer of solder on the tip when shutting down
         | helps keep the tip from oxidizing, especially if you solder
         | infrequently.
        
         | gazchop wrote:
         | You probably have a shitty soldering iron which can't deliver
         | heat consistently. Try grabbing a used Metcal PS900 or MX500 on
         | eBay. I have done zero maintenance or tinning on either of
         | mine. They just work. I do SMD and TH stuff and rework no
         | problems at all.
         | 
         | Literally everyone who gets one goes "oh so that's what
         | soldering is supposed to be like"
         | 
         | Also might be crap solder. Get some decent Felder or Multicore
         | stuff. Leaded is easier to work with and harmless if you wash
         | your hands and don't lick your PCBs. Silver bearing leaded from
         | Felder is what I tend to use. But it's about $70 a roll
         | 
         | Edit: I see that you have a Hakko. Buy genuine tips. Or replace
         | it with a different iron. The cheaper Hakkos are terrible.
        
           | Gracana wrote:
           | Replacing the entire soldering station would be quite an
           | overreaction to an issue with the tip.
        
             | gazchop wrote:
             | It really isn't. It's probably not just the tip.
        
       | ghayes wrote:
       | Curious if anyone has tips on lead-free soldering. I basically
       | always see in online forums "just use lead," but never any tips
       | on how to actually become capable on using lead-free solder. Esp.
       | as my son is around a lot, it seems prudent to stay lead-free,
       | even if you can generally handle lead safely. Thanks.
        
         | ryandamm wrote:
         | I'm hardly an expert, but when I switched to lead-free solder
         | (for the same reason, had a young kid around), the only change
         | that helped me was soldering at a significantly higher
         | temperature. The lead free stuff still doesn't behave quite as
         | well as the leaded stuff -- hey, lead is useful! -- but I do
         | feel a lot better about my garage. Though I did backslide when
         | I had a project that required about 500 manual solder
         | connections; after a few days of frustration I guiltily went
         | back to lead, briefly.
        
           | breckenedge wrote:
           | Ditto. I switched to lead-free for custom keyboards and it
           | didn't seem too terrible, just had to dial in the temperature
           | more closely to avoid damaging components.
        
         | IgorPartola wrote:
         | I use lead free solder and haven't had issues though admittedly
         | I have been soldering as an amateur for decades. You want flux
         | and higher temperature. That's about the only adjustments. It
         | goes without saying that you should use clean tips and a
         | quality iron.
        
         | sitharus wrote:
         | Leaded solder is not a big health risk for hobbyists as long as
         | you have proper fume extraction. Metallic lead is poorly
         | absorbed through the skin (it _is_ absorbed from what I can
         | find, but very very slowly), the major risk is from lead vapour
         | and at normal soldering temperatures that's very minimal.
         | 
         | However, lead free tin-silver-copper (SAC) solder is fairly
         | easy to work with. You need a hotter soldering iron at around
         | 300degC, and if soldering PCBs preheating the board to
         | 80-100degC may be needed for good results. It may also take a
         | bit longer for the solder to propagate flow and wet, since the
         | surface needs to be hotter.
         | 
         | If you're using additional flux or non-fluxed solder you'll
         | need to check it for compatibility, that should be on the data
         | sheet. Most fluxes are fine, but I've seen a couple that say
         | not to use with some lead free solder formulations.
         | 
         | The main downside to SAC lead free solder is the higher
         | temperature required which can overheat some components,
         | particularly capacitors and ICs in my experience. It's a case
         | of being careful to keep the heat duration as short as
         | possible.
         | 
         | Personally I went back to lead solder and manage my exposure
         | with ventilation and HEPA filters.
        
           | TheBigSalad wrote:
           | I've heard that the soldering temperatures aren't nearly
           | enough to make the lead a gas and the fumes from the flux are
           | what can kill you. I suppose the same advice applies in that
           | case, but is that accurate?
        
             | sitharus wrote:
             | Yes that's accurate for hobbyist work. There will be some
             | lead vapour, but at the temperatures used for soldering
             | we're talking a few atoms. The flux is much more of a risk,
             | and both are mitigated with proper fume extraction.
             | 
             | Lead does bioaccumulate so continual exposure to low levels
             | is dangerous, but unless you're soldering all day every day
             | it's not likely to be dangerous.
             | 
             | If you're a factory and have multiple wave soldering baths
             | operating it's a different story.
        
               | IgorPartola wrote:
               | Lead has a boiling point of 1749 degrees C. That is at
               | least 1200 degrees higher than your typical soldering
               | temperature. If you use a propane torch you'll almost
               | touch that temp.
        
               | sitharus wrote:
               | Correct, but all materials have a vapour pressure so
               | there will be a very small amount of lead vapour when
               | soldering. Based on lead's vapour pressure it's in the
               | range of a few atoms, I haven't done the math though.
               | 
               | I mentioned it for completeness because someone else
               | would if I didn't.
        
               | IgorPartola wrote:
               | Quick math shows that vapor pressure of lead at 500
               | degrees C is 1/7,600,000 of an atmosphere. I don't know
               | how to calculate the rate of sublimation but this does
               | seem pretty negligible.
        
               | Aldipower wrote:
               | Did you ever forgot a cup of water somewhere? It fumed
               | away after 2 weeks! All without boiling it. :-O Same
               | applies to lead, especially if you heat it to 360 C.
        
               | IgorPartola wrote:
               | I mean you can do an experiment: put a gram of lead onto
               | a hotplate at 360C, then weigh it after 2 weeks. I would
               | really love to see your results.
        
               | hooli_gan wrote:
               | Do you know how dangerous new vs old flux is? I'm using
               | some old Kanifol' from the USSR and get headaches while
               | soldering. Fume extraction would probably be a good idea,
               | but I solder no more than 4h a year
        
               | IgorPartola wrote:
               | There is a technique where you breathe out as you solder.
               | No idea if kanifol' is toxic or not but honestly if it
               | gives you headaches why not try another type? Or wear a
               | respirator?
        
               | hooli_gan wrote:
               | The answer is laziness
        
               | sitharus wrote:
               | It really depends on the flux, even modern fluxes have a
               | range of toxicity. The only way to know is to check the
               | MSDS.
               | 
               | I use Kanifol'/rosin flux as well and use a fume
               | extractor. Rosin flux is the most common for flux-cored
               | solder in my experience.
               | 
               | But a few times a year is unlikely to be an issue,
               | soldering health effects are in people who do it for
               | work.
        
             | jdietrich wrote:
             | Most electronics fluxes aren't particularly toxic, but
             | rosin is a sensitiser - repeated exposure will cause an
             | increasingly severe allergic reaction. Working in a well-
             | ventilated room is probably fine if you only solder
             | occasionally, but anyone who is soldering regularly should
             | be using a good fume extraction system.
             | 
             | https://www.hse.gov.uk/pubns/indg249.pdf
        
           | zrobotics wrote:
           | One thing I didn't see brought up in the sibling comments
           | about vapor is that the real hazard of using leaded solder is
           | small particles which can end up on clothing or your hands
           | and later ingested. It is definitely a hazard to be aware of,
           | you want to wash your hands after working with it and keep
           | your workspace cleanliness in mind.
           | 
           | For hobby work, I've switched to lead-free simply because
           | that's what 99% of the boards I work on we're originally
           | soldered with, but I still have some leaded solder around.
           | That being said, it can be used safely, I cast my own bullets
           | which generates a far larger amount of lead particulate and
           | my blood lead levels were not at all elevated when I had them
           | checked 2 years ago. But since it bioacumulates, you do want
           | to keep exposure in mind.
        
             | sitharus wrote:
             | Good point, I totally forgot that because cleaning my
             | workbench and hand washing after work is just second nature
             | to me now.
             | 
             | Metallic lead is dangerous if inhaled or ingested, but not
             | a big concern for momentary contact with your skin as
             | metal, especially given most modern solder is only 40%
             | lead.
             | 
             | Your body will remove a small amount of lead, so hobby
             | soldering is unlikely to cause long term problems.
        
               | TheSpiceIsLife wrote:
               | You can also take lipoic acid, methionine, and n-acetyl-
               | cysteine, to help the body remove bioaccumulated heavy
               | metals.
               | 
               | This is proven to work via hair-tissue mineral analysis
               | before starting therapy, during, and after.
        
           | BasilofBasiley wrote:
           | I cannot imagine anyone soldering with SAC at 300oC. Not even
           | leaded solder with pre-heating as merely an option. But
           | somehow those values crop up from time to time.
           | 
           | I'm not going to debate them though, I'll just dump my
           | values, it might help someone.
           | 
           | My job involves soldering at least once a week from through-
           | holes to SMDs(mostly), 1.6mm to 0.8mm pcb thickness, from
           | 1206 smd to 0402 (imperial) sizes. From flimsy 0402 resistors
           | to beefy 1cm2 all metal casing inductors from hell.
           | 
           | To do all this I use a JBC soldering station with C245 and
           | C210 tips. I also use a non-brand hot-air station for TSSOP
           | ICs with exposed pad on the underside for heat transfer.
           | Sometimes I use a hot-plate as well, and a reflow oven while
           | we're at it.
           | 
           | On the JBC:
           | 
           | For leaded solder: 350oC on both C245 and C210 tips. I do
           | increase it to +/- 360oC on occasion to solder near big
           | stubborn ground planes on the pcb. Less than that is
           | impossible without pre-heating because I can't afford to
           | spend more than a few seconds on each soldering op, both
           | because have other things to do and because I can't overheat
           | components. Overheating is also dependent on the _time_ you
           | spend on each component. Might bump it up to 380oC on those
           | inductors and switch the tips to beefier ones like the
           | chisels and the knives.
           | 
           | For unleaded SAC: 360oC to 380oC on those same tips, and I
           | might bump it up to 400oC again on those inductors.
           | 
           | On the hot-air station:
           | 
           | For leaded: 275oC
           | 
           | For SAC: 282oC
           | 
           | On the hotplate: 240oC for both SAC and leaded. (Mostly
           | repair work after pcbs come out of the oven.)
           | 
           | On the oven: It's a temperature curve and I only use leaded
           | solder paste. Peak at 240oC.
           | 
           | NOTE1: All the soldering wire I use is flux cored. I tend to
           | use extra flux a lot (Chipquik SMD291), even if it's not
           | really necessary. But on lead-free SAC it's always
           | obligatory.
           | 
           | NOTE2: We don't have any fancy setup where I work and it's
           | overall barely professional in my opinion. Pre-heating is not
           | used much if at all so, I don't have any temperature values
           | to share in that regard.
           | 
           | NOTE3: The SAC solder wire I use is Sn99Cu0,7Ag0,3 EVO11 from
           | CYNEL. I like the brand but I feel the need to try other
           | formulations for different use-cases so I can get away with
           | using lower temperatures on specific temperature sensitive
           | components. On leaded I don't feel that need at all.
        
             | sitharus wrote:
             | That is indeed a typo, it's supposed to be 400degC.
        
               | BasilofBasiley wrote:
               | Got it. Cheers.
        
               | oasisaimlessly wrote:
               | You can (/ should) edit your original comment.
        
             | stavros wrote:
             | I have my Pinecil set to 320 C and it works beautifully for
             | leaded solder. I momentarily bump it up to 400 for big
             | ground planes, but rarely.
        
               | BasilofBasiley wrote:
               | It's curious how you use such a big temperature range.
               | I've never used a pinecil despite having friends telling
               | me very good things about it, which picked my interest a
               | bit.
               | 
               | Can you tell us what exactly do you solder at 320oC and
               | what is the exact type of solder you use and/or Pb and Sn
               | percentages?
               | 
               | Also, is your pinecil calibrated? And which tips do you
               | use at that temperature?
               | 
               | Anecdotally, what usually happens to me at lower temps is
               | the tip and/or the solder wire _sticking_ a bit while I
               | 'm soldering which I take as a sign that the liquid
               | solder won't flow correctly and that I have to spend more
               | time giving it heat from tip, than I should.
        
               | stavros wrote:
               | I use 63/37 solder with a flux core. The Pinecil is
               | amazing, it holds heat really well and gets to 320 C in
               | eight seconds. I didn't calibrate my tip in boiling
               | water, and I don't remember which tip I use now, it's the
               | one that comes by default (B2?).
               | 
               | I only bump it up to 400 C because that was the default,
               | I never use it for more than two or three seconds so the
               | temperature hasn't mattered much. I haven't noticed
               | solder stick, it just sometimes fail to melt properly
               | with large ground planes, so that's when I bump the heat.
        
           | moffkalast wrote:
           | Yeah I've found that SAC solder typically doesn't contain
           | nearly enough flux to get the job done (just 2% at most,
           | seriously?!). Small joints like really tiny wires work great
           | at something like 370C so I can just touch it for a split
           | second and it's instantly done, for anything else it's
           | dripping into flux paste time and it works almost as good as
           | leaded used to. Would've been easier to streamline the
           | process if the rosin core was like 10% or 15% instead.
           | 
           | Not all types of flux work well though, my local store sells
           | something that has no labels but seems to be very aggressive
           | and works exceptionally well, the more common no clean types
           | don't do anything at all.
           | 
           | Tips are definitely eaten a lot faster than leaded, but it's
           | not exactly a huge expense when they're like a dollar or two
           | for a 10 pack on aliexpress.
        
         | rcxdude wrote:
         | The higher temperature is the main source of difficulty: it can
         | be harder to heat up a joint to the right temperature without
         | overheating the iron tip or the components. So it's mainly a
         | case of getting good thermal contact between the iron and the
         | joint, and having a powerful enough iron and the right size
         | tip.
         | 
         | (One trick that can be very helpful is pre-heating: e.g.
         | placing a board on a hot-plate at ~150C or so, or using a hot
         | air gun to do the same. This means the iron doesn't need to
         | heat a much. But of course this makes placing and holding the
         | components more difficult)
        
         | jwr wrote:
         | Use a higher temperature and plenty of flux (I like flux pens),
         | and you'll be fine.
         | 
         | Leaded isn't actually a significant health risk for you, so you
         | might as well go with that. It's not like you are going to
         | breathe in lead. It's a problem for the environment in general,
         | and you do not want to consume it, but it isn't that unsafe. A
         | bigger problem is that you should never use leaded solder to
         | repair boards that have been soldered with lead-free, which
         | means pretty much every board out there that has been
         | manufactured in the last 20-30 years or so.
        
           | giantg2 wrote:
           | I agree. The rosin/flux comprises the majority of the fumes.
           | It's still a good idea to have ventilation.
           | 
           | I have a setup in my garage with a vent fan connected to a
           | dryer vent and a rubber flexible hose I can put near the
           | solder station. I also hook it up to my 3D printer enclosure
           | if I'm doing ABS.
        
           | phaer wrote:
           | > A bigger problem is that you should never use leaded solder
           | to repair boards that have been soldered with lead-free,
           | which means pretty much every board out there that has been
           | manufactured in the last 20-30 years or so.
           | 
           | I am unlikely to every try this, but curious: Why is that,
           | what would happen?
        
             | jwr wrote:
             | It results in unreliable joints that will cause problems
             | over time.
        
               | Kirby64 wrote:
               | Source? If you're doing board repairs and adequately
               | clean the previous components then I see little reason
               | why adding leaded solder to the very small amount of
               | remaining lead free solder would be a problem. If you
               | have a full lead free joint and then add a bit of leaded
               | solder, sure... but how many people are doing board
               | repairs like that?
        
         | serviceberry wrote:
         | It's really OK. With modern formulations such as SAC305 and
         | with temperature-controlled stations, there's no real
         | difference, and no need to stick to lead.
         | 
         | I think the resistance to the idea has two roots. First,
         | there's a lot of old-timers who just didn't like the idea of
         | the government meddling with their hobby, so they go out of
         | their way to convince others to use leaded solder.
         | 
         | Second, the first years of the switch were painful. You needed
         | to upgrade some equipment, the early alloys were not performing
         | great, there were problems with tin whiskers (which aren't
         | specific to lead-free soldering, but were apparently happening
         | more commonly), etc. But these days are gone. The industry has
         | moved on.
        
           | giantg2 wrote:
           | I will say, you need to use high quality lead-free solder
           | when you could get away with decent lead solder. The cheaper
           | lead-free stuff has been junk in my experience.
        
             | marcus0x62 wrote:
             | Do you have any recommendations? I was soldering earlier
             | today and noticed a particular joint wasn't flowing well at
             | all. I looked over and had grabbed the lead-free solder
             | from my spool holder. All the other joints with my crappy
             | Radio Shack leaded solder were fine.
        
               | giantg2 wrote:
               | I don't. I have a roll of lead-free that works OK, but I
               | got it so long ago that I don't know. I think it's an
               | off-brand that doesn't even have a name on it, or the
               | sticker peeled off. It's still more temperature sensitive
               | than lead, but not bad. I think my better quality lead
               | roll is from them too. I wish I knew the name so I could
               | order more of each.
               | 
               | On a related note, I've had terrible luck with any of the
               | Chinese solders off of places like Temu or Banggood. Even
               | the lead ones were junky.
        
               | photon_rancher wrote:
               | Chipquik works fine. There's probably better stuff but it
               | is consistently good and doesn't seem to go bad (i can't
               | tell much performance stuff between a roll that's old
               | enough to have the label rubbed off and a brand new one).
        
               | Ccecil wrote:
               | With lead free use SAC305 with "no clean" flux (I prefer
               | the name "low solids"...since you still need to clean
               | it).
               | 
               | For leaded Kester44 is my favorite.
               | 
               | Set the iron temp to the datasheet of the solder...then
               | never touch it.
               | 
               | For larger pads use larger tips...a lot of people get
               | into trouble cranking things out of range.
        
           | jeffbee wrote:
           | The government did not meddle with the hobby, though. You,
           | hobbyist, can acquire and use as much lead as you want. You
           | can order an 4kg bar of 60/40 lead solder on the internet
           | right now. That's enough lead to measurably lower the IQ of
           | 15 million children, if optimally applied. Nobody will stop
           | you.
        
             | lazide wrote:
             | The hard part is holding them down while you apply it. They
             | squirm like crazy!
             | 
             | Also, you can buy pure lead in 1000 lb quantities (and
             | leaded solder) at places like [https://www.rotometals.com/]
             | with no paperwork.
        
         | indrora wrote:
         | As a child who was taught how to solder (Thanks Dad!) I can say
         | this: making the practice of post-solder handwashing just A
         | Thing does a lot to impart good practice.
         | 
         | if you're super paranoid, D-Lead hand soap is a fantastic
         | product: https://esca-tech.com/product/d-lead-hand-soap/ -- I
         | use it post-shooting to wash my hands of lead and residues from
         | firearms.
        
           | Taniwha wrote:
           | Yeah, I teach kids how to solder, we use unleaded solder, but
           | always insist they wash their hands after
        
         | amavect wrote:
         | I suggest practicing on perfboards, TH and SMT. Chipquik has
         | boards for about $2 each. Compare different solders (SAC305,
         | K100LD, SN100C), temperatures, pad sizes, fluxes, etc.
        
         | throwup238 wrote:
         | Just use Metcal fixed induction soldering irons. I just saw a
         | power supply for an MX-500 for $100 on eBay and there is the
         | hobbyist level PS-900 on sale new for under $300 on Amazon
         | right now (which works just as well but might not last 30 years
         | like an MX-500). Thermaltronics was started by some Metcal
         | engineers after their patents expired so they're a cheaper
         | source of tips but I haven't looked at their power supplies
         | recently.
         | 
         | Unlike wellers and other soldering irons they don't use a PID
         | loop. They exploit the curry effect of the alloys their tips
         | are made of and pump 2.6 MHz RF into the handle which keeps the
         | tip heated the entire time with zero delay, even when
         | contacting huge copper pours. The downside is that you have to
         | change the (expensive) tips to change the temperature, but the
         | upside is that it's capable of delivering much more heat. Since
         | the iron is capable of heating so fast, temperature control
         | doesn't really matter because it can melt the solder long
         | before damaging nearby chips.
         | 
         | If you're not using a solder oven, that's the best option. It's
         | expensive but it'll make a night and day difference to your
         | soldering work. I've got a Metcal that's almost 25 years old
         | that still runs like a champ, is compatible with tips sold by
         | Metcal and Thermaltronics, heats better than any soldering iron
         | I've used since, and is easily repairable if it breaks.
        
           | kevin_thibedeau wrote:
           | The MX-500s have a design misfeature where power is
           | constantly on internally. The switch only controls the output
           | driver to the handpiece. Put these on a switched circuit for
           | part time hobbyist use.
        
           | jdietrich wrote:
           | I don't want to start a holy war, but the JBC system with
           | integrated cartridge tips is at least comparable to Metcal
           | for high thermal mass joints and (IMO) superior for very fine
           | SMD work. The JBC system has the advantage of allowing one-
           | handed tip changes while the tip is still hot. It's also very
           | affordable to get in the door, thanks to the proliferation of
           | cheap Chinese stations that are fully compatible with JBC
           | tips. I do agree that the traditional style of iron with a
           | separate heater cartridge and tip is obsolete.
           | 
           | https://www.aliexpress.com/item/1005006568050453.html
        
           | opwieurposiu wrote:
           | Metcal inductive irons are so much better then resistive, use
           | one once and you will understand.
           | 
           | I pugged my Metcal into a power meter the other day. The
           | instant you the tip touches copper, the power jumps from ~4W
           | to ~40W. The power goes back down as soon as the solder
           | melts.
           | 
           | If you can not find good deal on a Metcal, JBC irons are ok.
           | Probably 80% as good soldering experience and often have a
           | better (shorter) handpiece.
        
             | Kirby64 wrote:
             | The same responsiveness happens with a JBC iron in my
             | experience. Temp hardly overshoots, and you can punch all
             | 120W into a ground plane if you get good enough contact
             | (and have a large enough tip). I've used both Metcal irons
             | and JBC irons, and I would agree with the other poster that
             | JBC is the better overall package.
             | 
             | Key benefits:
             | 
             | * JBC tips are cheaper, and clones are widely available
             | that are just as performant and even cheaper ($10/tip)
             | 
             | * JBC tips have adjustable temp; you can argue this isn't
             | useful, but if you typically solder leaded but need to
             | desolder something unleaded then this is a problem since
             | you need to bump temp to desolder properly.
             | 
             | * You mentioned this already, but handpieces are shorter
             | generally. In my opinion this makes a huge difference to
             | soldering experience, especially as I get shakier in my
             | older age.
        
             | SequoiaHope wrote:
             | I'd never used Metcal or JBC until recently. I've managed
             | 15 plus years of SMT work with Hakko style irons. I
             | recently got a new job, and the guy who manages our lab and
             | does our soldering previously did soldering for military
             | satellites for 20 years. He said he has something like
             | thirty satellites in orbit.
             | 
             | When I asked for a soldering station I could use in the
             | lab, I saw a lot of JBC machines around. I said "could I
             | get a JBC?". He said "oh the JBC is a Ferrari. I don't
             | think you need a Ferrari. I'll get you a Metcal. That's the
             | Toyota of soldering irons."
             | 
             | I can't comment on exactly what he means, but he seems very
             | experienced and has good things to say about JBC.
        
         | MarkMarine wrote:
         | Depends on the components. You need to get enough heat into the
         | joint that both sides are hot (pad and component) but not
         | enough that you burn up a sensitive part. The hack people use,
         | wetting the joint with solder by touching it to the iron can
         | lead to a cold joint. Don't do that.
         | 
         | Turn your iron up (I use 675) and ensure you're touching the
         | pad first, it's a much larger heat sync. Lean the tip of the
         | iron up to the component leg, give it a second and then feed
         | solder into the other side of the leg, letting the leg of the
         | component melt the solder and flood the joint. I use flux if
         | I'm really worried about the joint, the fluid transfers heat
         | better. There should be a clear fillet arcing between the pad
         | and leg of the component, solder should be wet 100% around the
         | pad and gracefully blend into the component leg. The joint
         | should not look sandy or dirty or have bad surface finish.
        
           | Hackbraten wrote:
           | > Turn your iron up (I use 675)
           | 
           | I felt a little puzzled about this but then it hit me that
           | you probably meant Fahrenheit.
           | 
           | To spare others the conversion: 675 degF is roughly equal to
           | 350 degC.
        
             | andrelaszlo wrote:
             | I solder very rarely and quite badly, but switching to non-
             | lead solder just made it impossible to get good joints. I
             | had to get a better iron, nothing fancy but with higher
             | effect, meaning I can get to a higher temperature faster
             | without turning the whole PCB into mush.
        
           | ahartmetz wrote:
           | Lead-free solder will have a dull surface even on a good
           | joint though, no? IMO worth mentioning. Not grainy or with
           | visible "fault lines", but dull.
        
             | MarkMarine wrote:
             | yes, dull, but not rough or grainy that is exactly correct.
             | It should be uniform, no grains or chunks, no crystal
             | structure, no boundaries but smooth.
        
         | userbinator wrote:
         | Don't forget that many of us grew up in an era when leaded
         | gasoline was widely used, and if anything the population today
         | does not seem any smarter, so whatever effects leaded solder
         | has is going to be miniscule in comparison.
        
         | photon_rancher wrote:
         | 1) board preheat. In a pinch, heat gun or old hairdryer. But
         | ideally get a cheap ceramic one off amazon or something.
         | Typically set it to 75C for delicate components. For sturdy
         | boards i start there and if that still sucks you can usually go
         | up to ~150C. Usually its the heating element or air temp not
         | the board temp.
         | 
         | 2) Flux and thin solder. Solder should contain flux too. Use
         | solder paste whenever possible and keep it refrigerated when
         | not in use as it dries out
         | 
         | 3) you need a high wattage iron and usually a thicker tip with
         | more heat capacity. A slightly higher temp helps a little, but
         | the wattage helps it stay a consistent temperature from the
         | start to end of the joint.
         | 
         | 4) when designing boards use ENIG and not HASL
         | 
         | 5) remove any old solder before attempting to add more to a
         | joint (older than a day or two).
         | 
         | 6) sometimes an air gun on a arm helps too on thick copper
         | 
         | 7) get really good lighting with a mix of diffise and
         | directional sources. Brighter than you'd think
        
         | randunel wrote:
         | Don't equate solder to (liquid) metal touching other metal.
         | Soldering is a chemical reaction between metals, and it needs a
         | pretty high temperature for that to occur. The solder simply
         | touching the other metals isn't enough, those are commonly
         | called cold joints, because the chemical reaction didn't
         | happen, only the mechanical melting and freezing did.
        
         | mystified5016 wrote:
         | I say this as someone who has been soldering their entire life,
         | but lead-free is fine. The differences between leaded and lead
         | free are minimal these days.
         | 
         | The best way I can describe lead-free solder is like using some
         | old and really crappy leaded solder. It can get kinda gummy and
         | ugly, but usually only when you touch a joint for the tenth
         | time.
         | 
         | The way to make lead free solder flow and work like leaded is
         | simple: flux. Flux pens are alright, but your world will be
         | forever changed by gel flux in a syringe. Clean up with rubbing
         | alcohol and a toothbrush or paper towel.
         | 
         | Modern solder alloys are pretty good. Just don't buy the
         | cheapest thing you can find. Always, _always_ get your solder
         | from a good manufacturer like MG chemicals. Also buy fluxed
         | (not no-clean) solder wick from those guys.
         | 
         | I used to be in the "just use lead" camp, but there's really no
         | benefit. I've been exposed to far more than enough lead in my
         | career. Lead-free is totally fine.
         | 
         | Some people fret about solder whiskers, but I'm unconvinced
         | that this is a real problem worth discussing. It seems to be
         | myth more than a practical problem that anyone but NASA should
         | care about.
         | 
         | Just use good lead-free. It's only trivially worse than leaded.
         | It's fine.
        
       | theogravity wrote:
       | That was extremely informative for such an old set of videos.
        
         | moffkalast wrote:
         | The first time I've heard of vacuum desoldering, so simple and
         | yet looks like magic compared to struggling with wicks. I have
         | gotta get myself one of those spring loaded plunger things.
        
       | jakedata wrote:
       | I learned to solder electronics using my father's giant Weller
       | soldering gun. 40 years later I was visiting and had to repair a
       | tiny connection on an electronic candle. I felt like Captain
       | Caveman wielding that giant humming pistol with the lightbulb
       | illuminating the work but by cracky I could still do fine work
       | with that monster tool.
       | 
       | This was the longest video I have watched on Youtube in ages. The
       | lack of intrusive ads was refreshing.
        
       | brcmthrowaway wrote:
       | I would love to play around with electronics but I hate
       | soldering. I hate the toxic smell and fumes, I hate the small bit
       | of metal shards that seem to go everywhere. It's been 100 years
       | since electronics, why no soldering alternative to make
       | connections?!
        
         | giantg2 wrote:
         | Technically I think there are conductive glues, but they aren't
         | right for everything.
        
           | brcmthrowaway wrote:
           | Gamechanger!
        
         | sitharus wrote:
         | Soldering makes a metal-metal connection, with the flux
         | ensuring oxides are removed. This makes a very low resistance
         | connection, mechanically it's very strong, and it's easy to
         | automate. As a bonus it's also very easy to undo.
         | 
         | Other technologies like glues and crimping have their uses but
         | are less reliable, higher resistance, or difficult to automate.
         | 
         | This may change but there's little demand. Glues have lower
         | conductivity and are harder to remove, mechanical connectors
         | are bulky and not as strong.
        
           | brcmthrowaway wrote:
           | What about solder that has flux inside m?
        
             | sitharus wrote:
             | It's the same as applying flux separately, the flux is
             | displaced by the metal.
             | 
             | If you're applying fluxed solder directly there's not much
             | point applying separate flux to clean metal. Of course the
             | flux will boil off pretty quickly so you need to use extra
             | if you're doing something where the solder wire doesn't
             | directly touch the components, or if the metal is old or
             | previously soldered.
             | 
             | The only advantage to non-fluxed solder for most hobbyists
             | is being able to choose your flux, but for most of us rosin
             | is fine and fairly non-toxic.
        
         | s_m_t wrote:
         | Use a fume hood or extractor and really learn how to solder
         | properly. It sounds like you are either running your iron too
         | hot and/or you are trying to melt your solder on the iron and
         | pass it to the joint. The pros use a TON of flux because it
         | practically solves the oxidization issue and helps a lot with
         | spreading the heat to where you want it to go. Half of your
         | temperature issues can be solved by either preheating your
         | boards or spot heating with a hot air rework tool.
        
           | brcmthrowaway wrote:
           | I also hate flux. Also seems chemically dangerous and
           | horribly sticky.
        
             | s_m_t wrote:
             | You don't have to touch it or eat it ;)
        
             | ibash wrote:
             | Electronics is not for you
        
             | sitharus wrote:
             | Flux in flux cored solder is rosin, rosin is distilled from
             | pine sap and is a permitted food additive. It's as a glaze
             | on chewing gum and pharmaceuticals.
             | 
             | Rosin is also used on violin bows to increase friction, and
             | it's the white powder you'll see gymnasts and baseball
             | pitchers apply to their hands to improve grip.
             | 
             | Rosin vapour is a lung irritant, so avoid breathing it by
             | using a fume extractor, and for some people it can cause
             | contact dermatitis.
             | 
             | Yes it's horribly sticky, that's the worst part about it
             | really. Isopropyl alcohol will dissolve it.
        
         | petee wrote:
         | You could do wire wrapping like nasa still does; there will
         | definitely be a high quality tutorial somewhere. Or if building
         | a squashed bug circuit you could use crimps (with or w/o the
         | insulator to be pretty)
         | 
         | But besides breadboards you're kinda stuck with facilitating a
         | clean soldering setup, which is fairly easy - if you're really
         | worried build a gloved-box. I just wear a respirator and open a
         | window
        
       | flyingzucchini wrote:
       | "Sodder" - I never pronounced it like that. It was always "Sold-
       | er"
        
         | sitharus wrote:
         | Sodder is the common American pronunciation, most of the rest
         | of the world says solder.
        
           | moffkalast wrote:
           | Nah some of the rest of us say sodder too, solder sounds too
           | close to soldier when you've got an accent haha.
        
         | geor9e wrote:
         | Interesting. My experience is the opposite. Sodder, soddering
         | is the norm. Every lab, every tech at every company has said it
         | that way. I'm from the west coast USA if thats relevant. If I
         | ever heard someone say "sold-er" I probably dismissed it as
         | someone who only ever read the word, and was sounding it out
         | phonetically.
        
           | ziml77 wrote:
           | NJ here. Also say it without the "L".
        
       | cwalv wrote:
       | When I was in college I worked as an "electronics technician"
       | intern for a few months. We would work through 3-10 page mods to
       | update PCBs from one version to the next. We worked under a
       | scope, and sometimes routed magnet wire all the way across the
       | board, or even thru vias from one side to the other. It was
       | painstaking work; I had a coworker friend who was a true artist.
       | I never got that good at it, but I sometimes miss that kind of
       | work.
        
       | plasticbugs wrote:
       | This comprehensive film series from PACE is how I learned (and
       | lots of practice) https://www.youtube.com/watch?v=vIT4ra6Mo0s
        
       | Animats wrote:
       | Here's real soldering the Tektronix way.[1] This is the soldering
       | technique for Tektronix ceramic terminal strips, which had silver
       | fired into the surface of the ceramic. The solder used was 3%
       | silver. The innards of Tektronix scopes of that era are just
       | beautiful.
       | 
       | Tektronix was the first to make oscilloscopes where the screen
       | was calibrated, and you could measure voltage reasonably
       | accurately. Earlier scopes just let you see the general shape of
       | a waveform. So Tektronix had to develop components and techniques
       | to make electronics behave consistently, over a wide range of
       | temperature and humidity, in portable instruments.
       | 
       | [1] https://www.youtube.com/watch?v=RpB5JqGo1co
        
       | chiph wrote:
       | I attended a high-reliability soldering class while in the USAF.
       | The attention to detail needed for a perfect solder joint is
       | phenomenal. I had lots of good-looking joints get rejected for
       | reasons such as exposed copper and a joint that had a convex
       | surface.
       | 
       | There is a USAF Technical Order for this, issued by the Navy and
       | shared with the Marine Corps:
       | 
       | https://www.robins.af.mil/Portals/59/documents/technicalorde...
       | 
       | Cleaning the joint before and after was key. We used isopropyl
       | alcohol in a push-down dispenser bottle, and acid brushes where
       | we cut the bristles down to about 1/4" inch.
       | 
       | Another poster asked about lead-free solder, and the military is
       | using it now but has concerns over tin whiskers.
        
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