outstanding content and production quality! thank you James!

Great video! As a beginner this answered ALL of the questions I had about flux. I'll likely start with a paste as it seems easiest for tinning the iron. Thanks for the info!

I bought a few of the pen tip replacements and it's very handy to have!

Great! I was recommended lately I should use a different type of flux. I've learnt a lot. Thank you!

That was very informative. I don't know if you did this before, but I would like to see a similar comparison on the types of soldering stations (basic hand held up to hot air).

I was looking for this kind of info. Great vídeo!

THANK YOU SO MUCH! Ive been so confused on which type of flux to use and how to use it

Always love your videos! Been watching them obsessively :)

I've used cheap flux where it's conductive when cold. Gave me a lot of head scratching looking for the short

One thing I noticed that wasn't talked about, is how well solder sticks to metal using certain kinds of flux. I've had very mixed results with different kinds of flux. I've had some that's really sticky and amber in color and it works very well in getting solder to stick where I want. I've had this white paste kind of flux, that barely did anything. Hardly helped the solder stick to what I was soldering and mostly just evaporated. I've had much better luck with the amber sticky type of flux doing the job.

Wow so thorough! Amazing

Thank you! Great video.

Great use of optocouplers to isolate the high and low voltages

I have a flux pen with a combination of just about everything collected over about 20 years. Rosin, clean, no clean high and regular activity. I prefer rosin core lead solder though because it works good and I like the smell.

Nice, I picked up some of that MG Chemicals 835 liquid flux recently to try. Works really well but boy is it a pain to clean!

I'm a heavy user of the shown chipquick flux, but also have pens and liquid stuff but I pretty much never use them unless for rather special tasks.

thank you James for this informative video, i have learnt a lot from watching it

Very comprehensive! Thanks for sharing your knowledge.

IPA??? Beer? LOL I guess in the soldering world it's Isopropyl Alcohol. What I'm gathering from your video is that any flux will allow any solder to adhere perfectly fine. Cleaning is a no-brainer at least it should be. My project is replacing a micro-usb port on a GPS. The flux I'm using does not help melt the existing solder (which I think is Silver based). But if I'm using a generic 60/40 solder, what flux works best???? Nice video, thank you for the insight.

I have some Kester 186 flux that's easily ten years old and still works just fine. I think the shelf-life limits of most of these types of things is not something most people have to worry about. Maybe if you're working on a satellite or nuclear reactor control or something, otherwise don't overthink it.

Chipquick 291 is a decent flux, but it left a residue akin to maple syrup. I did not enjoy cleaning it

SMD291 was my favourite too. Now, not available in my country anymore. Only SMD291NL - which stands for No Lead. Any experience with it?

3:53 What is that desk vice called and where can I find one? Or is it a custom 3D print?

Hi, my macbook air 2011 is beeping three times. I want to check if the problem is coming from the RAM chips by soldering them. What soldering flux would be best to use?

My dad has a can of flux that's older than I am. It still works. The life expectancy may be a bit over stated.

Lots of good information. Helped me as a noob make some sense of the flux choices!!! Manufacturers are not helping are they!

Chip quick in a syringe is the best.

I only solder occasionally and use my kid’s left over violin string rosin (he doesn’t play anymore). I just dip the soldering iron tip in it or use a solution of it in IPA. Works actually pretty good.

I am very surprised that some clarified pine sap from the tree out front is a great working and smelling flux. I boiled it down to a thick paste and can thin it with IPA for brushing. Haven't spent a cent on flux for years.

Well because of you I learned that you need to tin the tip XD from this video that is.

You should probably take more time explaining what IPC is, and why you are using their recommendations. If you work with a supplier for solder, flux and cleaning approach, like Kester for example, the flux type in production is largely based on the electronic assembly soldering requirements (like leaded or lead-free solder). In short, if the production assembly work flow requires, SMT reflow soldering, with final hand wire soldering before cleaning, you will select the flux accordingly. Meaning the reflow solder paste flux, wire solder flux and rework flux (usually a liquid brush on) will be the same flux or compatible according to the manufacturer. If the production contract includes field return repair or analysis, then IPC rework procedures are usually adopted with modifications for repair and analysis, with the soldering processes specified which will include the type of flux used. Cleaning flux can be a challenge if you solder devices that can trap flux, like QFPs or BGAs. In specific instances the only way to completely clean the board is to use a heat controlled ultrasonic cleaner with the recommended cleaning fluid (solvent). After cleaning you have to wait until the cleaning solutions evaporates, this may take considerable time at room temperature, so what you will find is to speed up the process, especially after rework to re-introduce the assembly into the production work flow, is to dry the board(s) in an oven (not a reflow oven, a drying oven). Once, the board is dry and stabilized at room temperature can you then test. If the rework involves a BGA one of the first tasks is to x-ray inspect the solder joints. Once the board passes solder inspection, now you can introduce the reworked board into the testing work flow. If you are assembling prototypes for a customer, I would recommend using a very nice looking pad copper plating like immersion gold (unless the contract specifies the plating) and then use an organic flux solder paste and wire, best to use eutectic tin-lead. The organic, water soluble flux, does an excellent job of removing oxidation, and will help migrate the solder completely onto the pad even if the footprint is small (high density), which means the applied paste volume is minimized. Yes you have to clean the boards at elevated temperatures (which is not unusual) in an ultrasonic cleaner, or in a board washer when in production. Or you can just heat up some distilled water to rinse the board if you don't have access to the production line equipment. After rinsing and inspecting that all of the flux is removed, dry the board in an oven, let cool, then test. I find the senior IPC soldering certified assembly technicians for hand wire soldering where you will add additional flux before soldering, usually choose liquid flux as a first choice, and then consider a tack flux if the liquid flux is not viscous enough.

what is the gel made of? (besides the rosin etc)

Wow... had to stop the video to say I really enjoy that intro. Real retro vibes, but concise. Nice!

I need flux for high heat, any suggestions??

It used to be so easy!!! Kester 44!!!

My kid is doing eng at well known uni. They did not introduce flux in elec eng units involving soldering. This is how issues start ! DOH !

How much flux do I need. Ok apply enough to cover the entire area if you can get to the door and not need a scuba kit you need more.

i searched for a video like this since i got my first soldering iron, so i bought my frist random flux wich is like organic ( its like very easy to dissolve hard to clean up) and organic i mean not too much poisonous,im glad with my purchase and i still wanted to watch the video since im not experienced in the art of soldering too much.

would be GREAT if you left links to the products you mentioned. Thanks for the great information!

how do you dispose of FLUX

Just a comment on smells to think about…. You must have particles of that substance inside your Nose…. to smell it…. Think on that next time you smell a ….. Good info

Can I use tinning flux in place of rosin flux?

Wife said the Chipquik smells like celery

no flux given

7:41

my favorite type of flux is white petroleum jelly

I insist that we must say "soldering under flux" instead of "soldering with flux".

If you use flux as an air freshener….. maybe seek help?

Nobody seems to talk about how sticky this stuff is. It gets everywhere.