Solder and flux advice.

tokyoracer

(Not actually from Tokyo).
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Hi chaps.

We all know that these machines are not getting any older, hell most of my "tat" is older than me so it makes sense for the owner to be somewhat knowledgeable in keeping these beasts alive rather than risk damage in transit and the costs/time involved if one could do the job themselves.

I'm aware many here do ALOT of repairs, it's something I've been meaning to get into myself so I can atleast do some more novice jobs (hopefully onto more amateur work as I get into it). I've had experience with basic Antex 25w irons but these seem more for super basic work like CR type battery replacements and perhaps cable making.

Just so you know, I now have a Weller PS-3D with a 45W iron. It's "temperature controlled", though temperature is dictated by the tip you choose. Hopefully this is a decent start for moderate repair work (it certainly feels alot nicer than any other I've used thus far)...
I'm already well up on pumps and solder braid, I just not sure about the following;

- What kind of temperature and tip type should I use for what jobs? My temperature choices are: 260, 315, 370, 430 and 480 centigrade.

- What kind of solder should I use? I'm looking at 63/37 0.3mm flux core solder currently. Is there a brand that I should look for or another type entirely?

- What kind of flux should I use? Paste or liquid? Should I use one of them bottles with a choice of needle nozzles? Again, does it matter what brand it is?

Apologies to bombard with questions. It just seems right to start doing my own more repairs as I finally got a decent station to attempt them with, and I want to do it right like the gurus here. :)

Thanks in advance.

P.S. I have a A4 PDF page on the tips for my iron. Let me know if it's needed for the correct advice and I'll upload it for reference.
 
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for me temperature isnt just dictated by tip type,but the work your on as well

i dont look at temperature at all i eyeball it to what i need,simple

tips,again i only use about two types anyway,chisel or flat tip,so makes no odds,sometimes a curved tip,but not alot with that one

solder is also sometimes a personal preference alot of the stuff i work on is leaded,so i prefer it,normally around 0.5mm or less

flux,well...depends what im doing so i could be using either paste or liquid no clean


only thing i do do alot id leave solder on the tip before i turn it off,it seems to last alot longer
 
It really depends on the particular thing you are working with, but for retro stuff you'd probably want to stick with the 315 C and 370 C temperature tips. As a rule of thumb you don't want to stress old boards with high temperatures any more than is necessary. Of course soldering a big connector is different from a surface mounted resistor, sometimes you just need a higher temp in order to complete a joint within a reasonable time.

Any flux intended for electronics work will do the job. I use a Weller paste type for big components and a "no-clean" gel flux from a syringe for small stuff. 63/37 or 60/40 solder are both fine, although you probably want at least two thicknesses, fine and medium (so in addition to the 0.3 mm you already have, maybe 0.8 mm).

Also, most importantly, practice a lot with dead boards: try to desolder components without damaging anything, solder the components back, and so on. That way you will get a feel for how things work with your equipment, and what the limitations are.
 
Imo a higher temperature setting often put less stress on the components than a lower one that you have to keep in contact with the joint for a prolonged period of time
 
With your equipment probably 370C would be a good generic temperature choice for small(er) components. As others have pointed out there is no universal setting as optimal heating depends on several factors: solder type, tip shape, flux, component size, joint is connected to ground plane, joint state. Solder of 60/40 with non-synthetic rosin flux core will be good in most situations, a thin (0.2mm and a thicker 0.5mm size is a good idea). Kester is a good brand for example, but almost any will do. Try to avoid the super cheap Chinese brands with questionable quality though.

For flux I like rosin based liquid type with a needle dispenser. But gel flux would be also useful in some situations, like when you want SMD components to stick to the pads for hot air soldering. Brand not so important as long as it's rosin based. Synthetic and water soluble and no clean fluxes are in general more difficult to work with so try to avoid them. In general flux always helps and you can never put too much, the only limit is the more flux you use the more cleanup you need after soldering.

If you use solder braid I HIGHLY recommend not to get the cheap Chinese stuff as their weting abilities as really bad. I use ChemWik from Chemtronix for many years and the difference is huge compared to the cheap stuff. Many people use the braid right off the spool, which I find to be a mistake as they are heating the whole spool with their iron so the weting ability is greatly reduced. I normally pre-cut the braid to smaller pieces for a much better effect.

Tip wise, chisel shaped tip is king in most situations, but you will need at least 3-5 different shapes and sizes for different joints. Conical needle tips are almost useless in generic soldering work. Key is keep the tip clean. Clean after EVERY joint. When I say clean, I not only mean to remove obvious goo and burned flux residue, but by REFRESHING the tip by removing a thin, oxidized outer layer, exposing fresh solder. Due to the high heat the tip oxidizes withing seconds after cleaning, so cleaning right before moving to the joint is the way.

And perhaps the biggest factor on soldering is how well you can make contact to the joint, if it's old and oxidized (for example due to capacitor leak) then you will have difficulty to heat it no matter what method or equipment you use. The biggest mistake in these situations that I've seen people make is to press down harder with the tip and/or jack up the temperature. This will almost always result to damage. Ideally only a very moderate pressure is needed to heat a joint. The correct approach is prepare the oxidized joint by first vigorously scrubbing with solvents like IPA (cleaning), adding plenty of flux, and even scraping gently until a little clean solder surface is exposed. For complete cleanup multiple passes with adding fresh solder and cleaning up (with braid) might be needed. Hot air works well too in these cases, but requires better skills and knowledge on temperatures.

Ultimately the best way to get answers to your questions is to try several different stuff, practice a lot on defunct boards and collect experience. Eventually you will settle to a set of tools and methods that works for you and feel comfortable with. Many of the old IPC training guides stress the principle of 'reactive soldering' which means that success MAINLY depends on you. Temperature, tip, flux etc.. rules are good for generic guidance, but YOU should always CONTINUOUSLY watch how the joint BEHAVES and adjust your tool or method accordingly. For this (stating the obvious but often ignored) you need to SEE precisely what's happening, so good magnification and good lighting conditions are absolutely essential.

I also wrote a extensive guide some time back for newbies (and some non-newbies ;) ) where the above is discussed more:

https://www.amibay.com/showthread.php?50780-A-short-tutorial-on-soldering-for-newbies

Good luck!
 
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yeah.... you know what I think that lot covers it ;)

Only difference is probably personal choice / technique and tool availability

Dont be fooled by labelling
I use a liquid no-clean flux (don't be fooled by the name EVERYTHING needs to be cleaned after work) and a thicker (sadly more corrosive) Flux Paste - (most certainly needs top notch cleaning)

IPA is your friend - you cannot use enough of it and you should try as well!
Also sponge swabs (like cue-tips / cotton buds but with sponge) and a fine (soft) toothbrush (electric is handy!) will be the tools to help!
(I might sound like a harbinger here, but ensure that all your tools are ESD safe - last thing one wants is damaged chips or corrupted firmware!)

I use various lead / non-leaded solders pending the application - usual gauges are 0.7mm 0.5mm 0.25mm and 0.15mm - again it comes down to the work involved.

Heat Range (comes down to your work)
Most SMD stuff you can flow about 240c (although my hot-air / solder station needs to be recalibrated) - Most general Through-hole is about 280c-320c - with a play-about when you get to ground planes versus tip size - some heavy gauge stuff wouldn't budge until it hit 420c! - again its important to note that with a 45watt iron, with a medium sized tip - while the device might be set to 420c its unlikely ever to attain that on a large ground plane - Now that I mention that, one needs to be mindful of thermal shock of components when you pass the 320c barrier - especially if there are SMD based IC components.

In closing
But all of the above, is just practical skill you will acquire as you go along - one thing that I humbly suggest is to learn the circuit and circuity that you are working on and within. Develop fault find skills and diagnosis - assumption might get you by, but its important to know how to diagnose circuity problems when the common fix doesn't work. With that I would humbly suggest a you-tube channel RetroGameModz to start with =)
 
...only thing i do do alot id leave solder on the tip before i turn it off,it seems to last alot longer


Same here, and never, ever file your tip. Once you go through the iron clad, it's toast.

To be fair this is a good technique to prolong the life of your tips - however I actually use a specific tip-tinning compound that is nothing short of a miracle for bring dead tips back to life (not that they are expensive - I have about 20 un-used ones) - it only cost about £5 from eBay - I will try and dig up the brand / seller for you.
 
...only thing i do do alot id leave solder on the tip before i turn it off,it seems to last alot longer


Same here, and never, ever file your tip. Once you go through the iron clad, it's toast.

To be fair this is a good technique to prolong the life of your tips - however I actually use a specific tip-tinning compound that is nothing short of a miracle for bring dead tips back to life (not that they are expensive - I have about 20 un-used ones) - it only cost about £5 from eBay - I will try and dig up the brand / seller for you.

The tip cleaner that I use is the stuff that Radio Shack (we still have one in my town) sells. It does a pretty good job. I'd like to see what you use.
 
I shall take a picture of my set up and tools =)
 
Zetr0 has a great point about cleaning your work. I also use an electric toothbrush with IPA and a quick rinse to clean my PCBs. I also have a handy little handheld air compressor to blow out any excess water before letting the parts dry thoroughly. This leaves me with a nice, clean device.

Some flux reside left by certain solder can be extremely difficult to remove so I ended up switching to a solder with a water soluble flux core. The downside is that it burns off faster than other fluxes so you may not get a good flow on a ground plane connection or a solder joint that requires extra heating. However, I use a flux pen to add a bit extra when needed to overcome this small obstacle. That minor inconvenience is more than made up for when it comes time to cleaning the flux.

Good luck!

Heather
 
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Hello,
Louis Rossman gave some usefull links recently, i'll repost them here:

✖ TOOLS SUGGESTED:
● Soldering Iron: http://amzn.to/2cKkMyO
● Preferred tip: http://amzn.to/2d5MgPn
● Micro Soldering Pencil: http://amzn.to/2d5MWUP
● Micro soldering tip: http://amzn.to/2oZPz40
● Hot Air station: http://amzn.to/2d5M7Lw
● Hot Air EXPENSIVE: http://amzn.to/2cYI6tY
● Microscope: http://amzn.to/2iLrE16
● Microscope LED light: http://amzn.to/2nzfPT2
● Flux: http://bit.ly/2cYIx7t
● Solder paste: http://bit.ly/2epK1JE
● Tweezers: http://amzn.to/2d5NBpi
● Multimeter: http://amzn.to/2otI9FA (I suggest this, cheaper) http://amzn.to/2cYJY5T (what I use, needlessly more expensive)
● Multimeter Probes: http://amzn.to/2cKkvMh
● Fume Extractor: http://amzn.to/2d5MGoD
● Solder: http://amzn.to/2cKkxUp
● Crest CP500D Ultrasonic cleaner: http://bit.ly/2pnKL5h
● Branson EC cleaning fluid: http://amzn.to/2cKlBrp
● Jumper wire THIN: http://amzn.to/2eqF5T7
● Jumper wire THICK: http://amzn.to/2eAJ5AU
● Nitri... (mehr)
regards,

Viktor
 
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