I’ve recently completed soldering the F6 amp pcb’s and used acetone to clean flux residue. While it did a good job removing the flux it did leave a very light somewhat sticky film behind. What’s best to clean this last bit of smudge?
Tried isopropyl and mild soapy water. Suggestions please
Tried isopropyl and mild soapy water. Suggestions please
Paint thinner, car auto variety.
Next time use iso straight, acetone removes the markings from parts and PCBs.
Next time use iso straight, acetone removes the markings from parts and PCBs.
Isopropyl alcohol is the safest to use. In a pinch, Everclear works, too. You can drink, at your own peril, what you don't use for de-fluxing.
Isopropyl alcohol or even methylated spirits at a pinch.
You have to rinse and blot, then rinse again to get all the haze off, it’s much worse if there was some sort of protective coating applied to the board, as per many vintage pieces of gear from the 70s/80s.
You have to rinse and blot, then rinse again to get all the haze off, it’s much worse if there was some sort of protective coating applied to the board, as per many vintage pieces of gear from the 70s/80s.
Just use a flux cleaner, this is the one I use and it is very effective.
https://uk.farnell.com/servisol/100019000/flux-remover-160-200ml/dp/3821470
a toothbrush is good for scrubbing into corners. After scrubbing spray with the flux cleaner again and blot it off with some kitchen roll.
Probably branded solvent.
Read the MSDS, you will find it is one of the above, and you are paying for the name.
Read the MSDS, you will find it is one of the above, and you are paying for the name.
> Just use a flux cleaner, this is the one I use {Servisol De-Flux}
YOU could read the MDS.
https://www.farnell.com/datasheets/3214655.pdf
Hazardous ingredient Registration number CAS-nr. EC-nr w/w % Hazard Class and Category Hazard statement Notes Hydrocarbons, C6-C7, n-alkanes,isoalkanes,cyclics,< 5% n-hexane 01-2119475514-35 - (921-024-6) 30-60 Flam. Liq. 2, Skin Irrit. 2, STOT SE 3, Asp. Tox. 1, Aquatic Chronic 2 H225,H315,H336,H304,H411 B,Q 1-methoxy-2-propanol; monopropylene glycol methyl ether 01-2119457435-35 107-98-2 203-539-1 10-30 Flam. Liq. 3, STOT SE 3 H226,H336 A propan-2-ol; isopropyl alcohol ;isopropanol 01-2119457558-25 67-63-0 200-661-7 10-30 Flam. Liq. 2, Eye Irrit. 2, STOT SE 3 H225,H319,H336 B Hydrocarbons,C3-4-rich, petroleum distillate Petroleumgas (1,3-butadiene < 0.1%) 01-2119485926-20 68512-91-4 270-990-9 10-30 Press. Gas, Flam. Gas 1 H280,H220 K,G n-hexane 01-2119480412-44 110-54-3 203-777-6 <3 Flam. Liq. 2, Repr. 2, Asp. Tox. 1, STOT RE 2, Skin Irrit. 2, STOT SE 3, Aquatic Chronic 2 H225,H361f,H304,H373,H315,H336,H411 A Orange, sweet, extract 01-2119493353-35 8028-48-6 232-433-8 0-1 Flam. Liq. 3, Skin Irrit. 2, Skin Sens. 1, Asp. Tox. 1, Aquatic Acute 1, Aquatic Chronic 1 H226,H315,H317,H304,H400,H410
It is a witch's-brew of specific refinery fractions. Yeah, it's got isopropyl , but some of that other stuff......
YOU could read the MDS.
https://www.farnell.com/datasheets/3214655.pdf
Hazardous ingredient Registration number CAS-nr. EC-nr w/w % Hazard Class and Category Hazard statement Notes Hydrocarbons, C6-C7, n-alkanes,isoalkanes,cyclics,< 5% n-hexane 01-2119475514-35 - (921-024-6) 30-60 Flam. Liq. 2, Skin Irrit. 2, STOT SE 3, Asp. Tox. 1, Aquatic Chronic 2 H225,H315,H336,H304,H411 B,Q 1-methoxy-2-propanol; monopropylene glycol methyl ether 01-2119457435-35 107-98-2 203-539-1 10-30 Flam. Liq. 3, STOT SE 3 H226,H336 A propan-2-ol; isopropyl alcohol ;isopropanol 01-2119457558-25 67-63-0 200-661-7 10-30 Flam. Liq. 2, Eye Irrit. 2, STOT SE 3 H225,H319,H336 B Hydrocarbons,C3-4-rich, petroleum distillate Petroleumgas (1,3-butadiene < 0.1%) 01-2119485926-20 68512-91-4 270-990-9 10-30 Press. Gas, Flam. Gas 1 H280,H220 K,G n-hexane 01-2119480412-44 110-54-3 203-777-6 <3 Flam. Liq. 2, Repr. 2, Asp. Tox. 1, STOT RE 2, Skin Irrit. 2, STOT SE 3, Aquatic Chronic 2 H225,H361f,H304,H373,H315,H336,H411 A Orange, sweet, extract 01-2119493353-35 8028-48-6 232-433-8 0-1 Flam. Liq. 3, Skin Irrit. 2, Skin Sens. 1, Asp. Tox. 1, Aquatic Acute 1, Aquatic Chronic 1 H226,H315,H317,H304,H400,H410
It is a witch's-brew of specific refinery fractions. Yeah, it's got isopropyl , but some of that other stuff......
Acetone is way too aggressive, attacks plastics, removes labels, etc. and to boot leaves behind a whitish residue; alcohols are mild and still more than enough competent to dissolve and remove rosin and flush other minor residues.
Above mix sounds more complicated than it is, because it includes all registration codes and damage descriptions, but can be reduced to, basically variants of:
* Hexane which is a solvent present in gasoline
* variants of propanol and propylene glycol ether which is is a "safe" solvent.
So much so that propylene glicol is present in eye drops and E-Cigs fluid, go figure.
* isopropyl alcohol : our old friend and which can do 90% of the removal job on its own, mechanical scrubbing (old toothbrush) will help it if other "helpers" are not used.
* butadiene which is probably used as an ozone layer safe propellant gas
so witches brew becomes Grandma´s Soup once you analyze the recipe 🙂
Glad to see that beyond the scary names, actually quite safe ingredients are used. GOOD.
Above mix sounds more complicated than it is, because it includes all registration codes and damage descriptions, but can be reduced to, basically variants of:
* Hexane which is a solvent present in gasoline
* variants of propanol and propylene glycol ether which is is a "safe" solvent.
So much so that propylene glicol is present in eye drops and E-Cigs fluid, go figure.
* isopropyl alcohol : our old friend and which can do 90% of the removal job on its own, mechanical scrubbing (old toothbrush) will help it if other "helpers" are not used.
* butadiene which is probably used as an ozone layer safe propellant gas
so witches brew becomes Grandma´s Soup once you analyze the recipe 🙂
Glad to see that beyond the scary names, actually quite safe ingredients are used. GOOD.
WD40 is transformer oil, with a little lubricant, and a lot of propellant.
Sells for much more than transformer oil.
USA it uses refrigeration propellant, the German version is LPG (cooking gas) as propellant...
MSDS says hydro treated Naptha, which is another (technical) name for transformer oil.
Like fancy shampoo saying it contains "Aqua"...water in plain English!
Sells for much more than transformer oil.
USA it uses refrigeration propellant, the German version is LPG (cooking gas) as propellant...
MSDS says hydro treated Naptha, which is another (technical) name for transformer oil.
Like fancy shampoo saying it contains "Aqua"...water in plain English!
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Is the Farnell version orange scented?
Basically it is iso alcohol spray, with gas propellant for the spray. The rest are stabilizers.
6.72 GBP for 200 ml spray which may be less than 100 ml after propellant removed.
33.60 GBP per liter with gas, or 67.20 as a liquid.
Iso Alcohol is 1.20 GBP per liter here...
Inexpensive, you said?
Iso Alcohol is used in the offset printing business, they buy in large quantities for use in damping.
So get some from a mate if you can, or buy from a chemical supply shop.
Basically it is iso alcohol spray, with gas propellant for the spray. The rest are stabilizers.
6.72 GBP for 200 ml spray which may be less than 100 ml after propellant removed.
33.60 GBP per liter with gas, or 67.20 as a liquid.
Iso Alcohol is 1.20 GBP per liter here...
Inexpensive, you said?
Iso Alcohol is used in the offset printing business, they buy in large quantities for use in damping.
So get some from a mate if you can, or buy from a chemical supply shop.
91% isopropanol is the way to go (available at drug stores/chemists just about everywhere). You need to be generous with the juice to flush off the board, otherwise, you will leave sticky flux residue behind. A toothbrush helps with cleaning off the stubborn bits. Giving the board a bath with clean alcohol after the first round of scrubbing and letting it drip dry is the best approach for a really clean board.
Isopropanol is a safe solvent for electrolytic capacitors and other sensitive components. Acetone is way too aggressive, and is death for polystyrene capacitors. Avoid chlorinated solvents at all costs, as they can kill electrolytic capacitors by wicking up inside and destroying the foils. We had one instance in my last job where our Far East factory was using trichlorethylene to clean boards, eventually causing some of the large HV snap-in caps on the board to fail and actually catch fire. The customer was none too pleased...
Isopropanol is a safe solvent for electrolytic capacitors and other sensitive components. Acetone is way too aggressive, and is death for polystyrene capacitors. Avoid chlorinated solvents at all costs, as they can kill electrolytic capacitors by wicking up inside and destroying the foils. We had one instance in my last job where our Far East factory was using trichlorethylene to clean boards, eventually causing some of the large HV snap-in caps on the board to fail and actually catch fire. The customer was none too pleased...
I use a fine screw driver or pointy tooth pick to break up large bits of flux, and a wire brush first, to clean off solder splatter.
Then like above, alcohol with a stiff brush, old tooth brush is very easy to use.
Then like above, alcohol with a stiff brush, old tooth brush is very easy to use.
The OP asked for suggestions - I made one concerning a product I consider cost-effective and that I've used successfully over a number of years. I feel no need to justify it further and the OP is free to take it or leave it.
Sprays I consider damaging to the ozone layer, and in most cases are not essential.
They just add to the product cost, and sticky nozzles irritate me.
Try plain iso alcohol if you want to.
He (OP) is in the USA, may or may not be available there.
And he has to clean up a boo boo because he used acetone first.
They just add to the product cost, and sticky nozzles irritate me.
Try plain iso alcohol if you want to.
He (OP) is in the USA, may or may not be available there.
And he has to clean up a boo boo because he used acetone first.
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I have tried plain iso alchohol but it didn't do as good a job as the product I use, hence my suggestion.
Thanks for the addition to our knowledge base, will keep in mind.
Tell us what type of solder you use, composition and flux cored or plain.
Soldering iron type, tip material.
Brand and type of flux used when needed.
Those things also count.
Tell us what type of solder you use, composition and flux cored or plain.
Soldering iron type, tip material.
Brand and type of flux used when needed.
Those things also count.
You have to be careful which alcohol you use. If you try rubbing alcohol (only 70% concentration, rest is water), things may not work so well. 91% is the way to go. If you can get absolute isopropanol, all the better. No-clean flux is harder to remove, and will take more scrubbing. You really should clean it off, though, as it can cause tracking for HV applications. I've seen boards so slathered with the stuff that it looks like a conformal coat...