I*really* want to remove Kester 44 flux - what do I need to buy?

[cvanc]

I know you don't have to remove it but I just hate looking at it if nothing else. Plus it gets in the way of rework.

What will get this off nice and clean? I'm constrained for the need for 'hobbyist quantity' and don't want a gallon can of anything. Thanks...

[Kim Christensen]

I use a sharpened chop-stick to scrape/pick the bigger chunks off. Then I use 99% isopropyl alcohol with a brush and scrub/wash/flush the rest away. I'll also use a paper towel to soak up any now dirty alcohol while tilting the PCB so it runs toward the towel pressed against the PCB. This minimizes the cleaning area if the PCB already has large clean areas.

[GLouie]

I think I've found pure ethanol ("Everclear" sold at USA liquor stores) a bit better than the 91% isopropyl I can get from the drugstore at removing Kester 44. I'll hold the board vertically over a little tray of alcohol and dip a toothbrush in it and scrub the board a bit. However, I think the alcohol gets contaminated immediately, so when it dries it leaves still some flux residue. Then I'll dribble some fresh alcohol over the board with a fresh toothbrush a couple of times. Then some spot cleaning with an alcohol soaked rag and cotton buds. It's still never perfect, but it's cheap.

[jpanhalt]

Use ZEP Heavy Duty Acrylic Floor Sflripper diluted one part to 3 parts total with water and an ultrasonic for about 1 minute.

[nctnico]

I've found ethanol works better as flux remover compared to alcohol for cleaning up small bits of rework. But using real flux remover works even better but that stuff is in my shed for cleaning entire boards.

[johansen]

I've found ethanol works better as flux remover compared to alcohol for cleaning up small bits of rework. But using real flux remover works even better but that stuff is in my shed for cleaning entire boards.

without knowing what "real flux remover" you are talking about,

your post is a waste of space.

[jpanhalt]

I agree with the comments about ethanol; however, there seems to be some ambiguity.  Without a modifier, "alcohol" in casual conversations usually refers to ethanol.  Of course, an alcohol is simply a class of organic chemical.  I don't believe methanol works very well for flux.  E85 fuel may work.  I tried it once, but I haven't pursued that path.

Like others, I use ethanol for spot cleaning.  I sometimes mix it with about 25% acetone.  I prefer absolute ethanol versus 95% (Everclear), but absolute is harder to find.  At retail, I would not consider either inexpensive. 

ZEP floor stripper costs $10 to $14 per gallon at American box stores.  Considering the dilution, it is hard to beat for price in gallon quantities.  It can be saved between sessions if you use it frequently.  I don't, so I usually just discard after use.

[johansen]

acetone is a gamble, it can dissolve stuff you don't expect.

methanol has an undesirable smell, ethanol of course its denatured with stuff you shouldn't drink (but i have found out by experience that eucalyptus oil does not give me a hangover)

dishwasher detergent is very cheap, i have heard from many across 4 decades of folks that you can just toss your boards in the dishwasher.

alconox is also reasonably cheap and will probably work to remove flux very well in an ultrasonic cleaner. if the only thing you need to remove is the flux than 60$ of alconox should last you 100 pounds of solder.

[tooki]

I know you don't have to remove it but I just hate looking at it if nothing else. Plus it gets in the way of rework.

What will get this off nice and clean? I'm constrained for the need for 'hobbyist quantity' and don't want a gallon can of anything. Thanks...

A spray can of flux remover? Techspray, Electrolube, Microcare, and many others sell them. Look at the SDS and you should find a blend of one or more alcohols and some other solvent (often a very light petroleum like hexane). Some are heavy-duty versions containing acetone, but Kester 44 is fairly easy to remove, so I would avoid acetone since it can be aggressive to plastics.

There are also more expensive ones that use nonflammable solvents instead. IIRC 3M makes this.

My favorites so far are from Electrolube, thanks to the orange terpenes they contain, which give them a pleasant odor.

[GLouie]

acetone is a gamble, it can dissolve stuff you don't expect.

methanol has an undesirable smell, ethanol of course its denatured with stuff you shouldn't drink (but i have found out by experience that eucalyptus oil does not give me a hangover)

dishwasher detergent is very cheap, i have heard from many across 4 decades of folks that you can just toss your boards in the dishwasher.

alconox is also reasonably cheap and will probably work to remove flux very well in an ultrasonic cleaner. if the only thing you need to remove is the flux than 60$ of alconox should last you 100 pounds of solder.

At least in the USA, you can get ethanol meant for human consumption, which I assume is not denatured. I see Everclear is available in 151 and 190 proof (95%) at a liquor store. At work, we were able to order gallons of what was labelled as 200 proof ethyl alcohol USP, no mention of adulterants. I believe one use would be for food grade potions such as vanilla flavoring.