Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Burnt solder flux, safe to use acetone?

Status
Not open for further replies.
You might have better luck with a a mixture of acetone and absolute ethanol. I don't have a clue as to what the pyrolysis products are, but some might be a little polar and absolute ethanol is a great solvent for such things. Just a little water (5%) changes the solvent potency of ethanol greatly. Absolute will dissolve fat; 95% is much less effective.

In short, try acetone. If that doesn't work (I suspect it may not), change to 50% to 75% ethanol (absolute or denatured) in acetone. My usual elixir for removing excess flux is that mixture (i.e, 75% absolute ethanol, 25% acetone). Isopropyl alcohol may work as a substitute for the ethanol. I just happen to have a lot of ethanol on hand.

John
 
i wouldn't try this on PCB - if you don't intend to remove the copper as well
Been using the ethanol-acetone mixture for more than 20 years. Haven't removed any noticeable amount of copper.

What do you use to remove excess flux?

John
 
Haven't removed any noticeable amount of copper.
possible , whats your technique?
What do you use to remove excess flux?
my sharp fingernails , then pure ethanol if i am to do more soldering otherwise i don't care as i'm not selling anything

the "paint removers" do not cause the copper to fall off - but when you next time solder with high temperature and try to make a firm connection between Cu and bad quality component lead by "rubbing" the solder to surfaces with the welder tip and the Cu is small area it might come off easier than just with excess temperature - i usually cover everything with solder in prior sometimes it's not enough to sucessful finish
 
Last edited:
Technique?
I either immerse followed by toothbrush or just toothbrush alone for larger boards.

I said nothing about "paint removers" -- a term that covers a very broad range of chemicals.

John
 
the "paint removers" do not cause the copper to fall off - but when you next time solder with high temperature and try to make a firm connection between Cu and bad quality component lead by "rubbing" the solder to surfaces with the welder tip and the Cu is small area it might come off easier than just with excess temperature - i usually cover everything with solder in prior sometimes it's not enough to sucessful finish
That would be where you are going wrong. Save your welder for car repairs and paint remover for decorating. Neither should go near electronics.

Mike.
 
ci139 : What's your point? Acetone does not remove copper traces from any PCB I have ever used. That gets back to your post #3. What evidence or literature can you present or cite to support your assertion?

Since the OP asked in general whether acetone was safe, I stand by my response. I failed to mention, however, that if the PCB contains components that have "sensitive" plastic, like a plastic optical window, I will omit acetone from my brew and use just ethanol or isopropyl alcohol. That action is taken as an "abundance of caution." I do not know and have not tested the plastics used for such windows or LED's. Although, I have had no problems with ordinary LED's used to show an active state. Shrouded connectors and so forth have not been a problem. I would be concerned about using neat acetone on some of them, but as stated, I do not use neat acetone for removing excess flux nor recommend it.

Additionally, with clear plastics, the effects of any organic solvent may not be immediate. Over a long time, the plastic may be more susceptible to crazing. One good example is acrylics (e.g., Plexiglas). It can be bonded with chlorinated hydrocarbons (e.g., chloroform), but that bond will show crazing years later. That is just one example, but relatively mild solvents like toluene or xylene or even oil-filled caulking can have the same effect.

John
 
and i said what i have experienced

what i suppose to do now - try to remove a past evt. from world history - because it does not fit your like

may be there are differences between acetone and acetone - or PCB and PCB - i don't know
 
Acetone removing copper??? Not a chance. Maybe you're thinking of Coppertone on asses?
I've always had good luck with alcohol. What I've found to work even better, on suitable components, is household ammonia and a toothbrush followed by a rinse with water, then a good blow drying. Commercial processes often use aqueous washes.
 
Personally, I use MethylEthalKetone "MEK" which works splendidly for removing flux although, in retrospect, I should NOT have mentioned it here. Acetone is probably not a good idea either. This should be filed under, "don't do as I do"..

If a particular plastic bears a close enough similarity to acetone, the acetone will dissolve or at least affect its surface, softening, smearing or even dissolving the plastic. Other plastics, dissimilar to acetone, will remain unaffected by the solvent.

Here is a link to a handy chart regarding various chemicals and their effects on various types of plastics: https://www.plasticsintl.com/plastics_chemical_resistence_chart.html
 
Last edited:
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top