Removing Liquid flux RMA from trousers

Thread Starter


Joined Jun 4, 2014
I put down my bottle of liquid flux (RMA) and it leapt of the bench, bounced off my leg before ending up on the floor.
Will a normal wash get the flux out of my trousers?


Joined Jan 23, 2018
The flux bottle should include instructions for cleaning it off the circuit board. Usually that is either water or alcohol. Do not put it in the regular wash because the flux may get on other things, and the hot wash may bond it to the cloth forever.


Joined Mar 30, 2015
So normal cool wash, on there own would work?
I recommend spot cleaning before washing with other clothes. If it's a lot of flux, you also don't want it getting stuck on the washing machine.

Cold water should work; it's the emulsifying action of the soap that gets it off. I often get pitch from fir and pine trees on my hands. I usually have it washed off with soap and water before the tap water gets hot.


Joined Jan 18, 2008
Do you have any ZEP floor stripper? If not, look for any other floor stripper with butyl cellosolve in it. They are relatively mild, but great in the presence of water and detergents. Test first on an inconspicuous place. They do have a distinctive odor that will wash out. As mentioned in another thread, I am experimenting with shorter chain length cellosolves, like ethyl cellosolve. They are more volatile and have a more pleasant odor, but you would have to buy the chemical.

Denatured ethanol probably will also work.


Joined Mar 30, 2015
The problem is that it would be a rather big spot - about half a leg.
I'd still clean off as much as you can before putting it in the washer. Better to be safe than sorry.

If that's too much bother, cut off the legs and use them for shorts.

I have most of a 1 liter plastic bottle of flux I bought in the 80's. I transfer half an ounce or so to a plastic bottle with a dispenser tip so the big bottle is rarely in a position to be spilled. That way I don't need to worry about large spills (which is unlikely because it's pretty viscous) and I don't have much to rejuvenate if I forget to put the cap back on - which has happened a couple times over the years.


Joined Mar 19, 2019
Worked in a chemical refinery that produced rosin. It is not water-soluble and while alcohol (gasoline or any solvent) will dissolve it, mineral oil will soften it to the point where a detergent can dissolve the oil/rosin mix. This was critical when treating rosin splash burns at the critical care burn center to remove the solidified rosin while not further damaging underlying tissues. High vapor pressure solvent will evaporate leaving rosin behind where low vapor pressure solvents, such as mineral oil, will stay in solution and be dispersed by detergent.