View Full Version : Water souble flux

08-26-2006, 06:32 AM
Does anyone know where I can get water soluble paste flux.· I've searched everywhere I can think of but can't find it.


Sid Weaver
Do you have a Stamp Tester yet?


PJ Allen
08-26-2006, 07:58 AM
water-soluble flux


one gallon: 488CH2235· pen dispenser: 488CH450·

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Loopy Byteloose
08-26-2006, 05:24 PM
A gallon! that is a lot of SMDs.

I would be interested in the water-soluble flux being included in the solder core, but that seems unavailble.
Currenty, I am cleaning rosin flux from boards with 3M General Purpose Adhesive Cleaner.
I am sure that it is not doing my liver any good and may even cause liver cancer.

I was using alcohol, but found out that alcohol is actually corrosive to metals.
It immediate begins to oxidize solder.

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PJ Allen
08-26-2006, 08:35 PM
· Y'know... I just don't get this hobbyists "pretty-fying" boards stuff.· [Actually, I don't get·the mental process here at all·-- it's d**b.]

· The flux/rosin is in the solder for a reason.· "Cleaning" it off is a cosmetic consideration, but counter-productive at that: it's·the equivalent of·leeching.· The rosin protects the solder on the shelf and [watch this, kidz]·with proper technique, on the board, too (if you're going to heat/cook the joint till the flux turns black, then forget it.)

· The only validation for removing it is to coat the assembly afterward.· Some RF/HF·circuits·can be·adversely affected by rosin (when it gets betwixt and between·IC and transistor pins.)

08-26-2006, 09:37 PM
For "No-Clean" flux I would agree.
However RA (rosin active) and RMA (rosin mildly active) I think corrosion can occur if the flux is left on.
I'm not sure about water soluble flux, I can't think bathing your circuit in water would do it any good either ?


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08-26-2006, 09:47 PM
I have a small container of water soluble paste flux I bought from Radio Shack before they stopped carrying it.· I use it for all thru-hole and SMD soldering.· When the board is finished, I was scrub both sides with in warm water, then with soap and water.· Afterwards I dry the board in a 125 degrees oven for thirty minutes.· I have never had a problem with residual flux "interference" or with corrosion.· When this little container is gone, I will have to go back to rosin paste, which requires scrubbing with anhydrous alcohol.· So I can get by - it's just that the water soluble is· less troublesome.


PJ Allen
08-26-2006, 09:59 PM
Newzed said...
When this little container is gone, I will have to go back to rosin paste, which requires scrubbing with anhydrous alcohol.
Why?· I gave you a link with a gallon and a pen of water-soluble flux.· Too much, too little?·
It's not paste?· Well, look around there, they probably have it.

Bruce Bates
08-26-2006, 10:02 PM
Sid -

Good grief man, don't use the anhydrous alcohol for CLEANING, try it on the rocks with a twist of lime http://forums.parallax.com/images/smilies/smile.gif <HIC>


Bruce Bates

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08-26-2006, 10:11 PM
PJ, a gallon is way, way to much.· I could handle a pint or smaller, but not a gallon.

Bruce, the alcohol is 91 percent isopropyl - you can't drink the stuff!!


Kevin Wood
08-26-2006, 10:54 PM
I worked as an assembler for awhile, and we used liquid water soluble flux. After the boards were assembled, we washed them off with water and dried them with a hose connected to an air compressor. Nothing was ever damaged.

PJ Allen
08-26-2006, 10:54 PM
A pen dispenser is·less than a gallon; it's less than a pint, too.

488CH450 -- Kester Flux Pen

Designed to dispense the right amount of liquid.· For rework and soldering touch-up.· Formula 2331ZX Water soluble flux.· Lead Free Approved.

$3.85 ea

Oh well.·

You can lead a horse to water...

08-26-2006, 11:13 PM
PJ, I have a flux pen.· It just doesn't seem to work as well as the paste.· I guess maybe the paste is more concentrated, but I'll try the flux pen again.· Perhaps I'm not getting enough of it at the solder point.


PJ Allen
08-27-2006, 03:22 AM
OK, OK,...

I was at Ace Hardware and they have water-soluble paste flux in, like,·margarine containers.· Maybe it's not suitable for electronics work.

Cleaning PCBs in water is OK, so long as they aren't energized --·you just need to bake them out, like you're doing, or leave them out for a few days (use distilled water.)

I'll keep looking around.

08-27-2006, 03:32 AM
Thanks, PJ.· The stuff at Ace is for plumbing soldering.· Probably acid - I would be afraid to even try it.· Finishing up a board on SuperMill - I'll try the flux pen again and really compare it with the paste flux.