Chemtronics Flux Off: How to use? - Page 1
Forum section: electronics / projects

author: NivagSwerdna
author_rank: Super Contributor
timestamp: March 23, 2021, 09:50:17 am
content: OK... so this is a really dumb question...So I bought some Chemtronics Flux Off... and I even watched a video...but I am still slightly unclear as the best way to use it!Specifically... it's a solvent just like Isopropyl Alcohol so if I add it then the flux just dissolves and then reappears as a thin film of flux evenly distributed across the board!Am I meant to rinse after?

author: wraper
author_rank: Unknown
timestamp: March 23, 2021, 10:28:35 am
content: You need to blow dissolved flux away with compressed air or use paper wipes like kimwipes to absorb it. Preferably several times so no residues are left.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 23, 2021, 10:32:18 am
content: Sometime i call them residues displacement, it will clean to a certain point, i work in a pcb assembly shopWe use atron ac207 or vigon sc200The problems i have with chemtronic cleaners and other brands, they move flux residues away and dissolve them ... but traces remains on the pcb, i even used brakes cleaners (done some tests on scrapped pcb's) and some of them did a better job at cleaning and removing flux lollEven tried a Melamin cleaner/solvent, and this one is almost perfect (dry pretty fast, and bust flux residues, solder residues pretty fast)The pcb's we build are rf signal amplifiers, and some of the residues are affecting the board in many ways ... adjustments, signal quality etc ...A good shot of atron and problems are gone,but you have to rince the board, not cleaning it in the equipment caseAnd one of our board as a battery cell, i simply remove it before cleaning it if needed.A mix of 5% atron in 1L of warm (not hot) water does a great job.Chemtronic was doing a better job than MG Chemical (boy this one stink awful) but they don't do a total cleanup in my case.AND some of them may attack some plastics BEWAREReally depend of your needsAs Wraper wrote : yep Q-tips and clean wipes may help, but sometime it's not enough

author: Gyro
author_rank: Super Contributor
timestamp: March 23, 2021, 11:13:33 am
content: Quote from: NivagSwerdna on March 23, 2021, 09:50:17 amYep, it's just a solvent. It will dissolve and hold the flux in 'suspension' until it evaporates again. You need to mop it up or remove it in some way before that happens. Gravity works too if it's practical to hold the board vertical on an absorbent pad.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: March 23, 2021, 11:23:14 am
content: "residues displacement" Exactly... a bit like the story "The Cat in the Hat Comes Back"I was thinking... just rinse in water after? (Not sure of the solubility of flux off with respect to water)

author: cheater
author_rank: Regular Contributor
timestamp: March 23, 2021, 04:00:00 pm
content: Dissolve, then rinse off with IPA or even water (doesn't have to be distilled either, after all it'll carry all that crap with it). Probably wiping off the largest part of it first is your best bet.

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2021, 04:41:10 pm
content: I have used a fair amount of the Chemtronics Flux-off Rosin over the years for repair of vintage electronics using Kester 44. The boards are small so I stand them on end on top of an folded absorbent wipe to let gravity do its thing. It always takes at least two cleanings, sometimes three to get all traces of flux off of the board.The rosin version is plastic safe and in fact makes a good plastic gunk cleaner, easily removing old cal stickers and their residue.