Which one of these soldering wires needs to be cleaned ?

[l3gi0n]

I am looking at these Soldering wires:

https://www.amazon.ca/Kester-24-6337-8800-Activated-No-Clean-Diameter/dp/B00068IJOU/ref=sr_1_3?crid=1CCMIDRYHJM8X&dchild=1&keywords=Kester+63%2F37&qid=1635531533&sprefix=kester+63%2F37%2Caps%2C78&sr=8-3

&

https://www.amazon.ca/Kester-24-6337-0010-Rosin-Solder-SPOOL/dp/B00068IJWC/ref=sr_1_6?crid=1CCMIDRYHJM8X&dchild=1&keywords=Kester+63%2F37&qid=1635531533&sprefix=kester+63%2F37%2Caps%2C78&sr=8-6



Which one needs to be cleaned ? and which one requires more cleaning ?

[ataradov]

What do you mean by "cleaned"? If you mean flux residue, then both are rosin core and both will leave flux residue. There is no difference between the two in this respect.

But it is rosin, so you don't have to clean it, it is not active, or conductive.

[BrokenYugo]

The datasheets for your study.

https://www.kester.com/DesktopModules/Bring2mind/DMX/API/Entries/Download?EntryId=958&Command=Core_Download&language=en-US&PortalId=0&TabId=96

https://www.kester.com/DesktopModules/Bring2mind/DMX/API/Entries/Download?Command=Core_Download&EntryId=1072&language=en-US&PortalId=0&TabId=96

Kester 44 is old school RA flux, fairly aggressive as electronics solder fluxes go, will wet out on old, tarnished, dirty, parts and boards just about as well as new clean ones. It can be cleaned, quite easily will any purpose formulated "flux cleaner" product, but it is not required as the heat from soldering will activate and use up most of the corrosive stuff, and the remainder will mostly be harmlessly locked up in the residue.

Kester 245 is a "no clean" flux. "No clean" has a somewhat complicated meaning, you don't have to clean it in most situations, but if you try, you had better do it as instructed by the manufacturer or you're gonna have a bad time.

[l3gi0n]

How do I clean the Kester 44 ? Swab+99% IPA would do ? Should I clean the joints or the PCB too ?  Can you tell me in detail what and where should be cleaned ?

I recently purchased this:

https://www.amazon.ca/gp/product/B005T8PL1Q/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

Can I use this to clean the residues  ?

Here is a quote from the DATASHEET:

The 44 series possesses excellent fluxing ability. The flux residues are non-corrosive, non-conductive and do not require removal in most applications under normal conditions of use. IPA will not clean the residues off the surface of the circuit board after the soldering process. If removal is required, a saponifier or cleaning agent specifically designed to clean a no-clean flux is required to clean the residues.

[Jwillis]

For rosin flux, IPA works great . Just swab it on liberally and the flux residue will soak into the swab . You can go over again with a clean dampened swab if you like then let dry .  For larger areas you can use a squirt bottle and a small nonabrasive brush . Tooth brushes and stiff paint brushes work pretty good . 

[BrokenYugo]

I've never used Kester 44 specifically but many people run into the dreaded white residue problem cleaning rosin flux residue with IPA, myself included. Success is more or less guaranteed with a proper flux remover.

It should be noted that unless you're working with super sensitive/high impedance circuits or burn the flux with poor technique it usually isn't a problem to just leave it be. The only must clean electronics fluxes are the water soluble ones, which pretty much have to be ultrasonic cleaned in distilled water to keep it from destroying the board. Only other time you have to be careful is with added flux, which may not all heat enough to activate if you really slather it on.

[jpanhalt]

Here's the SDS for Kester 5768 "saponifier" flux remover: https://www.kester.com/DesktopModules/Bring2mind/DMX/API/Entries/Download?Command=Core_Download&EntryId=1452&language=en-US&PortalId=0&TabId=96

Most notable is 2(2-butoxyethoxy)ethanol and ethanolamine.  The former is a member of the class readily available cellosolves: https://en.wikipedia.org/wiki/Glycol_ethers

Another brand's saponifier is just ethanolamine in water.