General > General Technical Chat
Brake cleaner is cheap and cleans PCBs really well
BrokenYugo:
--- Quote from: tooki on July 27, 2021, 03:46:34 pm ---
--- Quote from: M4trix on July 22, 2021, 12:39:31 am ---mmmm.... I'm happy with my IPA. :phew:
--- End quote ---
--- Quote from: floobydust on July 22, 2021, 07:46:00 pm ---IPA works fine, just let it soak in a bowl and it works really well. People don't have patience and resort to harsh chemicals.
--- End quote ---
The problem with isopropyl is that many modern fluxes, especially the no-clean types, are not fully alcohol-soluble. No amount of IPA will fully dissolve them, leaving behind the infamous white deposits. Ironically, cheap 70-90% rubbing alcohol may work better for these fluxes than 99% IPA, since many of those residues are water-soluble.
But commercial flux removers do a much better job, frankly, and do it in much less time. I a) can't have a bowl of IPA sitting around at work (and you'd still need a separate rinse!), b) not all components can be immersed, and c) I don't have the time to wait for things to soak. Why use navigable amounts of IPA and lots of time to achieve only an OK result, when a commercial product lets me use tiny amounts, does the job quickly, and leaves the boards squeaky clean??
--- End quote ---
Can confirm, I've tried to clean boards every way imaginable with 91% IPA and get the white crap, I even tried a vapor chamber. The stuff seems fairly insoluble in water too, you have to scrub it off. Haven't gotten far enough to figure out if it's the old 90s Radio Shack 60/40, The MG 835 RA, or both.
G7PSK:
Its the UV UVc being the main culprit due to its high energy from arc welding that breaks down carbon tet. to phosgene. IPA fumes wont cause you any harm in the quantities that most are likely to encounter. The same goes for brake cleaner and carb cleaner, unless you are sloshing it around by the gallon just ensure adequete ventilation.
ElektroQuark:
FWIW, with MG Chemicals No Clean Flux Paste Cat. No. 8341 and IPA you get TONs of that white residue. :palm:
tooki:
--- Quote from: ElektroQuark on July 28, 2021, 05:59:26 pm ---FWIW, with MG Chemicals No Clean Flux Paste Cat. No. 8341 and IPA you get TONs of that white residue. :palm:
--- End quote ---
Can confirm, as that’s the flux paste I have at home. As I said, very common for no-clean fluxes. But to be clear, MG does not claim it to be cleanable in IPA: they recommend “solvent systems” like [several of their flux cleaner products], so the facepalm isn’t warranted.
rdl:
IPA is a pretty poor solvent for most things. If it actually does work for something, then ethanol is almost always better.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version