Is 91% pure alcohol good on circuit boards ?

[Bill]

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

 

[Robert Grizzard]

Bill <elect21st@aol.com> wrote:

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

Industry uses absolute IPA. If you can avoid temptation, Everclear
works extremely well.

HTH

 

[Tweetldee]

"Bill" <elect21st@aol.com> wrote in message
news:8fb59540.0311081545.6b372215@posting.google.com...

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

91% doesn't leave much of a residue.. so long as it's not contaminated with
lanolin and other additives that make it feel good on your skin. The closer
to 100% the better. I have used acetone as a cleaner for many years....
does a great job as long as there are no plastics that may be attacked by
it. Acetone is more aggressive than alcohol, and shouldn't be used without
good ventilation.
--
Tweetldee
Tweetldee at att dot net (Just subsitute the appropriate characters in the
address)

Never take a laxative and a sleeping pill at the same time!!

 

[go]

Also clean it up with Isopropyl (ISP) Alcohol after you have done the
soldering, you can spot solder shorts easer.


Bill wrote:

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

 

[Loose Cannon]

No, but it sure makes good hooch!

 

[oldfogie]

"Bill" <elect21st@aol.com> wrote in message
news:8fb59540.0311081545.6b372215@posting.google.com...

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

I've used 190 proof 95% grain alcohol bought at a liquor store.

 

[jakdedert]

A lot of gasoline atifreeze products are 99.?% alcohol. I bought a couple
of bottles so labeled for a dime apiece on closeout a few years ago, and
haven't used them up yet....

jak

"oldfogie" <nospamoldfogie@earthlink.net> wrote in message
news:6zCrb.19265$Oo4.16547@newsread1.news.atl.earthlink.net...

"Bill" <elect21st@aol.com> wrote in message
news:8fb59540.0311081545.6b372215@posting.google.com...
Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

I've used 190 proof 95% grain alcohol bought at a liquor store.

 

[Andre]

"Loose Cannon" <mcg01@995.ca> wrote in message news:<vqua1h1punrg8e@corp.supernews.com>...

No, but it sure makes good hooch!

Andre's technical tips 101 :-

Tip *37. Acetone makes short work of the white deposits on PCBs after
exposure to water.

Tip *38. IPA also cleans off fingerprints from PCB edge connectors.

Tip *39. Vinegar cleans up battery corrosion from alkalines and NiXX
cells (usually) then acetone will get the rest.



-A

 

[angelshamshel]

For cleaning passives, etc try 99% Isoprop
TIA

On Sun, 9 Nov 2003 15:16:47 -0800, "Loose Cannon" <mcg01@995.ca>
wrote:

No, but it sure makes good hooch!

 

[Ross Mac]

"Bill" <elect21st@aol.com> wrote in message
news:8fb59540.0311081545.6b372215@posting.google.com...

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks
Lab grade alcohol will not leave a residue.....And I bet Everclear won't

either...though it might leave you with a residue!......take care, Ross

 

[Daniel L. Belton]

On 12-Nov-2003, "Ross Mac" <macroeng@example.invalid> wrote:

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks
Lab grade alcohol will not leave a residue.....And I bet Everclear won't
either...though it might leave you with a residue!......take care, Ross

I have used denatured alcohol many times with good results. and no
temptation to take a swig like with everclear... <g>

 

[Peter]

Bill wrote:

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

Alcohol is OK if the flux contains rosin (which most fluxes do). It just
solves the rosin residue, but you will have to remove it. A swab could
work. I prefer a cottonwool stick, that will absorb better and more. The
white residue might be activators. Always remove activator residues
because they contain ionic contamination, which under circumstances
could damage the board. Pure rosin residues are insulators and do not
any harm to the module, other than that it just doesn't look clean.

--
Peter Grison

 

[Ross Mac]

"Peter" <PietGrijs@hotmeel.com> wrote in message
news:bp3ddf$bcq$1@news4.tilbu1.nb.home.nl...

Bill wrote:

Often times I use 91% pure alcohol to clean a joint just before
soldering. Some techs say alcohol is not good and leaves white
residue. What do you guys recommend to clean a joint before and after
soldering ? Thanks

Alcohol is OK if the flux contains rosin (which most fluxes do). It just
solves the rosin residue, but you will have to remove it. A swab could
work. I prefer a cottonwool stick, that will absorb better and more. The
white residue might be activators. Always remove activator residues
because they contain ionic contamination, which under circumstances
could damage the board. Pure rosin residues are insulators and do not
any harm to the module, other than that it just doesn't look clean.

--
Peter Grison

That's interesting Peter!...I always wondered what the difference between

91% or so Isopropyl and the Lab grade stuff. We would use the lab grade
stuff to clean air bearings and if we didn't we would get that white film
you spoke of......
Take care, Ross