I've read people recommend isopropyl alcohol (99%) to clean their PCBs.
I do not think those are available locally. I've only seen the "rubbing" alcohol stuff. Are they substitutes are the available from the "corner" shop (i.e. easily available without resorting to percy and other similar shops)?
Thank you.
I do not think those are available locally. I've only seen the "rubbing" alcohol stuff. Are they substitutes are the available from the "corner" shop (i.e. easily available without resorting to percy and other similar shops)?
Thank you.
My absolute favorite is semiconductor grade 99.999... % pure isopropanol, but that is more expensive. If you can find 90% rubbing alcohol, it should work. The price is right... try it and see if it's good enough for you.
dnsey said:
the usual ones I can see are 640mL/L solution. but I'll ask if they have a stronger solution. thank you.
You can get 99% Isopropyl from the chain drug stores. It's stocked right along with the 70% rubbing alcohol. If your drug store doesn't have it, check a medical supply center. You can get good swabs there too. 99% Isopropyl works great. Don't soak things too long. Things like rubber sealed electrolytics etc., might not fair too well.
It depends on your boards of course... but good ole soap and water works wonders. Pots, switches, and tranformers can make this impossible. But the vast majority of boards built these days are cleaned with water. Follow this with a good soak in RO water and 1/2 hour in the oven at it's lowest setting... ~150-160 F.
Just what type of board?
Ethyl Alcohol is also very good... your local hardware shop should have it cheap... "De-natured Alcohol". It's just ethanol with some poisons added so the wookiees won't drink it.
🙂
Just what type of board?
Ethyl Alcohol is also very good... your local hardware shop should have it cheap... "De-natured Alcohol". It's just ethanol with some poisons added so the wookiees won't drink it.
🙂
i haven't used alcohol on pcbs before so the question might sound ignorant.
I can use alcohol to clean the pcb before and after soldering components. is this right?
thanks again
I can use alcohol to clean the pcb before and after soldering components. is this right?
thanks again
The best rinse will depend on what flux you use. I insist on using rosin core flux, as I find the fumes from water soluble and "no clean" fluxes to be a lot more irritating. For rosin core flux, 90% isopropanol works quite well, and is pretty cheap ($1-2 per quart in the U.S). One usually finds it right next to the 70% isopropanol "rubbing alcohol" in stores that stock it.
I don't rinse until after everything is soldered in order to limit the solvent exposure for the components. Isopropanol is on the approved list of solvents for electrolytic capacitors.Evenif it gets through the end seals, it doesn't damage the works inside. Don't use chlorinated solvents under any circumstances. They clean off flux residudes very well, but they also seep into the end seals of electrolytics and cause the insides to disintegrate over time. Acetone is also not a good idea, as it eats a lot of plastics, especiallly polystyrene.
When you do rinse, give the board a good flush-down to carry away all the flux. Use something like an old toothbrush to loosen up stubborn deposits. The best approach is to use a pie pan or a poly container full of alcohol for the main scrub-down, then a final flush with clean, uncontaminated alcohol, so there are no residudes left behind. If you are stingy with the solvent, you just end up with a sticky circuit board.
I don't rinse until after everything is soldered in order to limit the solvent exposure for the components. Isopropanol is on the approved list of solvents for electrolytic capacitors.Evenif it gets through the end seals, it doesn't damage the works inside. Don't use chlorinated solvents under any circumstances. They clean off flux residudes very well, but they also seep into the end seals of electrolytics and cause the insides to disintegrate over time. Acetone is also not a good idea, as it eats a lot of plastics, especiallly polystyrene.
When you do rinse, give the board a good flush-down to carry away all the flux. Use something like an old toothbrush to loosen up stubborn deposits. The best approach is to use a pie pan or a poly container full of alcohol for the main scrub-down, then a final flush with clean, uncontaminated alcohol, so there are no residudes left behind. If you are stingy with the solvent, you just end up with a sticky circuit board.
Come on, 70% is good enough
" ... I can use alcohol to clean the pcb before and after soldering components. is this right? ..."
Come on e you guys, using industry grade 90% is probably over kill for home and short run projects ... and if you do it twice, clean, rince w/70%, clean and rince again ... AND use a little elbow grease = Work!! = scrub it = then the results will be better than just a single soak in 99.999 fine Iso Alki.
'Cause the water in the 70% does some cleaning work too.
Why do you think computer motherbaord designers and short run manufacturers clean their boards off ... in the shower !! ?? !!! (This is absolutely true, I kid you not.)
" ... I can use alcohol to clean the pcb before and after soldering components. is this right? ..."
Come on e you guys, using industry grade 90% is probably over kill for home and short run projects ... and if you do it twice, clean, rince w/70%, clean and rince again ... AND use a little elbow grease = Work!! = scrub it = then the results will be better than just a single soak in 99.999 fine Iso Alki.
'Cause the water in the 70% does some cleaning work too.
Why do you think computer motherbaord designers and short run manufacturers clean their boards off ... in the shower !! ?? !!! (This is absolutely true, I kid you not.)
The big assemblers mostly use water soluble flux systems, so the dish washer approach works just fine for them. They are concerned with dealing with large quantities of solvents due to environmental considerations. Some manufacturers also use no clean fluxes, but the boards often look like they've been stored in a chicken coop, and they can have long term problems with creepage. I for one would not use a no clean flux with anything associated with high voltage.
If you use rosin core solder, the 70% isopropanol will work, but it takes a lot more diddling to get a squeaky clean board, as it doesn't deal with the non-polar content of the rosin as well. The 90% stuff is a lot easier to work with if you can get it - I've used both....
If you use rosin core solder, the 70% isopropanol will work, but it takes a lot more diddling to get a squeaky clean board, as it doesn't deal with the non-polar content of the rosin as well. The 90% stuff is a lot easier to work with if you can get it - I've used both....
There are alot (REALLY) of pro circuit board shops that use dishwashers for SMT board cleaning... the only difference being is that they use RO water and no dishwasher soap.
Wrenchoone,
I agree, the waterbased fluxes are more obnoxious. If you listen to the Californians, they insist that rosin or water based vapors should be whisked away by a fan or such. The beauty thing I have found about water based stuff is that you can load a spray bottle with flux and pre-flux your boards a few minutes before soldering. On through-hole stuff, you get beautiful fillets on the back side with less solder. On SMT stuff with fine pitch, nothing beats water based flux for "snap" when you are drag soldering.
It took me awhile to learn, I am blind, I have to drink a pint to stop shaking from the coffee that I need to combat the hangover, but I can solder 1/2 mm pitch now with relative ease.
Pinkmouse,
Thanks... let's get more recruits. Water based stuff doesn't make anybody upset... you can pour it right down the drain.
I still use rosin core stuff, but only for gizmos that don't like water.
And, I don't wash it off... leaves that "hand made" patina.
🙂
Wrenchoone,
I agree, the waterbased fluxes are more obnoxious. If you listen to the Californians, they insist that rosin or water based vapors should be whisked away by a fan or such. The beauty thing I have found about water based stuff is that you can load a spray bottle with flux and pre-flux your boards a few minutes before soldering. On through-hole stuff, you get beautiful fillets on the back side with less solder. On SMT stuff with fine pitch, nothing beats water based flux for "snap" when you are drag soldering.
It took me awhile to learn, I am blind, I have to drink a pint to stop shaking from the coffee that I need to combat the hangover, but I can solder 1/2 mm pitch now with relative ease.
Pinkmouse,
Thanks... let's get more recruits. Water based stuff doesn't make anybody upset... you can pour it right down the drain.
I still use rosin core stuff, but only for gizmos that don't like water.
And, I don't wash it off... leaves that "hand made" patina.
🙂
I have a bottle of the Kester rosin core flux that I use for pretreating connections that may be difficult. It smells nice (a bit like old Vicks Formula 44), and you can practically write your name with the soldering iron on a pre-treated surface. I'm usually working with boards that have been cut with an LPKF routing machine. If it's a surface mount board, I coat it with flux and pre-tin using my iron. It makes soldering those little flecks of electronic dirt much easier.
The 70% alcohol often leaves a film. It's harmless but doesn't look nice. 90% is better in this regard. Sometimes I will also use soap and water afterward and give it ascrub with the toothbrush.
As said earlier ther are some components you can do this with -- just leave those to last.
As said earlier ther are some components you can do this with -- just leave those to last.
Can you still buy that stuff... if so, what is the part number?
And yeah, I like the smell of good ole' "44"... makes me think I'm camping.
oh, and WTF is LPKF???????
😕
And yeah, I like the smell of good ole' "44"... makes me think I'm camping.
oh, and WTF is LPKF???????
😕
The Rosin flux I use is Kester #1544, if I remember correctly. If you look around, you can find someone that sells it in the quart size.
LPKF is a German firm that makes a couputer controlled routing machine for cutting PCBs from blank copper clad. You feed in the Gerber files, it comes up with an optimized job file that it uses to drill the holes, isolate the traces, and remove big areas of unused copper, in that order. We use two of them at work for fast turn prototypes (all our protos are fast turn...).
LPKF is a German firm that makes a couputer controlled routing machine for cutting PCBs from blank copper clad. You feed in the Gerber files, it comes up with an optimized job file that it uses to drill the holes, isolate the traces, and remove big areas of unused copper, in that order. We use two of them at work for fast turn prototypes (all our protos are fast turn...).
- Status
- Not open for further replies.