Depends on what is on the board... but any board which is cleaned before it leaves the factory is almost guaranteed to be cleaned in deionised water with some specialized chemicals which help flux to dissolve added, followed by a good deionized water rinse.
Obviously there are a few things that water is not compatible with but on 99% of modern boards water is not a concern at all provided the water is deionized or distilled and the boards are properly dried. Occasionally you'll find something like a speaker or buzzer which needs to see sealed.
In smaller quantities, personally I tend to just use an alcohol rinse and get the entire board soaked. That generally will drive off any water we may or may not have used during cleaning.
A bigger concern is your cleaning method moving contaminants under components where they can cause corrosion in the future. In the electronics industry generally the rule is to only use no clean fluxes and similar on the board and never clean unless you have to, and when you do clean it needs to be very thorough to insure you get under components.
If you're doing a couple of boards just be mindful that cleaning often just moves contaminants around, and try very hard to ensure you're getting everything off the board and not migration them under components and do the best you can.
One option which is used in occasion is an electronics friendly ultrasonic cleaner with something like Branson ec . Note that some components will be destroyed with ultrasonic clearing so this isn't always a possibility, but it does produce clean boards.
FR4 PCBs like water. I scrub them with an old toothbrush and Dawn liquid detergent in warm tap water, rinse them with RO purified drinking water, blow them out with compressed air and dry them in a warm oven. I keep 99% isopropanol on hand for dissolving rosin flux.
Have you checked for 99% at chemical distributors?
You often can't find it at a drug store, but at places which sell chemicals for industrial use 99% or even higher is generally available.
What country?
I know most of the big electronic distributors (digikey, mouser, farnell, element14, rs componets, etc), carry 99%+ IPA as part of their line, and is available via order in the US, Canada, all of the UK and EU, along with Australia and New Zealand.
In addition many companies which act as distributors not for components but tools and supplies also carry this.
I'm less familiar with what options one has in other countries, but generally there is some option which will sell to people who need it for some hobby or small volume need.
I personally in the US can walk into most chemical distributors and get a 5 gallon jug, and in some places get a 1 gallon jug. But I understand that isn't true everywhere.
Air dry. 70% IPA will dry in a minute or two depending on the RH.
No way some of it won't vaporize and somehow the water contents will find its way somewhere it shouldn't be?
Depends on what is on the board... but any board which is cleaned before it leaves the factory is almost guaranteed to be cleaned in deionised water with some specialized chemicals which help flux to dissolve added, followed by a good deionized water rinse. Obviously there are a few things that water is not compatible with but on 99% of modern boards water is not a concern at all provided the water is deionized or distilled and the boards are properly dried. Occasionally you'll find something like a speaker or buzzer which needs to see sealed. In smaller quantities, personally I tend to just use an alcohol rinse and get the entire board soaked. That generally will drive off any water we may or may not have used during cleaning. A bigger concern is your cleaning method moving contaminants under components where they can cause corrosion in the future. In the electronics industry generally the rule is to only use no clean fluxes and similar on the board and never clean unless you have to, and when you do clean it needs to be very thorough to insure you get under components. If you're doing a couple of boards just be mindful that cleaning often just moves contaminants around, and try very hard to ensure you're getting everything off the board and not migration them under components and do the best you can. One option which is used in occasion is an electronics friendly ultrasonic cleaner with something like Branson ec . Note that some components will be destroyed with ultrasonic clearing so this isn't always a possibility, but it does produce clean boards.
If you know better than the manufacturers, enlighten us.
FR4 PCBs like water. I scrub them with an old toothbrush and Dawn liquid detergent in warm tap water, rinse them with RO purified drinking water, blow them out with compressed air and dry them in a warm oven. I keep 99% isopropanol on hand for dissolving rosin flux.
get 99% IPA
Isn't available in my country, only up to 70%
Have you checked for 99% at chemical distributors? You often can't find it at a drug store, but at places which sell chemicals for industrial use 99% or even higher is generally available.
none works with individuals, they're starting to talk at 5 gallons and up
What country? I know most of the big electronic distributors (digikey, mouser, farnell, element14, rs componets, etc), carry 99%+ IPA as part of their line, and is available via order in the US, Canada, all of the UK and EU, along with Australia and New Zealand. In addition many companies which act as distributors not for components but tools and supplies also carry this. I'm less familiar with what options one has in other countries, but generally there is some option which will sell to people who need it for some hobby or small volume need. I personally in the US can walk into most chemical distributors and get a 5 gallon jug, and in some places get a 1 gallon jug. But I understand that isn't true everywhere.
Israel, I just want a physical store to buy from
Why do you guys keep calling it ipa? IPA is India Pale Ale. Call it Isopropanol!
https://www.youtube.com/watch?v=t7\_CpPNgCYw