Favorite PCB cleaners

Nope, same issue. The refractive index of light gases is nearly wavelength-independent until you get into the UV.

Cheers

Phil Hobbs

Probably not. The assembly house I prefer to order from specifically states soldering under N2 atmosphere. Their lead free soldering looks excellent though.

Fred Bartoli wrote in news:4f64d1ba$0$1736$ snipped-for-privacy@news.free.fr:

isopropyl alcohol is NOT DRINKABLE. it's toxic internally.

back in PMEL,we used to have 95% ethanol for cleaning Johannsen gauge blocks;that was drinkable,it's about the same as Everclear.(I'd advise mixing in fruit punch...) for that matter,you could buy Everclear to use on your PCBs,but it's not going to be cheap.

Robert Baer wrote in news:0bGdnaBeIJP0o_jSnZ2dnUVZ snipped-for-privacy@posted.localnet:

the fluid that makes the vapor probably is very low viscosity and would easily flow under the parts. perhaps even drawn under them by capillary action.

I used it and all I had to do, is ask for it. It's just the 99.9 stuff was kind of dangerous to drink

I distinctly remember, some NASA high sped tape machines required ethanol to make them work.

Greg

Do you even have enough brains to know that there are at least three major types of alcohol molecule?

Thanks for confirming that.

Having done a bunch of rework, I am often surprised at the piles of crud under some components after a 10 minute run in an ultrasonic cleaner with pure alcohol.

I used to use some stuff made for PCB cleaning, it was a mix of isopropyl alcohol, ethanol and ethyl acetate. I'm guessing that maybe you can make ethyl acetate by mixing ethanol and acetic acid. But, I'm not a chemist. Anyway, that stuff seemed to dissolve and keep in suspension crud that would stubbornly stick to the board otherwise. But, it is pretty expensive.

Jon

I got bitten by that one myself, quite recently. At my PPOE, I could get electronic-grade solvents from stock. I'll have to bite the bullet and get a flammable storage cabinet so I can keep the good stuff in the lab.

Cheers

Phil Hobbs

Oh. I keep a gallon can of acetone in my office, and little squirt bottles of acetone, alcohol, flux, and water on my workbench. Is that bad?

That depends on the insurance policy, and since I don't own my building, on the lease. Generally they insist on flammable cabinets for storage of larger quantities of solvents and so on. It's also a good idea on general principles--you can put out 500 ml of burning solvent a lot more easily than a gallon.

At my PPOE, when I needed to violate some safety rule, I'd do it in my office rather than in the lab--they never, never audited offices. (I wasn't building nuclear reactors or anything--it was stuff like etching Cu-Ni off pyroelectric films with ferric chloride, when I didn't have a proper fume hood in the lab.)

Cheers

Phil Hobbs

If you're going to decant it into appropriate safety-vented small containers for use, don't forget the RTK labels (and a filing system for the manufacurer's MSDS if you dont have that set up already). Sooner or later someone will want to see it.

Best regards, Spehro Pefhany

I'll probably standardize on Everclear. You can drink that stuff. ;)

Cheers

Phil Hobbs

I bet that you still need the MSDS and labels unless you leave it in the consumer packaging.

You going to run it in from Connecticut or something? ;-)

Best regards, Spehro Pefhany

Absolutely. It can't be sold in NY, but AFAIK it's okay to bring it in yourself.

Cheers

Phil Hobbs

Dummies. What one buys at the drug store is NOT "ethanol" either!

It is ISOPROPYL. BIG difference.

AT ALL. You can only buy grain alcohol at the liquor store! The "lab" stuff is too expensive.

OK, here's a little test:

It's a little Bellin SO8 adapter board. It's clean now (using our infamous board degreaser) and pins the meter on the 1e14 ohm range.

Next, I'll try some greasy fingerprints. Then maybe resolder and leave lots of flux, and let that soak for a couple of weeks.

This Keithley takes a long time to settle on the top range, an hour at least, so this is definitely a spare-time project.

Now guess when the next drop will fall.

It is clear to me you eat s*it all the time. Do us a favor and die.

It's a bit irritating that a bottle of highly flammable Everclear can be shipped via Fedex Ground from NJ to Western NY for a small fraction of the cost of shipping a carefully sealed bottle of (also flammable) solder flux (the latter attracts Hazmat charges). Last time I think it was $60 or $65 extra for a 1-gallon bottle.

Best regards, Spehro Pefhany