Do you clean your boards?

Should I clean the boards after assembly? Why? Why not? What do you do?

And while we’re at it, what’s wrong with lead-free solder exactly?

Nothing is wrong with lead free solder, in fact its easier to work with than unleaded but our European Fellows decided that its wise to ban the medium poison Lead from Solder and to compensate they spread Mercury in Energy saving Bulbs all over the World. The Lead in the solder its only dangerous if you grind and eat the solder, the Mercury from the Bulbs is extremely dangerous because you will inhale it as soon as a Bulb breaks and is magnitudes more poisonous.

Oh, and i never clean PCBs. I use leaded solder that leaves next to no traces. No, the Flux residues don’t harm you solder joints, at least for timeframe i can tell from my own experience (25 years).

Ok, but is the leaded solder better in any other way, or is it just easier to handle?

Lead free solder needs higher temps to melt. You get better joints with leaded.

I clean my board only because of OCD. I like them to look squeeky clean

It needs a higher temperature iron, and it grows tin whiskers over time which can cause shorts.

Organic flux and water to clean. Leaves the board spotless.

I started using Kester 24-6337-6401 with water-soluble flux after spending a couple of days chasing down a problem caused by a tiny whisker that was hiding in a flux residue. It was absolutely not visible until I finally decided to clean the board, even under magnifying glass and strong lights. With water-soluble flux i clean the board a few times: once after low profile parts are in, then after sockets go in, then after electro caps, etc. The board is clean and shiny, helps to spot less than perfect joins too. All it takes is a minute or two under running warm water with a brush, and a few minutes with a hair drier.

/me high fives kvitekp

if you are interested in approaching a professional standard of PCB assembly you should remove all flux residue - many reasons why this is a best practice have already been noted

kvitekp has the goods on what to use - I have a bunch of rosin core solder I have to go through and all the convenient cleaners for that kind of stuff are kinda nasty

the sooner you clean after soldering the easier it is to remove all the flux

i never clean up my dirty deeds. maybe i should?

If you soldering on a nice white “4Pole Mission PCB”, ethanol can be a good solution i think

To me it feels totally unnatural to wash electronics with water… but maybe i just have to get used to the idea…

@shiftr as long as you dont turn it on, you’re fine. Once you try it, I doubt you’ll ever go back

So Kvitekp, so the idea is you wash away the flux with water after you’ve completed your soldering? (assuming you use water soluble flux solder)

Yeah, using warm water in your kitchen sink. Then dry with a regular hair dryer. This is a lot nicer than those chemicals you have to use to clean up normal resin based flux.

That sounds easier. Off the topic, how fine is the tip you guys use for these boards? I haven’t begun yet, but some of the holes look very small.

I use a rather massive tip, since you just poke the component leg trough the hole, heat it while applying solder & presto = done :slight_smile:
(There is no need to stick the soldering iron into the hole, if that was what you were planning :D)

Nah more about not touching the non metal bit… but I think mine will be ok, having had a look at it.