On Sat, 07 Jan 2006 19:52:45 +0100, soffee83 <soffee83@...> wrote:
> Stefan, what are you cleaning a really dirty coated tip with? Is a
> soft extra fine steel wool OK? I've got a few of them too, but I've
> been pretty happy with the sharply ground coppers, now that I'm
> tinning them better.
I have never gotten a tip dirty enough to need any of that.
There can be several reasons why a tip doesn't wet well:
If you run at high temperatures the tin will oxydize.
If you run it "dry" the iron plating will oxydize.
There were also problems with some no-clean fluxes that were simply way
too weak to keep the iron wetted.
Finally the plating can be worn through, then nothing will help.
To recover a tip that doesn't wet properly try this (in this order, and
stop when it's ok again!):
Wipe on moist sponge / apply flux core tin. Sometimes this must be
repeated a few times to work. Larger wires have usually more flux and you
can also try liquid or solid soldering flux.
Use stronger activated flux (ideally special tip cleaner flux, or plumbing
flux). Make sure to clean that off when done.
If the above doesn't work you are officially allowed (by weller for
example) to use fine emery paper or a very fine steel brush. I reckon
steel wool is OK too. Use MINIMUM amount of abrasion that gets it working
again. Do this while hot and apply tin immediately.
To avoid any trouble:
Run the iron as cool as works well - a little cooler can like double tip
life.
ALWAYS keep tin on the tip. When you wipe it, immediately wet again. Don't
ever leave dry.
Don't use your iron as screwdriver or to lever things out or any other
stupid things.
Only use a proper soldering iron sponge and deionised (distilled) water.
Use a slightly moist sponge, not dry, not soaking.
Never shake the solder off by knocking the iron against something (heater).
Use electronics tin ideally with mild rosin flux.
As long as you treat it well a quality longlife tip will last for many,
many years.
>
> Not sure if I asked here, but I was wondering if anyone's ever seen a
> wide, flat tip for heating multiple IC legs at once? I was thinking
> how nice it would be to have something shaped like a hammerhead shark.
There are all sorts of shapes you can possibly imagine, any many you
can't. The more exotic the more expensive of course.
For a special tip you rarely need you can always make it out of copper.
There are tips that heat all pins of DIL ICs, same for SMD. There are also
tips with a gap for 1206 and other SMD sizes, which i would quite like to
own...
>
> Someone suggested heating an upside-down board from behind with a
> torch once, and I tried it. They said the components would simply drop
> out of the board onto the floor. Well, now I've got a nice old foot-
> long server card here with plenty of thru-hole digital IC's and pretty
> black polka dots on the back if anyone needs it. I think I hit it with
> MAPP gas, but it may as well have been ice water.
You are supposed to light the torch ;-)
No seriously, this is not quite the best thing to do, while it does work.
Better get a hot air gun with temperature regulation. It will still
sometimes damage the PCB because air is such a bad heat conductor, and it
takes rather long to transfer enough heat to melt the solder. I almost
stopped all-out desoldering of PCBs completely, i keep them in boxes and
go through them when i need components.
The proper tool for desoldering is a desoldering iron or gun. It beats all
other methods (braid, solder sucker, hot air) by a huge margin.
The cheapest ones are these:
<http://www.interboard.co.kr/bbshop3/img/item/70_s.jpg>
But it is better to have a gun or a tip for a normal iron like these,
where you can switch on the vacuum from a pump:
<http://www.mbr.ch/Loet-Entloetsysteme/Hakko/474Handle.jpg>
<http://www.pkelektronik.com/productPics_big/0051319099.jpg>
Those will desolder PTH baords without pulling out barrels and non-PTH
boards without lifting pads, and will also not burn the boards like hot
air can do.
ST