Posted by Gary Dodge on January 22, 2003 at 10:57:44:
In Reply to: brown spots posted by Angel on January 22, 2003 at 09:44:10:
Well Angel,
I seriously doubt that I'm getting brown spots from a sponge, I don't use a sponge! Don't use paper towels either.
I use Sal-Ammoniac Water. It is a simple solution of sal-ammoniac salt and water. With proper technique that must be learned, of jabbing just the tinned tip of the iron into the water sharply (a slow dip won't work at all), you create a thermal shock of sorts that breaks off everything but the tin from an iron tip leaving it absolutely clean. Cleaner that any type of wipe can possibly clean it since it cleans all surfaces of the iron simultaneously. With a sponge or towel the first side you wipe is already oxidizing as you wipe the second and third surface, etc.
If your jab is done correctly there is very little cooling of the iron as the steam envelope that is created around the tip as the junk explodes off insulates it from over cooling.
( I should note that if you are prone to working with a small or relatively cool iron, this technique will not work for you.)
You can say that the brown spots come from anything you like, I just know that if I try Glastar flux I get them, and the folks who come into my shop asking why they get brown spots always turn out to be the ones using Glastar flux.
To me that is reason enough to use a flux that doesn't allow them to form.
If you are not getting them it is possible that you work with a cooler iron or some other variable, but that is irrelevant, nobody should have to change their work habbits to accommodate their flux. Just get the stuff that works!
GaryD
: Gary, I know this is a common perception....that certain fluxes leave brown spots behind. They also say it about the Classic 100 Gel and the Soldermate 11. I don't get spots...at all...with ANY flux. I routinely use the Classic and the Glastar and Canfield blue Soldermate etc. I wipe often on a wet towel and never have spots. I really believe that sponges are at the root of a lot of gunk problems on tips and spots on seams. If you use a towel and SEE how much junk you're wiping away, common sense will tell you that a little piece of sponge can't handle it, no matter how much you rinse it while you work. You and I use a Hakko 456 and they hold that heat rsulting in a LOT of residue.
: The only way to clean a sponge is to wash it with detergent because plain water won't get the dirt out. Well, if you use detergent, you've contaminated that sponge and every time you wipe on it after that it's going to add MORE black residue to your tips. Sponges were introduced because they're small and fit into that little holder at the base of a lot of Iron rests. They were convenient and compact. That doesn't make them any good for really keeping a tip clean.
: OK, thre's my SPONGE RANT. :)
: : Glastar flux tends to leave dark brown spots on your solder lines, but those usually wash off in your cleanup.