Homebrew PCBs

Bob,

I'm no iron expert, but that does sound like a pretty low wattage. I 
think my general duty "weak" one is a 23W. Could it be anything in the 
melting point of the solder you're using?

FWIW, I had the same problem with most of my reground copper tips 
recently, and had been talking to people here and in another forum. It 
turns out, I was waiting too long between preparing a nice, clean tip 
and coating it. I started cleaning it well with steel wool and even 
some ferric chloride on a paper towel, and then smearing a glob of 
flux on it and immediately reinstalling it and heating it. I'd start 
applying solder before it was hot enough to melt, and then as soon as 
it did, I could wipe it all around the tip and clean it off with a 
sponge periodically, leaving a nice shiny coating. I think the metal 
was oxidizing or something while it sat before.

-Good Luck!

George