I didn't know you have a 12v soldering iron. Is it good? 

I didn't know you have a 12v soldering iron. Is it good?

Just the same as a normal one, just a different supply voltage

I do soldering when I need to. I have both a butane and regular 240v soldering iron and use whatever is convenient.

Solder guns and Sensitive circuit boards-knew someone that tried using a soldering gun on a board that has COMOS devices-they were blown from the induction effects from the solder gun-there is a VERY strong AC electromagnetic field around the solder gun tip.Have seen warnings NOT to use soldering guns on boards-only pencil type irons with grounded tips-and the tip energized from a LV power supply.

The real problem is most likely unearthed iron and capacitive (or resistive, if isolation is compromised) leakage from 230V line power to the tip

The advantage of LV soldering irons is not as much the LV itself, but the fact that they can be left unearthed without resulting in the same leakage. This means, that the iron does not hard short to Earth everything you touch with it - So it might prevent damage when you handle the board and somehow you are at some potential, or when the board is still energized (something as trivial as a CMOS backup supply battery or charged capacitor in there)

Guys my tip of my Hakko iron is starting to get some of the residue, and i'am cleaning it with the gold tip cleaner. Should I get a new tip?