The Hakko FX-601 soldering iron is lightweight and reliable, and has a temperature controller built right in! It's no wonder that it has become the most popular iron for the stained glass hobbyist. We use them in our classes here at Whittemore-Durgin, and the students quickly fall in love (with the iron, not each other).
More than you need to know about the temperature control feature: The FX-601 is sold worldwide, and the international standard for measurement is the metric system. The United States is the only industrialized country in the world that does not use the metric system as its official system of measurement. Since there is not enough room to print both °F and °C on the handle, the international Celsius standard was used. If you don't have a clue how to convert °C to °F, a very simple method (and somewhat close approximation—for stained glass work anyway) is to just double the Celsuis value. So, using the doubling method, about 500 °C is equal to about 1000 °F. This method will bring you within the general ballpark. If you are still having problems wrapping your mind around these temperature readings, think rheostat. Rheostats have no temp readings or settings on them, and people have been using them just fine for years. Comes with a 3/16" tip.