Temperature controllers are generally separate units that the iron plugs into. They are small, easy to use and relatively inexpensive.
It operates similar to a light dimmer switch. By dialing the control to a higher or lower setting, more or less electricity is fed to the iron. This increases or decreases the iron temperature, allowing the tip temperature to be controlled.
Ceramic Heating Element Irons
A temperature control/iron combination offers you greater control and flexibility than a temperature controlled tip iron when working with different metals and solder mixes. Look for one that is at least 80 watts. Since the flow of electricity to the tip is consistent and never completely stops, encounters with cold spots are nearly eliminated.
Hakko Soldering Iron FX 601 (stainedglassexpress.com)
These irons are relatively new to the stained glass trade. They are made with highly efficient ceramic heating elements. Like a ceramic room heater, they produce a consistent temperature using less electrical wattage during operation. When initially heating and when reheating during “recovery” periods, they can draw a “burst” of power exceeding100 watts and then efficiently reduce electrical consumption, often below 60 watts, during the soldering process. The result is efficiency and economy.
A remarkable feature of ceramic heater irons is they generally reach operating temperature in less than 60 seconds. Of the three types of irons, the ceramic heater type best maintains consistent tip temperature.
Irons with Temperature Controlled Tips
These irons are supplied with an internal regulator in the tip that does not allow the iron to exceed a predetermined temperature. An example would be a 600°F tip. The iron heats to that temperature then “shuts off.” When heat is required, the iron “turns on” again. Tips are available in predetermined temperatures up to 800°F. These irons are easy for beginners to use because the temperature is automatically maintained for you, however, as your skills increase, you may prefer to control the amount of heat yourself for different soldering situations. The limited amount of control may become frustrating as your soldering skills increase. With this type of iron you will likely encounter “cold spots” where the iron will not melt your solder. These cold spots occur when heat is being drawn out of the tip faster than it is being replenished. You will need an iron with a minimum of 100 watts.
The Weller 100 is one of these irons.
Stainless Steel Heater Technology
These are nice stable irons. Best to use them with a separate controller. The biggest advantage is if you drop this iron it does not have a ceramic element that is very easily going to break. These are little workhorses.
Weller SPG80 Soldering Iron (stainedglassexpress.com)
100 Watt Pro Soldering Iron (stainedglassexpress.com)