ART OF STAINED GLASS
The standard iron for stained glass is the Weller 100W. Lower wattage will slow you down, and can be inadequate, for example, for soldering brass lamp accessories to the lamps.
Use 60/40 solid core solder. Lead-free solder is also available for items that will be in frequent contact with fingers, children, or wildlife. Lead-free solder is more than twice the price of lead solder, but has very similar working properties.
Tips and Special Techniques
The beginner project foiled, temporarily framed in a jig, and ready to solder:
Note that the back of the project is seen on top, and will be soldered first. This is because the side which is flat against the board when the first side is soldered always looks flatter and has slightly thinner solder lines. The back of the project is where inequalities in the thickness of the various pieces of glass will stand out as irregularities.
In general, the jig should be prepared before grinding, and put to good use during the grinding stage. For such a small, one-off project, a jig is not really necessary, but is shown here for illustrative purposes.
Soldering, copper foil technique