Although there are some who swear that temperature-controlled irons are the
way to go, they didn't work for us. Maybe it's just having a classroom-setting,
and far too many students using them, but they didn't last. They burnt right out on us. For our purposes, learning to control the iron at one temperature was a
far greater skill to have mastered than to try to teach 125 students at a time to futz with controls. It just didn't work for us.
I used Weller irons for years. Mika irons, too. We've used $35-60 ones, we've
had temperature controlled ones. Then I found Hakko. We use Hakko 456’s because they are workhorses. They have been discontinued. Nooooo!!!!! Buy one specifically for stained glass, with a 3/16” tip. You can try getting a 20-30 dollar one made by Weller. Go with 80 to 100 watt, but some will say that this
doesn't matter much. Lower wattage is fine, too It needs to go to 800-1000
degrees for good solder flow. Upgrade when necessary to a 50-60 dollar one.
UPDATE as of 8/14: Due to unique circumstances, I was able to buy
replacement irons for my classes this year. Since the 456s are gone, we got
the Hakko FX601-02 Adjustable Temperature Irons. So far, so good. Using a special tool that comes with the iron, we can lock them at the 410 degrees
Celsius (about 800 degrees or so.) This solves a major problem we used to
have when we first tried the temp controlled irons- students changing the
temperatures. They go up two more temperature settings- up to 1000 degrees, which is waaaay too hot for us. They aresmaller, and the cord is a bit long.
2017 Update: The irons have been nice! As the tips wear out, the temp can be raised. The replacement tips are about $15 each. Not bad. A typical hobbyist
probably can have this iron for a good long time.
NOTE: the heating element inside the metal shaft is made of delicate
ceramic. DO NOT tap or hit the iron against anything to shake off excess solder. The element may break. (Learned this the hard way...)
Here are my picks:
Mika 100W Soldering Iron $32.00 A good one to start.
Weller Iron $40
Weller Iron and mini-stand $60
Hakko FX601-02 Adjustable Temp Iron $60-70
And a nice holder:
Studio Pro Soldering Iron Holder