[Dragonfly DIY] $30 eBay 937D soldering iron teardown and review

I wanted to replace the aging (and lousy) Radio Shack soldering irons that we've been using for teaching people to solder for years now, and these seemed to be good IF they weren't also lousy. I picked up a couple of them to test. Short answer, they're surprisingly good given the price, probably a great choice for a beginner.