Lately I've been fiddling around with Pop-Pop boats. My very clever but still un-wired friend Duke Croft has designed a model which incorporates some novel features, both in terms of vehicle design and in how it is manufactured. He recently had a change of circumstances (new job!) and now he no longer has time to pursue the project. But Duke has kindly given the whole kit and kaboodle to me and with his tooling and his tutoring, aided and abetted by Jerg Jergensen (who made some excellent stamping dies) and some tooling of my own devising, I am now preparing to manufacture a small lot of these craft.
One problem I found had to do with the silver soldering of the two boiler halves together. Duke had been carefully snipping little bits of solder and then painstakingly positioning them around the pre-fluxed rim of the two pieces. Heat was then applied from two sources: a Bunsen burner beneath to warm the whole assembly and an air-acetylene torch to chase the flowing solder around the rim. Trouble happens when the solder isn't evenly spaced and pin hole leaks result. I took it upon myself to create the device pictured below, which nips solder wire into little pieces about .031in. dia. and about .020in. long. These pieces are fine enough that they can be combined with flux to make a paste.
I'm a piker compared to this guy. For more on pop-pops check out the page put up by Vance Bass