Soldering takes place at a lower temperature than brazing ... The acetylene gas from a compressed gas cylinder flows through a venturi in the torch drawing air into the gas where they are mixed before ...

Folk artist Ren Gengshun shows an engraving he made with electric soldering iron in Zhengzhou, Central China's Henan province, Dec 9,2014. Ren has been practicing pyrography for 30 years with ...