Steady state micro welding

Steady state micro welding was an advanced engineering technique pioneered by the Lamadines. The Third Doctor used it to try to repear his Dematerialisation circuit. When smoke started to come from the circuit, Jo Grant thought it would start a fire and sprayed it with a fire extinguisher. However, the Doctor said that steady state micro welding "always produces more smoke then fire". (TV: Terror of the Autons)