by BRNO_Bigot » 05 Feb 2018, 3:19 pm
The hot water method was most useful back in the days of corrosive primers.
Most of these primers were Potassium Chlorate or Perchlorate or closely similar compounds. When these went off, they would leave a salt behind of Potassium Chloride (similar to Sodium Chloride - table salt).
Cleaning this out with an oil mixture was really not too useful, but dissolving it in boiling water was the ducks nuts, easy and effective.
Coincidentally this also opened pores in the steel and allowed the other naughty bits to be scrubbed out.
With newer primer compounds, not as useful.
--
It's only when you look at an ant through a magnifying glass on a sunny
day that you realise how often they burst into flames.