Ferric Chloride

  • Ferric Chloride- safest and best etch for our purpose
  • Better etch than Nitric Acid
  • Ferric Chloride etches straight down, not sideways
  • In liquid state it is non-toxic, there are no gases, 
  • Water molecules do not break down, water evaporates
  • Add table salt when first mix - this initially charges it
  • Used Ferric Chloride works best
  • When mixing from powder-- use respirator, gloves, face shield
  • Aerator moves solution and makes the etch bite faster
  • Periodically filter the solution and dispose of residue. 
  • Residue is mostly copper but still needs to be disposed of via hazardous waste removal
  • Baume 48-50    begins to solidify at Baume 53.
  • Ferric is extremely water soluble, there is no risk to the pipes because of its immediate dilution. 
  • No danger to pipes unless you were to pour concentrated solutions into the pipes without water and allowed them to gather in the pipes.
  • Ferric Chloride is used by water treatment plants to clean water and is one of the biggest industrial users.