Stop-out varnish asphaltum

Black asphaltum ground to cover parts of the metal to protect them from being etched in the acid bath.
€ 15,56
€ 40,62 per 1 l
incl. 19% VAT , plus shipping costs
  • Available immediately

Asphaltum Varnish

Black Bitumen Cover Varnish to protect covered parts from being etched.
Stop-out Varnish prevents covered parts to be etched in the acid or in ferric chloride solution and other mordants.

Suitable for:
  • printmaking - cover and protect the back of copper, brass and zinc plates and for making aquatinta
  • electronics - prepare pcbs for etching and retouch defects in the photopolymer resist with stop-out varnish
  • modelmaking - etching of metal plates
  • Jewellery - structurize gems, bracelets and rings with ornaments
  • blacksmith - paint marks on knive and sword blades prior to etching or electro-etching.


bitumen, rosin and turpentine.


Use a soft brush to cover the areas You want to protect. Methylated spirits or paint thinner may be added to make the stop ground more fluent.
Can also be used as a hard ground for subsequent work with the etching needle.


Before the plate is submerged in the mordant, let it dry for at least one hour. Heat and air ventilation speeds up the drying process.


To strip the varnish after etching, use a solvent like acetone or turpentine.
Alternatively the MungoLux Cleaner can be used. It is solvent-free and based on modified vegetable oils.

Use in well ventilated room only.
Other names: Strawhat Varnish

Shipping weight: 0,35 kg
Content: 0,25 l