Colophony cooked for 9 hours at 150 - 180 C- The temperature is gradually raised to keep the same viscosity
- Weight reduction 36%
- Lots of stirring!! especially in the first hour when it fumes a lot
Linseed oil heated to the same temperature and slowly stirred into the colophony - Cooked for 35 min together with the colophony
- Reducing temperature to ~100 C
Mastic drops added slowly while stirring - Cooked for another 15 min at lower temperature to 90 - 100 C until the varnish is very calm
Balsam turpentine heated to simmer - Slowly stirred into the varnish and cooked 5 - 10 min until calm again
Filtered and decanted into a glass jar | Colophony 120 g -> 77 g Linseed oil 75 g Mastic 13 g Balsam turp 40 g |
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