Madder lake preparation

This recipe is for those who want to prepare their own oil color from raw chopped madder root. You can as well skip this process and buy Alizarin Crimson oil color for painters.

Equipment
  1. Enameled pot of at least 3 L capacity, {the solution must not get in contact with iron, similarly various glass cookery is not recommended, they may crack and spill the potassium carbonate}
  2. A plastic bucket, preferably of white color to easily identify the sediment, cca 10 L capacity.
  3. A precise thermometer, connected to an electronic relay which will turn the hotplate on and off to maintain a steady temperature.
  4. A suction hose.
  5. A funnel with coffee filters.
  6. An empty bottle.

Ingredients
  1. 180 gr chopped Madder root.
  2. 60 gr Potassium carbonate.
  3. 60 gr Potassium alum {Aluminium potassium sulfate}.

Preparation
  1. Add 2400 ml of tap water into the pot
  2. Add 60 gr od potassium carbonate and let dissolve.
  3. Add 180 gr chopped Madder root, stir thoroughly.
  4. Bring to 40°C for 36 hours. The temperature must not exceed 45°C for longer periods of time, otherwise the temperature sensitive Alizarin will turn brown. You may try to set 40°C on the thermometer and make its tip touch the bottom of the pot. Also, set the hotplate to its lowest setting. Stir occasionally.
  5. Put a filtering cloth into a plastic bucket, put a sieve onto the bucket and pour the Madder root solution in it. Wring all the liquid out of the chopped root, remove the sieve.
  6. Carefully lift the filtering cloth, tie it with a length of wire and hang it on a wooden stick across the top of the bucket.
  7. Let it drain for a while and then squeeze out the rest of the lake.
  8. Put 1200 ml of water into your empty pot and warm it up a bit {40°C}.
  9. Add 60 gr of alum, stir until dissolved.
  10. Add the resulting warm solution into the bucket with the drained Madder pigment and stir. The solution should froth profusely.
  11. Stir occasionally for 3 days.
  12. Add fresh water to the solution so that you fill the bucket to its brim.
  13. Let it stay for 36 hours.
  14. Drain the semi-clear water with a suction hose, stay well of the line of the sedimented pigment. If you are uncertain about the line, remove just one half of the bucket. Refill with fresh water and let the pigment settle for 24 hours.
  15. Decant again and refill with water. Let it stay for 8 hours.
  16. Repeat until you start draining clear water.
  17. Put a funnel into an empty bottle. Put a coffee filter in the funnel. Pour the sedimented pigment from the bucket into the filter.
  18. Let it filter for a couple of hours, or until the water no longer drips from the funnel.
  19. Collect the sediment into a jar and start drying out, stirring occassionally.
  20. When the paste gets too thick add a bit of thickened linseed oil and mix it in thoroughly.
  21. Continue stirring and letting the mixture stand until it thickens, and adding more oil to keep it pasty. After maybe a week you should be left with just oil paint.

Consider warming up the paste if you want to speed up the process {40°C max}. To test that there is no water present in the paste, put a little bit on your finger and spread it on a smooth surface. If there is water, the paste will coagulate in a typical "watery" manner, if the water has been sufficiently removed, you will easily create a consistent "oily" layer on such a surface.

This smooth paint can then be directly added to your oil varnish.

Category: Varnish recipes
Comment by 2.137.178.183
2015-03-01 09:46:53
Can you tell me what is madder in latin or in spanish, please?
Comment by 88.102.61.63
2015-03-01 20:36:08
In latin it is Radix rubiae tinctorum.