Lay a double thickness of cheesecloth on a flat surface.
Place 1 lb. damar crystals on the cheesecloth. Pull up the edges, making a bag, and tie securely with string.
Fill a wide-mouth glass jar with 1 quart of pure gum turpentine. Set the cheesecloth with the damar crystals into the turpentine. Put the jar lid in place and secure tightly.
Wait 3 days for the crystals to completely dissolve, slowly moving the bag around in the turpentine each day to speed up the dissolving process.
Remove the cheesecloth bag, containing any remaining residue, from the jar and discard.
Pour damar concentrate mixture carefully through a double layer of cheese cloth into another wide-mouth jar, filtering out any remaining impurities. The solution should be the consistency of honey. If it is not thick enough, set the jar aside, without a lid, in a well-ventilated area until more turpentine evaporates.
Add 1 part of the damar concentrate to 1 part boiled linseed oil and 1 part pure gum turpentine. Combine ingredients thoroughly using a wood stir stick.