I began my latest batch of leaded linseed oil on July 27, 2021–38 days ago. I protected the oil from debris with a cover. I gently rocked the tray periodically to prevent surface skin.
When I checked the oil today, it was thick and sluggish which means it’s ready to decant and store.
Forgetting to form a single spout with the malleable lead, I spilled some of the oil when I poured it into the glass jar. This mistake was mitigated when the remaining oil filled the jar almost to the brim.
Here is the completed oil. While it is darker than raw linseed oil, it’s much lighter than black oil which is made by heating oil with sugar of lead.
To use it, I thin the oil with turpentine 1:2 or 1:3. It handles much better than raw oil and has more body and is altogether better than stand oil.
In my experience, the only oil that beats this oil is sun-thickened oil. Done properly, sun-thickened oil has the same thick, honeylike appearance as this leaded oil. While neither type of oil requires heat to prepare, sun-thickened oil takes longer and requires consistent exposure to the sun, which makes it harder to make in northern climates.
If you follow my original instructions, make sure you wipe the lead tray clean after decanting the oil. That way you can use the same tray for another batch.
This batch will last a long time.