Our Guide to Linseed Oil
As a maker of linseed oil products, I'm very aware that there is a significant amount of confusion about the linseed oil you can find on store shelves. What is the difference between Raw and Boiled Linseed Oil and how are our products different?
On a hardware store shelf you'll find two products, Raw Linseed Oil and Boiled Linseed Oil. In almost all cases, the Boiled Linseed Oil will have driers added (see Driers explanation below). Meanwhile, the "raw" linseed oil is actually linseed oil which has been boiled (it's just considered "raw" in the sense that it does not have driers added). If you've been using Raw or Boiled Linseed Oil, and you want to tell if your Boiled Oil has driers added, just pour it into a clear container. Driers are a dark brown coloured liquid and make the oil appear an easily distinguishable brown colour which is not typical of pure linseed oil (whether it has been washed or boiled or treated in any other way). Typically, pure linseed oil will be a light yellow to reddish orange colour.
Our products are different and labelled differently (and more accurately) in order to avoid confusion as much as possible. For example,
Our Raw Linseed Oil is the same as Hardware store Raw Linseed Oil. It has been filtered, dewaxed by chilling, and refined. It is then cooked for a few hours.
Our 40 Hour Double Boiled Linseed Oil is quite similar to Raw Linseed Oil but it has been heated at 120C for a total of over 40 Hours. If you are used to using other "Raw Linseed Oil" this product will perform similarly. Also, if you are using linseed oil for any interior application **other than floors**, such as on furniture and tool handles, we recommend giving this oil a try.
It is very pleasant to work with compared to "Boiled Linseed Oil" and dries well with a bit of buffing. However, this product is specifically NOT recommended for floors, as with the pressure exerted by walking on floors the oil can leave a slight slippery feel on your shoes which will last up to a month until the oil fully cures. However, having said that, I personally do use this oil on my floors because that slight slipperiness does not bother me at all, so it's a personal preference.
Our Refined Boiled Linseed Oil (with Japan Drier added) is the 40 Hour Double Boiled Oil with Japan Drier added. This product will be the same as other "Boiled Linseed Oils" that you will find on a hardware store shelf.
Japan Drier contains primarily Manganese, with lesser amounts of Cobalt and Zirconium. Manganese is a common metal found in nature, and acts as an oxidative catalyst which is able to transfer oxygen to the oil at an exponentially faster rate compared to the oil naturally absorbing oxygen from the air on its own. Cobalt is a similar metal with the same function. Zirconium has a different drying function, as it is known as a "through drier" which helps with the drying of the oil molecules that are below the surface. This makes the drier incredibly useful in some situations, most noticeably on floors and when applying in cool weather. However, if you wish to simply apply a nice buffed oil finish on furniture or tool handles, the drier is really not necessary in most cases.
The most important thing to note about linseed oil is that it will always dry, even if you apply it in much less than ideal conditions. The oxidative curing of linseed oil is a chemical reaction which cannot be stopped. It can be greatly slowed down by lower temperatures, but once it warms up it'll continue at the same rate as before.
- Dawson Detwiller
page created January 2024