I ran into a vague recipe for finishing wood with 3 coats of boiled linseed oil and then wax. I have used linseed oil as an agent in oil paint but never used 'boiled' linseed oil before. It seems to dry almost instantly and gives a beautiful, deep rich color to the wood. I have been putting on 3 or 4 coats, waiting 10 minutes between coats then letting it dry overnight before waxing. Am I doing this the right way? Exactly what is boiled linseed oil? What is the drying time needed before applying wax? Is it a good thing to use?
-
It's time to cast your vote in the April 2025 Turning Challenge. (click here for details) -
Congratulations to Steve Bonny for "A Book Holds What Time Lets Go" being selected as Turning of the Week for 28 April, 2025 (click here for details) -
Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.
finishing with boiled linsed oil
- Thread starter jamie
- Start date
jamie said:
Jamie,
"BLO" is a penetrating oil that will polymerize and is a part of a number of quality oil finishes. Its formed film is rather soft which is why varnish or urethane resins are added in for increased durability. You are however, mistaken in thinking that the finish is "dry" by the next day. Polymerizing oils such as BLO and other oil-based finishes (flax, soy, tung, poly, nut oils, etc.) must go through a "curing" cycle that can last from a week or two to several months. The curing process is a chemical reaction in which the oil molecules take in oxygen and form linked polymers that form the film finish. During this cure time the finish film, which can be several mils thick at first, also compacts and pulls down thinner on the wood surface. This is why some oil finishes can be built to lacquer-like gloss but later show wood pores and scratches in the wood that were missed. Thus, when you apply your wax "the next day" you're actually interfering with your oil's curing because you're cutting it off from the most easily available source of oxygen needed to complete the cure. The result will be weak bonds in the film.
I suggest that you take a bit of mineral spirits on a soft cloth and gently remove the applied wax, then set your piece aside for a week or two to let it cure. If you want a high shine, you can then buff your piece with rubbing compound.
Final note on wax. It gives a nice shine when first applied and buffed, but almost all waxes are hydroscopic, they attract moisture in the air, which then causes them to become cloudy and dull requiring further buffings and waxings. Since wax does not penetrate wood (molecules are too large) it is a surface treatment at best and gives little actual protection. OTOH, if you allow your oil-film to properly cure and then buff it without wax, the shine you get will last.
Good Luck
Last edited:
- Joined
- Jan 27, 2005
- Messages
- 13,098
- Likes
- 5,557
- Location
- Dalworthington Gardens, TX
- Website
- pbase.com
Mark gave you an excellent explanation about using boiled linseed oil (also known as BLO amongst woodworkers and woodturners). I thought that I would throw in a few words about linseed oil. When you buy linseed oil, you will find that it comes in two types: raw and boiled. The names are somewhat misleading, however. Raw linseed oil is just plain oil without any additives. It is very slow drying and is mixed with oil-based paint when it is necessary to extend the drying time and improve leveling when the finish is being brushed. Boiled linseed oil is NOT a "cooked" version of raw linseed oil. It is linseed oil to which metallic drying agents have been added to accelerate the curing process that Mark described. What you mistook for drying was actually the oil soaking into the wood. It is OK to add another coat of oil over the first one, but thoroughly wipe off any oil that has not soaked into the wood after about 15 minutes or so. Don't apply any more BLO until the first layer has had a couple weeks to polymerize for the same reason that Mark stated about not applying wax too soon. If you do decide to apply wax, I recommend using carnauba because it is the least hygroscopic natural wax that I know of.
Bill
Bill
Just a reminder that is probably unneeded....
Dispose of your oil soaked rags carefully. The same polymerization process Michael referred to creates heat that can cause a small pile of oil soaked rags to ignite. Be really careful with them.
This is true with any of the oils that cure....linseed, tung, danish oil, etc.
Dispose of your oil soaked rags carefully. The same polymerization process Michael referred to creates heat that can cause a small pile of oil soaked rags to ignite. Be really careful with them.
This is true with any of the oils that cure....linseed, tung, danish oil, etc.
never unneeded
Advise about spontaneous combustion is probably never "unneeded".
Didn't have spontaneous combustion but had the "pile of oily rags" issue forced home one time when I ignited a pile with sparks from the grinder.
Personally, a safety reminder is never out of place!!
Advise about spontaneous combustion is probably never "unneeded".
Didn't have spontaneous combustion but had the "pile of oily rags" issue forced home one time when I ignited a pile with sparks from the grinder.
Personally, a safety reminder is never out of place!!
Hi Jamie,
I started out with BLO, like alot of us do. Kinda not sure why this ends up being the first thing tried cause, in all actuality, it ends up giving an not great finish by my experience and is not the easiest thing to work with.
My recommendation would be to save the linseed oil for tool handles and baseball bats, and pick up a can of eurythane oil. There are even some fast drying ones out there that are designed as wipe on finishes. Give a piece a nice, soaking coat, wipe dry, let dry for the recommended time X2, then recoat. Keep doing this till you've built the finish you like. Then buff and wax (carnuba on a buffer). For a quick finish, one coat and paste wax when dry.
Brands that are often used are Waterlox, Minwax, and whatever your local Woodcraft or Rockler's has on sale (heh, heh).
Good luck,
Dietrich
I started out with BLO, like alot of us do. Kinda not sure why this ends up being the first thing tried cause, in all actuality, it ends up giving an not great finish by my experience and is not the easiest thing to work with.
My recommendation would be to save the linseed oil for tool handles and baseball bats, and pick up a can of eurythane oil. There are even some fast drying ones out there that are designed as wipe on finishes. Give a piece a nice, soaking coat, wipe dry, let dry for the recommended time X2, then recoat. Keep doing this till you've built the finish you like. Then buff and wax (carnuba on a buffer). For a quick finish, one coat and paste wax when dry.
Brands that are often used are Waterlox, Minwax, and whatever your local Woodcraft or Rockler's has on sale (heh, heh).
Good luck,
Dietrich
- Joined
- May 16, 2005
- Messages
- 3,540
- Likes
- 20
Soak, dry and cure get confused a lot of times when people talk of finishes.
Linseed, which is from flax which is used to make linen with that crossword and Scrabble word "ret," soaks in fairly rapidly unless it's got high viscosity from additives or cold surroundings, which is why a lot of people like to cut the first coat or two with solvent or even warm it in a double boiler. Thinned oil behavior is why people believe that "Danish" oil hardens in the wood not on it. OK, but not far in.
Oils don't dry, they cure, as others have indicated. The boiled part of the name doesn't refer to an ethanol process, but the process of heating and bubbling the oil as done in the past. Heat speeds most chemical reactions, even exothermic ones like oil cures, and it's the oxygen that provides the cross-links. Take a bit of time between applications to let the oxidation get hold, though if you avoid standing oil you can certainly get by with the old "once a day for a week" rule of thumb. By wiping and rubbing you're not adding much to the surface.
You've probably had experience with the durability and flexibility of linseed as a finish other than the exterior of your house. Linoleum is linseed and matting and sawdust. Since it is flexible and the coats are thin and rubbed, wax is almost superfluous. You get good lustre from the film itself, especially if you've burnished the surface. As mentioned, waxes attract water, oils, as we know, resist and repel. Fortunately, properly done wax is thinner than the oil film.
Linseed, which is from flax which is used to make linen with that crossword and Scrabble word "ret," soaks in fairly rapidly unless it's got high viscosity from additives or cold surroundings, which is why a lot of people like to cut the first coat or two with solvent or even warm it in a double boiler. Thinned oil behavior is why people believe that "Danish" oil hardens in the wood not on it. OK, but not far in.
Oils don't dry, they cure, as others have indicated. The boiled part of the name doesn't refer to an ethanol process, but the process of heating and bubbling the oil as done in the past. Heat speeds most chemical reactions, even exothermic ones like oil cures, and it's the oxygen that provides the cross-links. Take a bit of time between applications to let the oxidation get hold, though if you avoid standing oil you can certainly get by with the old "once a day for a week" rule of thumb. By wiping and rubbing you're not adding much to the surface.
You've probably had experience with the durability and flexibility of linseed as a finish other than the exterior of your house. Linoleum is linseed and matting and sawdust. Since it is flexible and the coats are thin and rubbed, wax is almost superfluous. You get good lustre from the film itself, especially if you've burnished the surface. As mentioned, waxes attract water, oils, as we know, resist and repel. Fortunately, properly done wax is thinner than the oil film.