Walnut oil

[Brian Deakin]

Do walnut oil products specifically marketed for woodturners offer any advantages over walnut oil sold for culinary purposes

[Brice Rogers]

I attended a seminar by Mike Mahoney who sells his own brand of walnut oil and was told that he (essentially) boils it which changes it to make it polymerize (harden) quicker. I think that if you are looking for a finish that will eventually cure, you want wood turning walnut oil. But if you are just oiling a butcher block, that it doesn't much matter.

I suspect that the heat-treated W.O. would not go rancid. But I am uncertain of culinary W.O. - - it seems like if it didn't cure that oxygen could have an affect on the protein in the oil as it does with other culinary oils.

[Ted Calver]

I tried finishing some of my early bowls with culinary walnut oil and found that they started to smell after 6 months or so. I had given one to a friend and she returned it, asking if I could put a different finish on it, so I re-turned it to get the outer layer off and finished it with Mahoney's utility finish, which dried nicely. Ended up having to do the same thing for our daily use bowls. Since then, Mahoney's and another similar product from Doctor's Woodshop have been my go to for food safe surfaces.

[John K Jordan]

I attended a seminar by Mike Mahoney who sells his own brand of walnut oil and was told that he (essentially) boils it which changes it to make it polymerize (harden) quicker. I think that if you are looking for a finish that will eventually cure, you want wood turning walnut oil. But if you are just oiling a butcher block, that it doesn't much matter.

I suspect that the heat-treated W.O. would not go rancid. But I am uncertain of culinary W.O. - - it seems like if it didn't cure that oxygen could have an affect on the protein in the oil as it does with other culinary oils.

I've read several reports over the years of problems finishing wood with walnut oil made for consumption.

JKJ

[Reed Gray]

Both culinary and bowl finish walnut oils are 'heat treated' to break down the proteins that can cause food allergies. They use different methods, and you get different results. Some food grade walnut oils cure, some don't. I use the Doctor's Woodshop oil. I don't know if it is really any better than Mike's, but the Doctor is from Oregon...

robo hippy

[Brian Deakin]

Thank all for your posts
I did find this reference https://en.wikipedia.org/wiki/Walnut_oil

Cold-pressed walnut oil is typically more expensive due to the loss of a higher percentage of the oil. Refined walnut oil is expeller-pressed (https://en.wikipedia.org/wiki/Expeller_pressed) and saturated with solvent to extract the highest percentage of oil available in the nut meat. The solvents are subsequently eliminated by heating the mixture to around 400 °F (200 °C).

[tom lucas]

I just use Boiled Linseen Oil for food finishes. You can also use it with shellac to get a more durable finish that is also food safe. Friction polish (BLO, DNA, Shellac) is my go-to for food grade. And it's also a great general finish too.

[Bill Boehme]

I've used La Tourangelle Roasted Walnut Oil (https://latourangelle.com/product/walnut-oil/) for years and can't tell the difference between it and Mahoney's Walnut Oil. I have done side by side testing and they have essentially the same viscosity, smell the same, looks the same on maple, dries the same, but I haven't tried the Mahoney Walnut oil on a salad yet. A few years ago the cost of the La Tourangelle Roasted Walnut Oil was about half the cost of the Mahoney product, but the cost difference is closing. The thing that I like about La Tourangelle Walnut Oil is that it is premium quality expeller pressed oil and no additives.

[Richard Coers]

I just use Boiled Linseen Oil for food finishes. You can also use it with shellac to get a more durable finish that is also food safe. Friction polish (BLO, DNA, Shellac) is my go-to for food grade. And it's also a great general finish too.

Commercial boiled linseed oil is not considered to be food safe by everyone. There are metallic driers added to aid curing, often cobalt manganese salt.

[Edward Weingarden]

I just use Boiled Linseen Oil for food finishes. You can also use it with shellac to get a more durable finish that is also food safe. Friction polish (BLO, DNA, Shellac) is my go-to for food grade. And it's also a great general finish too.

I would suggest researching the process of making BLO. The things that I have read say that chemical driers are added during the production process. Some people feel that once any finish has cured, it is food safe, but that's a topic of much debate. If one wants to use linseed oil, Tried & True makes a polymerized linseed oil without additives. The following is from their website:


[*=left]Solvent free, zero VOC’s, and no heavy metal driers
[*=left]100% safe for food contact surfaces

My comments about T & T are for informational purposes only. I have no financial, or other interests in Tried & True.

[Stan Calow]

If the difference is that walnut oil for finishing has been heated to jump start polymerization, then one could theoretically do that at home as well, right? I've used culinary w-o for years for kitchen tool handles and cutting boards. Just checked a couple - haven't noticed rancid smell being a problem. I think it gets worn off the surface by hand contact and rinsing.

Sometimes I think food-safe means different things to people. I can see that one concern is that the finish will leach organics or metals into the food, but the other concern is that you'll actually scratch and scrape some finish off into the food with your utensils. So saying "all finishes are food- safe when dry" is misleading, I think. I thought that some of those "food-safe" finishes like Behlens were linseed oil but without the metal driers.

BTW, I did a test once with walnut oil and BLO on a piece of glass and the w-o was still wet when I gave up after a month. I even tried a sample with some japan drier added, that didn't make a difference.

[Bill Boehme]

Here are a couple posts on the subject of walnut oil posted on the AAW forum by Rob Wallace. Rob is a professor of Plant Systematics and Evolution, Botany, and Taxonomy at Iowa State University.

https://www.aawforum.org/community/index.php?threads/walnut-oil-finish.6212/#post-50100

and

https://www.aawforum.org/community/index.php?threads/walnut-oil-finish.6212/#post-50264

[Brian Deakin]

I am not sure if this helps below are the MSDs. for Mahoneys and Doctors walnut oil

http://www.doctorswoodshop.com/Portals/0/MSDS_Sheets/DWS_Walnut_Finishing_Oil_MSDS.pdf?ver=2019-09-24-144519-087

and
https://www.highlandwoodworking.com/msds/Mahoney-Walnut-Oil-msds.pdf