Tung oil

  • Hey Guest, For sale we have Hultafors Outdoor Knives with Firesteel PLEASE LOOK HERE for more information or use the Pay Now button in the sidebar

TLM

Native
Nov 16, 2019
1,494
646
Vantaa, Finland
In most vegetable oils there is some water included, about 2/1000 in rape seed oil and about 4/1000 olive oil. That water plays a part in many processes that can spoil the oil, by making the pH low enough most of that is prevented and citric acid is also an antioxidant besides olive oil with added lemon is pretty good.
 

Robson Valley

Full Member
Nov 24, 2014
8,784
1,730
McBride, BC
The heat treatment uses Charles' Law of Gas Physics. There is next to no invocation of any chemistry. I've used the same principle to waterproof wooden dishes with beeswax.
 

Broch

Full Member
Jan 18, 2009
4,396
3,612
Mid Wales
As we've discussed on a number of previous occasions, man has used a combination of vegetable oil and beeswax for thousands of years. The relatively recent research into the antibacterial and antifungal properties of beeswax may well explain the thousands of years of successful use.

Most of the rest is just marketing :)
 

Paulm

Full Member
May 27, 2008
1,091
175
Hants
As we've discussed on a number of previous occasions, man has used a combination of vegetable oil and beeswax for thousands of years. The relatively recent research into the antibacterial and antifungal properties of beeswax may well explain the thousands of years of successful use.

Most of the rest is just marketing :)
Although beeswax has a very low melting point and will leach out into hot food or liquids. Unlikely to do you harm though, beyond flavouring the food and leaving the wood needing retreatment :)
 

TLM

Native
Nov 16, 2019
1,494
646
Vantaa, Finland
Although beeswax has a very low melting point and will leach out into hot food or liquids. Unlikely to do you harm though, beyond flavouring the food and leaving the wood needing retreatment
Some people eat it, I have tasted it and it has just now taste so I don't think adding it to your whatever will have any effect.
 

Robson Valley

Full Member
Nov 24, 2014
8,784
1,730
McBride, BC
Almost all biological waxes melt at temperatures close to 60C. The beeswax cannot leach out into food any more than the oil does.

I buy and eat comb honey. I like both the taste and the texture. The bees do not like to work the little wooden boxes. So as a premium commodity, the price goes up. Memories of my childhood, far away.

Here's the process. These are physical facts, not opinion.

Preheat the kitchen oven to 170C/340F or so. No hotter necessary.
On a mesh cake rack over a sheet pan, slather the wooden utensils, dishes, etc with oil or melted beeswax.
Into the oven for 3 minutes and 30 seconds by the clock. We aren't making chips.

OK. Out of the oven to cool, take a look:
Charles' Law predicts that heated air expands. Fact.
You see that as strings of little bubbles of wood air in the liquid oil/wax.

Charles' Law predicts that cooling air will contract. Fact.
So as the wood cools, the remaining wood air contracts and sucks the oil/wax down into the wood. Brush with more oil if you feel like it.

That's done for keeps. Boiling soup is approx 100C. That isn't hot enough to move the oil in the wood. Hot dish water can't move the oil finish.

As a note added in proof, many old wooden spoons are blackened from heating and sucking in food juices as they cool. Those decompose like the bottom of a compost box. It's just a physics trick you can take advantage of.

Here's an old pic of the production.
 

Attachments

  • BirchB.jpg.jpg
    BirchB.jpg.jpg
    114.4 KB · Views: 3

Paulm

Full Member
May 27, 2008
1,091
175
Hants
So what is the point of using beeswax if it leaches out in hot food or liquids ? Why would you bother ?

Why would you not just use pure, polymerising tung, walnut or linseed oil instead ?

I honestly don't understand what folks have a problem with here, it's a well established, accepted and proven approach in handcrafted food related production, simple and effective.
 

Paulm

Full Member
May 27, 2008
1,091
175
Hants
Almost all biological waxes melt at temperatures close to 60C. The beeswax cannot leach out into food any more than the oil does.

I buy and eat comb honey. I like both the taste and the texture. The bees do not like to work the little wooden boxes. So as a premium commodity, the price goes up. Memories of my childhood, far away.

Here's the process. These are physical facts, not opinion.

Preheat the kitchen oven to 170C/340F or so. No hotter necessary.
On a mesh cake rack over a sheet pan, slather the wooden utensils, dishes, etc with oil or melted beeswax.
Into the oven for 3 minutes and 30 seconds by the clock. We aren't making chips.

OK. Out of the oven to cool, take a look:
Charles' Law predicts that heated air expands. Fact.
You see that as strings of little bubbles of wood air in the liquid oil/wax.

Charles' Law predicts that cooling air will contract. Fact.
So as the wood cools, the remaining wood air contracts and sucks the oil/wax down into the wood. Brush with more oil if you feel like it.

That's done for keeps. Boiling soup is approx 100C. That isn't hot enough to move the oil in the wood. Hot dish water can't move the oil finish.

As a note added in proof, many old wooden spoons are blackened from heating and sucking in food juices as they cool. Those decompose like the bottom of a compost box. It's just a physics trick you can take advantage of.

Here's an old pic of the production.
Oils don't leach out when they have polymerised, you seem to be unnecessarily complicating something very simple, don't know why :)
 
  • Like
Reactions: Kepis

Robson Valley

Full Member
Nov 24, 2014
8,784
1,730
McBride, BC
They do not need to polymerize in less than 4 minutes. They don't polymerize like a plastic. When they oxidize very rapidly, you see a fire.
I don't see a pot of hot chip oil polymerize in 4 minutes. Charles' Law takes all the guess-work out of a fast and effective permanent finish for wooden kitchen utensils. No need to invoke any chemical reactions.
 

Robson Valley

Full Member
Nov 24, 2014
8,784
1,730
McBride, BC
The central concept is Charles' Law. A slick little piece of physics that beats any and all room temperature superficial coatings.
If there are any chemical side effects in less than 4 minutes, they can be ignored as insignificant.
 

C_Claycomb

Mod
Mod
Oct 6, 2003
6,256
1,253
Bedfordshire
I have had spoons that were treated with room temperature olive oil where the oil has left the wood. I have my own spoons where I have room temperature applied pure tung oil, no thinners, and allowed to polymerise and the oil has left the wood in some places, notably the end grain where the utensil meets the pan. Those areas have absorbed from the food cooked.

Pure tung is quite viscous, more so than linseed and way more so than the mixed blends that include thinners. As such it does not soak in very well at room temperature. I don't really want to use thinner on eating utensils, so using heat to thin the oil and encourage it to be drawn into the wood makes sense.

Oven heat applied tung oil....so far so good, but need more time to see how much difference it makes.
 

TLM

Native
Nov 16, 2019
1,494
646
Vantaa, Finland
Did some searching on olive oil, it is fairly reactive just 14% saturated fatty acids. It apparently does leach out of the wood when not crosslinked or chemically bonded there, still not all of it, even hexane did not get all out. But the impregnation was done first vacuum and then 7.5 bar pressure so not really your standard home treatment. It does not easily crosslink without catalysts, cobalt octoate being one of the most common previously but now being phased out with other organometallics.

Looks like a fully crosslinked oil would be be your best bet. Some of the modern catalysts apparently are quite non toxic. Vacuum treatment would be way better than anything achieved with gas laws, though they have they place in achieving bubbles lacquer layers. Some terpenes might be used for thinning oil if heat is not enough, alcohols apparently do not work at room temp.
 

Hultafors Outdoor knife for Sale

We have a a number of Hultafors Outdoor Knives with Firesteels for sale.

You can see more details here in this thread OUTDOOR KNIVES The price is £27 posted to the UK. Pay via the paypal button below.