There are many different ways to change the color of wood and the most common is by coating the wood with some sort of a color stain or even a color dye but you can also change the color of wood by using simple household products that change the color of wood by reacting to the tannin in the wood.
Anyone who has ever made wine, especially from scratch, will have heard of tannin, which is just a mild acid that is contained in many wood species of plant, including grapes and vines. In winemaking the tannin is added as a power to enhance the taste of the wine.
Watch it on Youtube: https://youtu.be/6IFHod0Rr00
In woodworking, we can use that same tannin in wood to change the color of the wood by altering it chemically and allowing the tannin to change color during the process.
Different woods contain different amounts of tannin and tannin can even vary slightly within the same tree and within the same species of trees. This variance is what helps to give wood it's distinct look by not being the same consistent color as you would get with paint for example. The process of colorizing wood using iron that has been soaked in vinegar is not new, it has been around as long as I can remember, but it is not used much anymore but still has some uses and remains another interesting way of coloring wood.
The process is easy and simple and from what I have seen is not all that strict in quantities so is quite forgiving. The formula that I used is easy 12 fluid ounces of vinegar and one bunch of fine steel wool. Soak them together overnight in a glass or plastic container, making sure the steel wool is fully submerged so that it won't begin to rust by having parts of it exposed to air, and the next day it's ready to use. For this same reason, it's probably a good idea to make sure you are not wearing any good clothes because even a drop of this solution on some fabrics will change the color forever.
The solution is inexpensive to make but seems that it oxidizes fairly quickly so you probably want to either use it up quickly and/or make smaller amounts so that you can use up what you make before it gets old. As you can see in the video, I did use an earlier batch that was about 4 days old and it was already turning to color or rust, because it was oxidizing and it worked OK, but there was ever so slightly a minor color change, so I would expect as the solution oxidized more and loses it potency it would have less of an effect on the tannin and therefore less color change intensity.
Just another woodworking process that may have used in the process of coloring wood.
Woodworkweb Amazon Affiliate Store - https://www.amazon.com/shop/woodworkweb
Copyright Colin Knecht