What Is Wood Hardener?
Wood Hardener is typically a liquid material. The liquid is often made of a cross linking polymer and film forming agents.
Basic Wood Hardeners can be made of acrylics. Heavy duty options can be found in 2 part epoxy versions. Each can have their benefits and detractors depending upon the intended use.
What Is The Purpose Of Wood Hardener?
A Wood Hardener is designed to soak into wood fibers and bind. This binding process gives a few different benefits.
You gain the ability to prevent further rot on the portions of wood on which it is used. Additionally the wood gains more strength than it previously had.
A barrier is formed that also prevents further penetration by the elements. Note that your mileage may vary from product to product when continually exposed to the elements.
Does Wood Hardener Give Real Strength To The Wood?
The short answer is yes as I described within the purposes of this product. Yet it should be noted that the amount of strength gained is relative.
In of itself the Wood Hardener is a supplement to add strength to wood, not the source of it. If a piece of wood is already too far gone the hardener will not be enough to sustain it.
Therefore the degree by which you gain strength will be relative to the present state of the wood. In cases where you are bonding splits or smaller portions of rot it will excel.
In cases where the Wood Hardener will be required to support the primary load placed upon the wood it will be far weaker. Choose products according to the needed application and remain within realistic parameters.
Can Wood Hardener Be Used On Wet Wood?
No do not ever use Wood Hardener on wet wood. In the event that you do this be aware of what you are inviting.
Moisture when trapped will continue to rot and weaken the wood. In turn it will also work against the hardener and its ability to bond with the fibers.
There is nothing to gain but everything to lose when applying to wet wood.
Can You Paint Over Wood Hardener?
The short answer is yes. Look at the product you select and pay attention to instructions. Acrylic when compared to epoxy binders may have different requirements.
There may also be cases where special processes are required depending upon your application to the environment. Outside structures will need more attention than interior for example.
What Is The Best Wood Hardener?
None should be called the best. Rather the question should be, what Wood Hardener is best for your application?
When filling things such as knots or small splits a Minwax application may be all that you need. JB Weld on the other hand has been used by many contractors for fixes on construction sites.
Unfortunately there is no way for me to clearly define which is best. Abatron Liquid Wood for example is a 2 part epoxy that has a 30 min work time but is great for preserving outdoors and supporting structures.
JB Weld would be more of a general purpose application. Then the Minwax line I would consider for many small projects or fixes.
These are among the more common for the general public to use without getting into more exotic products.
How To Use Wood Hardener In Wood Art?
Now we arrive at my key purpose for this article. As a wood artist I do run into situations where Wood Hardener is needed for wood art.
We arrive at a complicated issue for now more than structural integrity becomes the issue. Visual aesthetics also becomes critical.
There are two keys to keep in mind when using these products with wood art. First, use a low level of viscosity when you simply wish to coat over a surface.
Secondly, use a high level of viscosity when you wish to mold, shape, or fill holes within the wood. These two keys will help you as you work with your project.
Visually other factors come into play. The product must be able to accept paint or stain, or be able to be applied over paint or stain.
With painting, most wood hardeners can easily be painted over much like how you would paint raw wood. Sanding and then some primer and then paint will usually take care of the project.
Stain on the other hand is a separate world. When stain is applied to wood the color can vary from edge to edge. Add in another product such as wood hardener and the variables shift wildly.
Many products will tell you that they can be stained. I will tell you that while they may accept stain, the color variation can become quite noticeable.
The Trick Of Staining Over Wood Hardener
I will give you which product I have had the most success with in a moment, first let me give you what is so challenging. Within wood art we always wish to maintain consistency of color allowing the natural grain to define transition.
In other words, if the grain color shifts then this is a natural transition which the stain will enhance.
What I have discovered is this, wood species + wood hardener + wood stain = yield in color. Change any of these variables and the outcome can change sometimes dramatically.
Unfortunately the formula still is not this simple. Within the wood species exists spalted variations and how prominent the grain definition has become.
An example of this can be seen when comparing Maple to Ambrosia Maple. While the species is still Maple, the differences between these two in grain color and depth are exceptionally different.
In short, it may require that you conduct some experimentation for wood art purposes. Typically you will find 2 to 3 different products per species that will accept stain color which work well.
My general catch all that seems to do well are Minwax products. Indeed I know these are not the “best” or “strongest”. Yet within wood art typically wood hardener is never used for structural intent.
Visual aesthetics is most often what I am after. Minwax it seems is more consistent in being able to provide the mix of what I need in my work.
Which of their products to use again should be based upon need. They offer a pretty wide degree of application which can range from acrylic to epoxy solutions in wood hardeners.
A Cheat Or Trick When Using Wood Hardener
Years ago I began to use wood dust as a filler. When working on a wood art project I would collect the dust debris from my sanding.
Most sanders have a bag attachment which makes this easy. I would bottle the dust based upon the wood species, label it, and keep it. Why?
When you use this dust to fill cracks, polyurethane acts as a binder. The color will easily match the wood I have used as it is of the same species.
So how does this work with Wood Hardener? Obviously when using these products you want the surface clean and debris free.
In the case of small cracks or holes when using the wood dust it is perfectly fine. These are the natural wood fibers from the same species of wood.
If anything it gives more body for the Wood Hardener to bond with. This also allows for greater ease of maintaining natural color or consistency of color when staining.
Note that this method is great for smaller issues in art where you wish to blend transitions, lines, or imperfections. You do not wish to fill a quarter size hole with dust and then fill it with wood hardener.
If you seek to achieve this then you will need to look at epoxy resins designed for that kind of application. Most often these are used in making tables or encasing exotic pieces of lumber.