Sanding is a vital part of woodworking as it allows you to smoothen out any roughness that may appear due to the imperfections of the wood or due to the processes you apply to it as you build your project.
As it’s possible to remove most flaws easily with sanding, it’s a crucial skill that every woodworker should learn at some point – and while sanding looks simple from the outside, there are a few intricacies that require expertise; such as material and grit selection.
While sandpaper is the first thing that comes to mind when we talk about sanding, it’s not the only material you can use to sand wood. Steel wool, a lesser-known material, is also a fantastic option, and it can even outperform sandpaper in some situations.
So, how do steel wool and sandpaper compare to one another?
Steel wool and sandpaper are two entirely different abrasives with different qualities. While sandpaper is a flat sheet produced by combining certain abrasive minerals, steel wool is a flexible product made of low-carbon steel.
Even though they work in the same way for sanding as they both remove parts of the wood by cutting into its surface, there are cases where one is more suitable than the other due to the different qualities they bring.
Knowing the strengths and weaknesses of both of these abrasives is the key to making the right decision, so, without further ado, let’s get down to the details of how they separate from each other and how you can choose the right one for your project.
Steel Wool vs. Sandpaper – Making the Choice
Sandpaper is a material that we are all familiar with as it’s the first thing that comes to mind when we think about sanding. With plenty of grits to choose from, there is a proper sandpaper choice for all sanding jobs.
On the other hand, using steel wool for sanding isn’t something that you hear a lot, mostly because sandpaper gets the job done in almost all cases.
That being said, there are certain unique qualities that steel wool can offer, but due to it not being as popular as sandpaper, these qualities are often overlooked or not known.
As making the right choice between the two comes down to knowing the advantages and disadvantages of both, it’s time to take a deeper look into what these abrasives can and can’t offer.
Steel wool, as the name suggests, is made from low-carbon steel.
The main benefit that comes with using steel wool is its flexibility. While you can only find sandpaper in the form of flat sheets, you can compress, expand, and mold steel wool to any shape you want.
This flexibility allows you to easily use steel wool in areas where you would have trouble reaching with sandpaper.
On the other hand, the main disadvantage of steel wool is the fact that it can rust. While you may think that this isn’t much of an issue as you can refrain from getting it wet, the problem is mainly caused by small pieces of steel wool that get stuck in the wood during the sanding process.
This disadvantage makes it a bad idea to use steel wool on water-based finishes as there is almost no escape from having to deal with rust problems.
Sandpaper is made by gluing a mixture of abrasive chemicals onto a sheet of paper or cloth.
The main advantage of sandpaper is that it doesn’t leave any residue behind that can cause a problem later, unlike steel wool or abrasive pads.
On the other hand, the main disadvantage of sandpaper is that it’s highly inflexible, which makes it quite hard to use on some surfaces where the working area is limited.
Can Steel Wool Be Used in Place of Sandpaper?
You can use steel wool in place of sandpaper without any problems in all cases except sanding water-based finishes.
Due to the small pieces of steel that get left behind after sanding with steel wool, it’s often considered a bad idea to use it on water-based finishes as the steel pieces become rusty when they come into contact with water.
That being said, if you would really like to use steel wool on a water-based finish, you may be able to avoid the rust problem by giving the finish enough time to completely dry.
What Grit Sandpaper Is Equal to Steel Wool?
The grits of steel wool are measured differently than sandpaper, which may make it hard to find steel wool that is of equivalent grit to the sandpaper you are looking to replace.
While it’s not possible to get an exact conversion between the grits of sandpaper and grades of steel wool, you can follow the list below to get a close approximation and find out which steel wool would suit your project the best.
- 4/0 (#0000) steel wool <-> 300-600 grit sandpaper
- 3/0 (#000) steel wool <-> 280-320 grit sandpaper
- 2/0 (#00) steel wool <-> 150-220 grit sandpaper
- 1/0 (#0) steel wool <-> 100-50 grit sandpaper
- #1 steel wool <-> 80-120 grit sandpaper
- #2 steel wool <-> 60-80 grit sandpaper
- #3 steel wool <-> 40-60 grit sandpaper
- #4 steel wool <-> 30-40 grit sandpaper
Please note that these conversions aren’t final and may show differences between different steel wool brands.
Can I Use Steel Wool to Sand Polyurethane?
You can use steel wool to sand polyurethane without any issues, but you may face rusty spots due to the flakes of steel that are left behind by the steel wool if you are using a water-based polyurethane.
As a rule of thumb, it’s a better idea to use sandpaper to sand between coats if you use a water-based poly to eliminate any risk of rust-related problems later on.
Does Steel Wool Scratch Wood?
Just like sandpaper, steel wool can also scratch and leave marks if you sand incorrectly, especially with lower-grade steel wool, which acts similarly to lower grit sandpaper.
To ensure that you don’t face this problem, always sand in straight and long strokes with the grain of the wood. Try to apply an equal amount of pressure throughout to ensure that the surface of the wood becomes completely smooth after sanding.
Both steel wool and sandpaper are viable abrasives for sanding – and as both of these materials come with their own strengths and weaknesses, choosing the one you will be using comes down to your project and personal preferences.
Even though it doesn’t get as much credit as sandpaper, there certainly are areas where steel wool will make your life easier if you decide to give it a try!