An essential part of a woodworking project is sanding the wood to create a smooth surface before applying a finish. We use sandpaper of various grits. Sometimes, you may need to wet the surface to produce specific results.
Can you still sand wood while it’s wet? This is a much asked question and the answer is yes, but then, it depends. If not done properly, you may not get satisfactory results. But using the correct method can be beneficial. However, there are both advantages and disadvantages to sanding wet wood.
Background
Usually, you can sand wood with satisfactory results without having to wet the surface of the wood. Sometimes, wetting the wood can be beneficial but it depends on the method and whether you need that level of finish. However, it is not always mandatory.
There are two different types of sanding that you might perform on wet wood. In the first instance, you may use a dry sander to smoothen the surface of the wood exposed to rain or the wood might have a high moisture content.
With cases where the wood has a high moisture content, you would use a dry sander, and perhaps wait a few days until the wood becomes a bit drier. You might not get a smooth finish while sanding wood that is wet in the first instance. This method is OK to use in general construction, where you don’t have to be too concerned with aesthetics.
If you want to add a finish to fine furniture or interiors, then we would not recommend the above method. If you want a smooth surface using this method, you would do well to ensure that the wood is completely dry.
The dryness of the wood for sanding is a critical factor. You need wood with a moisture content of 9% or below for it to be sufficiently workable for dry sanding. You would probably use your sander for trimming the wood to specific dimensions like to accommodate hinges on a door frame.
With wet sanding, you work on the natural wood fibers that get raised. We take advantage of this phenomenon to smoothen the edges and the excess parts of the wood. With this type of sanding, you will probably not get a smooth enough surface to apply a finish like a varnish or lacquer.
Wet Sanding vs Dry Sanding
The two ways that you might sand your wood are through either dry sanding or wet sanding. With each method, we get specific results, you need to know what type of method is the most appropriate for the task at hand.
Regarding the question of whether you can still sand wood while it is wet, the answer is yes. However, the way the wood is wet depends on how you deal with it. You may use a sander on completely dried wood, or on wood left out in the rain.
Either way, you will use a dry sander but you will get a rougher finish if the wood is wet. You can get a smoother surface when the wood is completely dry.
Wet sanding is a process that involves wetting the wood in a controlled way as you sand it. It produces a much smoother surface than you would get from dry sanding. But there are some specific procedures that you need to follow.
Let us then consider each type of sanding to get a better understanding of which one to use and when.
Dry Sanding
We usually do dry sanding with an electric sander. This method of sanding produces a considerable quantity of sawdust. You may do dry sanding if you want to reduce the dimension of the wood to a particular size to suit your requirements.
We do dry sanding typically on wood that has a 9% or less moisture level. With dry wood sanding done by an electric sander, you may not get an extremely smooth finish. Dry sanding involves slightly rougher grit sandpaper.
Wet Sanding
Wet sanding is different from dry sanding in many ways. To begin with, you will not use an electric sander. Also, the sandpaper you use is extremely fine grit and may range from 200 grit to 2000 grit.
Usually, we soak the sandpaper for about 24 hours before commencing the job. If you are short of time, you can soak it for a shorter period. The exception is if you have a low-tier job at hand.
In such a case, you can add a few drops of water to your sandpaper or wood surface to do wet sanding. The result is that you get a smooth finish, much smoother than from dry sanding.
You must use limited water while wet sanding wood. If you use more water, you stand the chance of saturating the wood. If the wood gets saturated, the wood fibers could expand and stand up even after you’ve finished sanding. It might result in the surface of the wood becoming rough again. You can get the best results from wet sanding while adding a finishing touch to a project.
How to Prepare Wood for Sanding
The preparation to sand wood is as important as the actual process of sanding it. You need to spend considerable time and effort to get it right. If you leave out any steps, you stand a chance of getting unsatisfactory results at the end. Here are the basic steps you should follow:
Allocate Your Location
Allocate a dedicated work location free of disturbance, dust, and traffic. Once you start sanding you neither want to be bothered by others nor do you want to disturb them. Also, the area should be free from contamination. During the process, you’ll have to occasionally leave your wood to dry, so the environment should be dust-free.
Consider Temperature and Humidity
When you apply water to the wood during wet sanding, you need the temperature of the air to be at least 65°F. The humidity should be no more than 50%. With lower temperatures or higher humidity, your project will take longer to dry and could end up looking tacky.
Have Good Ventilation
If you are sanding between coats, then while applying a finish, the volatile substances in varnish or lacqer can generate fumes. Your location should be well-ventilated to allow noxious fumes to escape. Installing an exhaust fan at the location is also a good idea, to get rid of fine sawdust and volatile fumes.
Fill the Cracks, Holes, and Splits
Before you begin sanding give the project a thorough visual examination. Identify holes, cracks, and loose joints and fill them with wood filler. Only commence your sanding operation once the wood filler is dry for best results.
Use Correct Sandpaper
Depending on the job at hand, use an appropriate grit of sandpaper. For fine sanding and wet sanding, you will usually use sandpaper between 200 grit to 2000 grit. Woodworkers popularly use 1500 grit sandpaper.
Use a Felt Block
Another useful tip is that instead of rubbing the sandpaper with your hand, use a felt block. You wrap the sandpaper around the felt block to create a uniform surface of sandpaper. It results in uniform sanding. Felt blocks are inexpensive and easily available online.
Make Adequate Arrangements for Dust Control
Dust is one of the biggest adversaries of woodworkers. It can ruin a particularly good woodworking project, especially while applying final coats. Ensure that you have a robust dust-controlling setup with the right type of dust collectors, brushes, cloths, and rags at the ready.
Conclusion
Coming to the question can you still sand wood while it’s wet? The answer is of course, yes. There is a good case for both dry and wet sanding. The trick is knowing when to apply the respective procedure. It is important to know the fundamentals of sanding to get it right. If you don’t follow the correct procedures, you will never get satisfaction from your woodworking projects.
But if you choose the suitable sanding procedure and use the correct techniques, you can get great results and you can create some outstanding woodworking projects.