Wet Sanding vs. Dry Sanding

Whether wet or dry, sanding is a method used to remove unwanted materials from surfaces. It involves the use of abrasive papers to either smooth or remove unwanted layers from surfaces like floors, metals, walls, wood furniture, etc.

Wet sanding is a process that involves the use of a special kind of sandpaper and water which acts as a lubricant to help smooth surfaces without creating scratches on them.

On the contrary, the dry sanding process does not require water or any form of lubricant. It is a popular kind of sanding where dry sandpaper is used to handle surface imperfections.

The major difference between these two types of sanding is that wet sanding is typically done to achieve smoothness on surfaces and usually comes after dry sanding. While dry sanding is aimed at shaping and removing unwanted layers from a surface. However, both types of sanding are used as a means of surface treatment.

Below is a comparison table for wet and dry sanding

Features	Wet sanding	Dry sanding
Sandpaper	Wet sandpaper	Dry sandpaper
Sander type	Water-resistant sander	Vacuum sander
Requires lubricants	Yes	No
Movements used	Small circles	Straight lines
purpose	For smoothness	To remove layers
Majorly used on	Metals, marble	Woods, plastic
Cost	Expensive	Cheap

Differences between the wet sanding and the dry sanding

There are many differences between the wet and the dry sanding since they are opposite each other, so let’s have a look at some of their differences.

Sandpaper type

There are two types of sandpaper which is the wet and dry sandpaper, and they should be used for wet and dry sanding, respectively. Regular dry sandpaper is not recommended for wet sanding because it will get ruined by the lubricant you apply. Wet sanding requires a special type of paper that is resistant to water and other lubricants. Also, regular dry papers are best suited for dry sanding because it is supposed to heat up while sanding, and you won’t get that if you use the wet paper.

Sander type

A sander is the power tool you attach your sandpaper to before sanding. Just like you need a special wet paper for wet sanding, you also need a special type of sander, one that is resistant to water, for wet sanding. Some of these types of sanders are air-powered, which eliminates the need to worry about water getting into the machine. In contrast, the regular sanding machine will do just fine for dry sanding. No need for water-resistant sanders, no need for air-powered sanders.

The need for water or lubricants

Another thing you need for wet sanding is water or lubricant. Since the aim is to make a rough surface smooth, you need to wet the surface first before sanding. Without the water, the sandpaper can get clogged up with large particles that are being removed, which can, in turn, scratch the surface you intend to smooth. Another thing the water or lubricant does is that it reduces the friction between the paper and the surface for a more smooth finish. This is not the same for dry sanding.

Dry sanding does not need water or any form of lubricant because the paper needs to be harsh on surfaces in other to remove stubborn layers and make even every part of the surface.

Sanding movement

This is one of the detail most DIYers do not pay attention to, they just want to get the paper and scrub the hell out of the surface, or for wet sanding, they apply the lube and focus on scrubbing gently. Well, the truth is whether you scrub gently or with force, you might not get the desired result if you are scrubbing in the wrong direction. So, it is recommended to move the paper in straight lines during wet sanding and to move it in a small circular motion for dry sanding. The reason is that you want to have an even and smooth surface at the end of the sanding. Since dry sanding is usually before the wet sanding, its circular motion will effectively remove the particles. In contrast, the straight-line movement of the wet sanding will reverse the circular marks of the previous pass, leaving your surface as good as new.

Appropriate sanding surfaces

Simply put, wet sanding is best suited for metal and marble surfaces. This is the reason why auto engineers prefer wet sanding for surface finishing other than dry sanding. But dry sanding works well on wood surfaces like decks, floors, and walls, where all the intensity is needed.

Similarities between wet and dry sanding

There are quite a few things that both types of sanding have in common, and these are:

Whether you are wet sanding or dry sanding, you need sandpaper to do so.
Both types of sanding can make a mess of your environment which is evident in the mixing of water with particles in the case of wet sanding or the dust that fills the air for dry sanding; and
If both types of sanding are carried out appropriately, they will both deliver the anticipated result.

Conclusion

From the details above, it is naive to better one type of sanding over the other because they are both needed as long as sanding is concerned with achieving different purposes. The information provided above lets you know which one to do at any point in time to get what you want.

If you want a smooth and shiny surface on a metal or a marble, you should consider wet sanding. It is mostly done manually and with patience, especially if the job is a delicate paint surface. But if you want to remove unwanted materials or even out a wood surface, dry sanding is the best option. It is recommended to use a sander because dry sanding requires a lot of strength and can cause hand pain if it is done manually on a large surface.

It is important to note that you don’t need sand to carry out sanding, so don’t be deceived by the word “sanding.”