Wetting wood before sanding is the most common thing that everyone does.
But thinking about the outcome like is this a feasible approach to wet sand? And what are some circumstances in which the process becomes much more necessary and when dry sanding is just fine?
Let’s talk about it.
Yes, you can sand on slightly damp wood as long as your intention is just to wipe some fiber grains off the wood, to get a better smooth to your surface when you apply a finish next time, in this way the fibers will not rise again. Water or any liquid works as a lubricant that raises the grains on softwoods so that sanding over them clears them all.
Although this is called sanding for refining a wood surface, the main point to talk about there the wood should not be too wet if so then you will have to choose a wet sand grit paper, this is a type of sandpaper that soaks up some amount of moisture while also making the upper surface smoother. However, it depends on how wet the wood is, the method only works fine with wood that is not thoroughly damp.
In the case of sanding a dry wood to prepare it for staining, (Talking about softwoods like pine, and fir, cedar). Then before you put sand grit paper onto it, it’s better to put some water on it and then apply it to sand. Make sure you take off the fibers thoroughly for this you will need to apply sanding for 2 to 3 minutes and stop when you notice the surface is clear.
Alternatively, you can apply dry sandpaper without using any lubricant, on a plank of completely dry wood. (Talking of hardwood like walnut, maple) these woods don’t have many fibers if they’re stained or just naturally very smooth. Applying a sand grit paper onto them creates some tooth’s surface so when applying stain, or paint color, for instance, it will hold onto the tooths and last longer- eventually give a smooth result. Additionally, in case you see some grains rising, sanding after finishing will do the work just fine. There’s not a big issue there.
So to be concluded-
To get a better finish-
If the wood is fresh, newly cut from a tree; then it must be dried throughout that can take a year so the fiber grains can be taken off. As freshly cut woods have some natural moisture underlying their coats with time that rises resulting grains growth, so it’s harder to get a smooth finish on them even you finish the top coat.
Only a thoroughly dried wood can be sanded to get a smooth finish by dampening some amount of water on it. This is the best way and mostly woods placed inside sits in this category.
Lastly, partially dried wood can be sanded but soon after it is thoroughly dried the fibers will rise hurting the finish due to in dryness that wood fibers becomes sticky. Mainly the outdoor woods that had been affected by rain or humidity sits in this category.
Why do many carpenters sand on wet wood?
The main reason why do people sand is because of the thought that is “watering over a surface rises grains” which is partially true. In general, if you look for many wood experts don’t do wet sanding as they know it a lot depends on the types of wood as well the needs.
Getting a smooth finish is not all about sanding better, but the types of wood should be in mind as well the condition of the wood. If it has been soaked in heavy rain for years by sitting outside. Then it’s hard to get an even finish no matter what technique you are apt for unless you dry it out.
Secondly, it’s actually an easy way to wipe off any dirt stain by applying some water and rag it than using dry sandpaper. So, that’s also the reason to count in people usually find it easy.
When to dry sanding?
And you want to refine it for some reason. The dry sand will create some teeth by turning the smooth surface into somewhat feel rough such that no matter what you’re going to apply onto will stuck onto it. Otherwise, if you don’t do this, perhaps the stain you will apply onto it will slip off soon.
Secondly, dry sanding also comes in handy when there are multiple boards attached to create a larger piece. And for sure the surface will be uneven, so to get them balanced, making them equal from all over, dry sanding with a power tool like a sand gripper can do the job just fine.