Choosing The Right Sanding Techniques
Finishing a woodworking project is usually done by sanding. Sanding can either be done manually or with a power tool. Knowing which specific sandpaper to use for a particular project is important; otherwise, the project you worked so hard to complete might get ruined.
Selecting the Appropriate Sandpaper
Identifying a sandpaper is done by its grit number. When you’re looking to buy sandpaper, a store attendant will always ask you about the grit number you need. It’s important to remember that there are different textures of sandpaper available. Lower grit numbered sandpapers are coarser while high-numbered ones are finer. Sandpapers ranging from a grit number of 40 to 60 are classified as coarse since the abrasive particles for every square inch are more concentrated. Sandpapers with a grit number from 80 to 120 are considered medium, while those that range anywhere from 150 to 180 are fine. Aside from these, there are also very fine grits, extra fine grits, and superfine grits available. Other woodworkers prefer doing all the sanding work using a super fine sandpaper because they’re afraid to scratch too much of the wood away. Most of the time, doing this method is okay, but I can be quite inefficient since some portions of the wood may need a coarser sanding.
Essentially, the three methods of sanding are manual, using a block, and by utilizing a power tool. Most projects only need one sanding method, but there are some that may require you to employ two methods of sanding. This usually happens when the first method resulted in unwanted scratches on the surface of your material.
Manual sanding is particularly used for curved surfaces only. If a manual sanding method is done on flat surfaces like drawers and tabletops, it may result to hallowing. For difficult-to-reach areas of your project, this type of sanding is highly preferred. In order to sand manually, simply take a piece of sandpaper and fold it three times. Firmly hold the sandpaper while you work on the surface of the material.
Block sanding is somewhat related to hand sanding with the exception of using a block of wood. To do this method, you just wrap the sandpaper around the block of wood. This will give you more leverage while you sand.
Sanding Using a Power Tool
There’s a variety of power tools used for sanding but the most popular one is the random orbital sander. This power tool is very efficient in removing scratches which resulted from manual sanding. If you want a good finishing tool, this is a great investment.
Deciding on How Much Wood to Sand
Now that you know how to select the right sandpaper and how to sand properly, how do you know if your sanding is sufficient enough? This is typically something that you learn from experience, but there are two methods you can use. Before you proceed to use any of these two methods, you must be sure that your project is free from imperfections and scratches. If everything is alright and there are no imperfections, only then can you proceed.
Reflected Light Method
Place your project at a low angle with reflected light shining on it and observe. Doing this method can allow you to look at the surface better, making it easier for you to notice specific areas where more sanding may be needed.
Denatured Alcohol Method
This method requires you to wet your project with denatured alcohol and then inspect it through the light. The liquid will allow the grains to rise and you will be able to see the areas that need additional sanding. As a substitute for denatured alcohol, mineral spirits like paint thinner can also be used. However, if the project needs to be finished with a water-based agent, avoid using mineral spirit as the oil from the spirit will bead up.
After Sanding, What’s Next?
Putting the finishing touches right after sanding isn’t recommended. The first thing you have to do is to get rid of all the sawdust, regardless of how fine they may be. Using a small vacuum for this purpose is a good trick. Most of the time, this method is sufficient enough. But if this fails to do the job, a piece of cloth damped in denatured alcohol will save you. Simply dab it on your project and the alcohol will work to remove the sawdust remains.