No wood project is done until it has been finished…with a sander. A sander is the only way to put the final touches on almost any DIY project.
Types of Portable Sanders
There are four main types of sanders to consider, all of which serve their own purpose. You can narrow down your sander choices by asking yourself some basic questions and learning what features you need in your sander.
Typically the most powerful, belt sanders are high-speed, flat-surface sanders designed for rapid finishing of floors and other large surfaces because they remove a great deal of material in minimal time. They do an excellent job of leveling and smoothing large, rough-sawed knotty or warped boards and are also ideal for quickly removing paint and sanding metals or tile. So, if you're working on a project that requires smoothing out large surface areas, stripping paint or removing rust, the belt sander is an ideal choice. Replaceable belts are available in various grits.
Finishing or Pad Sanders
The most popular and versatile type of sander and built for smaller jobs, finishing or pad sanders come in handy when space and size are a concern. Given the proper sandpaper and power rating, finishing or pad sanders are capable of providing a smooth finish over a variety of woods. They employ squared-off pads to produce a smooth, even finish on a variety of woods. They can also sand or remove paint on finished surfaces. A finishing sander is needed when it's essential that the sandpaper move only along a given plane.
Different models perform these tasks by utilizing the following types of sanding motions:
- Straight-line uses a back-and-forth motion (similar to hand sanding) to produce a fine finish. It’s perfect for sanding in tight areas and for rough sanding, such as refinishing or restoring furniture. Sand with the grain for smooth finishes, against the grain for rough sanding.
- Orbital operates in a tight circular motion that is best applied to finish sanding and limited paint removal.
- Dual motion gives the user the ability to choose between straight-line strokes and orbital motion depending on the task.
- 3D sanders look and work much in the same manner as the old electric shavers that relied on floating discs to accurately follow the contours of the face. It utilizes three rotating discs set in a triangular pattern, has a variable speed capacity of 800 - 2600 rpm and sands both concave and convex surfaces.
Whether your project requires rough-sanding, finish-sanding or preparing wood for staining, consider the orbital sander due to its versatility. Random orbit sanders move the pad in a circular motion to help prevent gouging and simulate hand sanding to produce finishes that are virtually free of swirls, scratches and burns. They typically remove stock up to 50 times faster than conventional sanders. While very aggressive, random orbit sanders are excellent in preparing a surface for finishing. They are commonly used by trades people and remodelers because this sander can remove materials quickly and leave a smooth finish. Sanding something with opposite grain faces typically demands a random orbit sander.
Detail or Contour Sanders
Detail sanders have uniquely shaped heads geared for smaller, tighter and more detail-oriented projects and hard-to-reach places that would otherwise present a challenge to belt or orbital sanders. They utilize a very small orbital-vibrating motion to remove stock. Detail sanders can smooth bare wood, remove light rust from intricate surfaces, and remove paint, varnish, wax and polish from hard-to-reach surfaces. Detail or contour sanders are great for corners.
Sanders that utilize straight-line motion are rated in Strokes Per Minute (SPM) - the number of back-and-forth strokes the pad makes in a minute. Orbital motion sanders are rated in Orbits Per Minute (OPM) - the number of times the pad completes a full circle in a minute. Dual motion sanders are rated as OPM/SPM. Detail sanders are typically rated as OPM or SPM, depending upon the model.
Faster speeds of 10,000 OPM/SPM or more are generally best for fast, smooth finishing. Slower speeds are better if you intend to use the sander for heavy stock removal on wood or when smoothing fibreglass or plastic.Sandpaper
Choosing the right sandpaper can be a challenge because there are so many types and sizes available. Some of the key ways to differentiate sandpaper are grit and coating/density.
- Grit: Sandpaper typically ranges from very coarse (20 to 40 grits per inch) to very fine (600 grits per inch) and comes in a wide variety of materials. Grit refers to the size of the abrasive particles on the backing. Sandpaper can be generally categorized as follows:
- Coarse grit = 20, 36, 40, 50 and 60 grit
- Medium grit = 80, 100 and 120 grit
- Fine grit = 150 and 180 grit
- Very fine grit = 220, 320 and 600 grit
- Coating/Density: The sandpaper's coating/density indicates the closeness of the abrasive particles on the backing. Closed-coat indicates that the particles cover 100 percent of the surface backing. Closed-coat products tend to clog quickly on soft material and generally should not be used for fine sanding. Open-coat covers approximately 50 to 70 percent of the surface backing. Open-coat products typically do not clog as easily, making them the paper of choice for sanding softer materials, and for both rough and fine sanding.
Allows you to change speeds according to the material and your comfort level.Handle
The handle style affects your comfort and ease of control. Most models feature a comfortable palm grip at the top of the sander. Some finishing and random orbit sanders feature two-handed grips. Whatever handle style you choose, it should not be an effort to hold and operate the sander.Power
The power in a sander's motor generally affects the efficiency of the tool and the amount of time it takes to get the job done. Pad speed varies for different types of sanders and also determines the type of finish the sander will apply to the workpiece.Interchangeable Sanding Pads
A variety of pad shapes allow you to work on different types of projects.Belt-Alignment System
Reduces your need to periodically adjust the belt's alignment.Belt-Release System
Allows you to change belts or shift sandpaper grits easily.Memory Systems
Eliminates belt wandering and keeps the belt running straight.Dust Collection
Reduces the considerable amount of dust made by these tools and saves on clean-up time.Dust-Sealed Switches
Provide cleaner work environments and longer life for the sander.Counter Balance System
Reduces vibration and improves performance of the sander.Automatic Brake Pads
Control the sanding speed for optimum performance.