Sanding anything by hand is a task that grows old quickly, especially if you need to remove a lot of material. For small jobs, a palm or pad sander is fine, but for a big job — smoothing a rough board, removing an old finish from a flat surface, or sanding a jamb flush to the wall before installing the casing molding — turn to a belt sander.
A belt sander is a portable power tool that has a front and rear pulley two grips, and a platen at the bottom. To install a sanding belt, the front pulley must be retracted slightly, typically by pulling on a belt-tensioning lever. The platen, a metal plate at the bottom of the tool, is where the tool meets the surface of whatever you’re sanding. It keeps the belt, and the work, flat. A belt-tracking knob keeps the belt centered on the platen and pulleys.
Using a Belt Sander
Belt sanders are used to smooth large areas of wood or metal, generally to a smoothness of 60 to 120-grit. For further smoothing, go to an easier-to-control orbital sander. Belt sanders can also be used to remove old finishes from flooring or siding.
Operating a Belt Sander
1. Check that the on switch is in the off position when plugging in the tool, or the tool will take off on you and cause injury or damage.
2. Start the sander with the tool lifted off the surface that you intend to sand.
3. When operating the sander, use two hands. Rest the work piece against a stop (clamped to your workbench or table) to prevent it from being flung backwards.
4. Use long even strokes, overlapping each stroke for even results. The weight of the sander usually applies sufficient pressure to get the job done, but you may apply light pressure to speed things along. Avoid heavy pressure as it slows the motor — and your progress.
5. Sand only in the direction of the wood grain, and keep the sander base (shoe) flat to the work piece.
6. Avoid using the pulley for sanding flat surfaces; it will cause dishing (unwanted depressions).
7. Similarly, avoid tilting the tool to one side or the other. Lift the tool from the work piece before stopping the motor, and be sure the belt has stopped before putting the tool down.
Buying a Belt Sander
Belt sanders are available in several sizes and are normally classified by belt width and length. The smallest I’ve seen is a 2-1/2″ x 14″ unit that weighs less than 5 pounds. The largest hand-held accommodates has a 4″ x 24″ belt. While bigger may sound better, keep in mind that large sanders also weigh more. Heft a tool before buying it and, if possible, do some sanding with it. If the tool is too heavy, you’ll tire quickly while using it.
Opt for a dust collection bag, and make sure it fits tightly to the dust port so it won’t pop off as you’re using the tool. Some ports will hook up to a vacuum hose for even better dust collection. Also consider a tool design that facilitates clamping the sander, business-side, up to a workbench or table. Many sanding operations, especially when the work piece is small, are easier with the sander in a stationary position. Some newer models offer variable speed control for better tool control as you’re making your final smoothing passes. Heavy-duty motors allow you to apply extra pressure to speed the job along, which is especially useful when you need to remove a lot of material from a rough surface. Finally, check the tool’s specifications for noise. Some models are much louder than others. The quietest units come in at about 92 db (decibels).
Belt sanders require cleaning after each use. A paintbrush does a good job of removing sanding dust; a blower works even better. Belt sanders do not generally require lubrication beyond what was applied at the factory. Some belt sanders, however, have brushes (parts that conduct electricity to the motor). Check with your owners manual about recommended hours of operation before having brushes replaced, something that should be done at an authorized service station. Be sure to install sanding belts so they travel in the direction indicated on the belt. Otherwise, the belt’s glued joint will quickly fail. Change the belt once it wears or rips. You can sometimes extend its life by cleaning dust and resin build up with a stiff brush. Another approach is to hold a rubber cleaning block (or the rubber sole of an old sneaker) to the belt with the sander running.
Price range: $50 to $230
– Only hold the sander by the insulated grips. Otherwise the tool may become “live” should it sand through its own power cord of that of another tool and cause a shock.
– Always wear safety goggles for eye protection, hearing protection, and a dust mask.
– Disconnect the sander cord plug from the power circuit before changing belts to prevent accidental start-ups.
– Avoid sanding of lead-based paint and other hazardous materials.
– Work in a well-ventilated area and provide for dust control. Direct particles away from face and body. Use a dust collection system wherever possible. Exposure to the dust may cause serious and permanent respiratory or other injury, including silicosis (a serious lung disease), cancer, and death.
– Avoid breathing the dust, and avoid prolonged contact with dust. Allowing dust to get into your mouth or eyes, or lay on your skin may promote absorption of harmful material.
– Always use properly fitting NIOSH/OSHA approved respiratory protection appropriate for the dust exposure, and wash exposed areas with soap and water.