Balance and Comfort: How well a sander’s weight is distributed and balanced affects how it handles. Handle size and placement, as well as trigger location and functionality, determine comfort and handling friendliness.
Power and Speed: Most of us lean into the sander now and again. Pressing down takes power, and not all belt sanders have the same amount on tap. The speed of the belt also affects how quickly the tool sands wood: Faster belt speeds translate into rapid stock removal. Slower belt speeds are useful for delicate sanding jobs.
Platen Size: In addition to a sander’s power and belt speed, the amount of abrasive belt in full contact with the work surface affects sanding efficiency. The more length a platen has, the more the grit particles are abrading wood. Having a platen that’s a bit wider than the sanding belt keeps the abrasive in good contact with the work.
Belt Change and Tracking: Any sander is only as good as its abrasive belt, so keeping fresh abrasive particles working for your 3×21 means changing the belt. This can be effortless or tedious, depending on the design and construction of the tool’s belt tension release mechanism. Once a new belt is in place, an effective and easy-to-use belt tracking knob gets you back to work quickly.
Good Dust Collection: All belt sanders make a ton of fine wood dust. The best way to keep your shop clear of dust is to use the tool’s built-in dust port connected to a shop vacuum. The included dust bag is better than nothing, if you must work without a vacuum.
Body Insulation and Cord Length: A tool with a double-insulated body offers just a touch more protection for the user when working in wet conditions or when the cord or wiring short out. Non-insulated models provide this protection by having a ground wire, so it’s essential that you plug such tools into grounded (and preferably ground-fault protected) outlets. Because of the amount of tool motion that’s often required when sanding large panels and cabinets, long power cords are preferred.