The oscillating “multi-tool” (OMT) plunges through plywood, quickly cuts holes in drywall, shears-off metal pipes, trims moldings, grinds-out grout, sands surfaces, and much more. Here’s how to buy the best oscillating multi-tool.
The oscillating multi-tool (OMT) is a tool that every Mr. Fixit will love. It saws, scrapes, sands, polishes and more. The magic of this tool is that it powers blades, scrapers, sanders, and cutting tools to handle a wide variety of home improvement tasks. And, best of all, it goes places where other tools can’t go.
If you want to remove crusty old adhesive from a concrete slab, just clip-on a scraper blade. For grinding the grout from between ceramic tiles or doing other masonry work, a carbide- or diamond-edged blade is the answer. You can cut metal strips, nails, bolts and pipes with a bi-metal blade. Or you can use wood-cutting blades to make specialized saw cuts where other saw blades can’t go.
What Is An Oscillating Multi-Tool?
The OMT is a relative newcomer to the world of power tools. Until about 10 years ago, a very similar tool removed casts in doctor’s offices. Tool manufacturers recognized some of that tool’s unique capabilities and began producing consumer models for home improvement tasks. Since then, the oscillating multi-tool has become the tool of choice for many home improvement jobs.
As its name suggests, the oscillating multi-tool’s cutting motion is different than that of a conventional power saw. Unlike a power circular saw, jigsaw, or reciprocating saw, its blade doesn’t saw back and forth or cut while spinning in a circle. Instead, it has a flat metal blade that oscillates side to side about 20,000 times per minute.
As a result, the oscillating tool doesn’t kick-back or grab during cutting the way another saw might. And, because of its small size and the location and offset shape of a typical blade, it can make precise curved or straight cuts in very tight spots, such as in corners or flat against the floor.
Blades and Accessories
Many types and shapes of blades and accessories are made for these tools, as you can see in the Bosch selection shown here. These include various wood-cutting and metal-cutting blades, triangular-shaped sanding pads that hold adhesive-backed sandpaper of varying grits, carbide- and diamond-edged blades for cutting masonry, and more.
When you buy an oscillating tool, most manufacturers include a few basic blades and accessories, as well as a cloth tool bag or hard case for holding the tool and its accoutrement.
Because blades, grinders, and cutters wear out, the ability to easily and affordably buy replacements is an important consideration. Several major manufacturers use either a standardized mounting system or adaptors that allow mounting other brands of blades and accessories. In addition, after-market blades and accessories are made by a variety of tool makers.
Note that, although some of the saw blades have a semi-circular shape, they don’t spin. This shape simply allows them to make oscillating cuts from a variety of directions.
Corded or Cordless?
Both corded and battery-operated oscillating tools are sold. Battery-operated cordless models take advantage of new lithium batteries for power and extended life and, of course, can be used anywhere. But, after several years of use, cordless tool batteries cease to take a charge and must be replaced. Replacement batteries can be expensive (from a low of about $20 up to $75 or more).
Corded models are generally more powerful and—as long as they’re plugged-in—never run out of juice. An oscillating tool is typically used where it isn’t difficult to plug it into an extension cord. In fact, some models have very long (up to 20-foot) cords of their own. For this reason, a corded model makes the most sense unless you plan to use the tool where an electrical outlet isn’t reachable.