Every So Often a Sudden and Significant Advance Happens in The World of Tools

Every so often a sudden and significant advance happens in the world of tools, and now is one of those times. It’s called brushless motor technology, and it promises to instantly boost the performance of cordless tools across the board. All tool manufacturers are scrambling to bring brushless tools to market, and though most cordless tools on store shelves aren’t brushless yet, the new technology is worth looking for. To understand why, you need to understand what brushless is all about. Most power-tool motors include small, spring-loaded blocks of carbon hidden inside. These blocks are called brushes and they press against the revolving part of the motor, delivering electricity to it, while helping to create a revolving electrical field. It’s this revolving field inside the motor that makes it spin, and brushes have been an integral part of making this happen for more than a century. But as useful as they’ve been, brushes pose two major limitations: Since brushes are designed to rub against revolving internal motor parts, they wear out in time. That’s just the way it is, and if brushes aren’t replaced in time, any motor will be ruined with continued use. Another problem with brushes is the energy they waste. Rubbing means friction and sparking, and this translates to less work done on each battery charge, all else being equal. Brushless tools sidestep both the problem of wear and the problem of friction, and they do this with a much simpler design than older, brush-style motors. Compare the two kinds of tools side by side and you can easily see the difference, even if you don’t know anything about motors. Instead of the mechanical system of brushes, springs and other parts that make electric motors spin, brushless tools use electronic circuitry to accomplish the same thing with far fewer moving parts. The results are some pretty tall claims from manufacturers for longer tool life and more work accomplished per charge. Brushless tool motors are supposed to last at least 1,000 per cent longer than brush-style motors before wearing out, and they’re supposed to deliver 50 per cent more work from a given battery pack before charging is necessary. But claims are easy to make, and that’s why I decided to check out the reality myself. To test brushless tool speed and endurance, I fitted an 18-volt Milwaukee FUEL 2604 brushless drill with the same kind of 9/16-inch drill bit I put into two new comparable brush-style drills: the 20-volt DeWALT DCD989 and the 18-volt Makita BHP454. All three tools had fully charged 3.0 amp-hour batteries at the beginning of each test run. I measured how many 10-inch-deep holes I could drill in the end of hard maple logs on a single charge, and how long it took to drill these holes. I repeated this test several times, averaging the production and speed numbers for accuracy. Bottom line: The Milwaukee brushless FUEL drilled ran 40 per cent longer than the best competing brush drills on the same size battery, and 22 per cent faster than the next-best model. Source: yourhome.ca