Cordless drill/drivers have come a long way since the first one I purchased more than 20 years ago. It's interesting, though, that some have come full circle and ended up about the same size as those small, early tools, but with much better performance.
Compact and subcompact cordless tools are fast-growing categories in part because of lightweight lithium-ion (LI) batteries. Even after tool companies took many LI tools to higher voltages for higher-capacity performance, demand for lighter tools that are "strong enough" remained the standard for some categories. The market proved that most users don't need a 36-volt drill; they'd rather have an 18-volt model of familiar size and capability but with the weight benefit of LI. Compact drill/drivers go a step lighter with slightly smaller bodies and half-sized batteries; subcompacts are smaller yet.
All the compact drill/drivers we tested are similar, with two speed ranges, multiple clutch settings, and 1/2-inch chucks. All come in a kit with a case, charger, and two half-sized, reduced amp-hour batteries. And all fit full-size batteries for longer runtimes but with some extra weight, except for the lone 14.4-volt tool, which comes with lightweight, full-size batteries.
There are two varieties of subcompacts: drivers with 1/4-inch hex bit holders, and drill/drivers with 3/8-inch chucks. All but one have an adjustable clutch, and some have two speed ranges for versatility. These tools also come with cases, chargers, and two batteries. And even though some brands label their batteries as 10.8 volts and others as 12 volts, all the batteries are made of three similar LI cells and comprise the same voltage class.
The benefits of smaller tools became clear after I spent a day using them on the job. I had been happy enough using my heavy, full-sized nicad drill/driver for most of my installation work until I used the compacts in its place. For general jobsite uses, such as screwing cabinets to walls, I found they had plenty of power, even enough for driving 3/8-inch lag bolts.
The utility of the subcompacts was more of an eye opener. After using them for installing drawer slides inside a 12-inch-wide base cabinet, I wondered how I had gotten along without one, or at least why I had. They are just the right size for all sorts of cabinet assembly in the shop and for hardware attachments on the job. I found them all powerful enough to drill 5/16-inch holes, but I wouldn't have one as the only driver on my jobs.
The subcompacts drew a lot of attention from my subs; everyone wondered if these little drivers were at home on a pro's jobsite. The electrician used them to change devices in several rooms, and the HVAC guy used them for sheet-metal screws while installing a furnace and ducting. The subcompacts got such a workout that they soon developed the well-worn look of favorite old tools.
In the shop, we performed side-by-side tests to determine relative power and comparative battery runtime. The speed of completing the same task roughly defines a tool's power, especially if the rpms are similar. So I timed and averaged a dozen trials of driving 3-inch screws into a softwood 4x4 with each tool in low gear.
I also tested the amount of work each tool could perform on one battery charge by driving 3-inch screws until each battery gave out. For the compacts, I drove the first 35 screws into super-dense ipe wood, and the rest into another 4x4. For the subcompacts, only the first 20 went into the hardwood. This flat-out endurance test was not only grueling for the tools, but for us as well. We drove more than 1,500 screws for our data.
The shop tests provided for an interesting comparison of the tools, but I found my jobsite experience to be more telling overall. You can grab a charged battery if your tool doesn't run the longest, but you can't make an awkward-feeling tool comfortable. Most every tool proved strong enough for its intended use, and if I need stronger or faster than a compact drill/driver, I'll go corded anyway.
Of the eight compacts, the Milwaukee came out on top with smooth performance, ergonomics second to none, and all the best features. Makita and Panasonic share second place with great performance and feel. These lightweight tools are among the most comfortable to use. The powerful Bosch took third, and the rest in order were Craftsman, Hitachi, Porter-Cable, and Ryobi.
Among the nine subcompacts, I generally prefer the smaller bit-holder driver models for their easier access to tight spots. The best overall is the Milwaukee, with top comfort and features. Makita, Bosch, and Hitachi follow in this class.
The more versatile subcompact drill/drivers with a chuck might serve as the only driver for jobs with light-duty demands. For this class, the Bosch is best, followed by Makita, Ridgid, Craftsman, and Ryobi.
David Getts is an architectural wood-worker and remodeler in Seattle.