Tool basics – cordless circular saws
New, and much improved, cordless circular saws are versatile and powerful enough to make the cut
When the first cordless tools appeared in the 1980s, they were all limited by the same thing: wimpy batteries. That’s why it’s been interesting to watch new tools emerge in cordless form because batteries and chargers have improved. With each incremental rise in battery power and longevity, technical possibilities become realities. And of these, I find the development of cordless circular saws the most startling.
It’s now possible to frame an entire house efficiently using only the cutting power of a cordless saw and a pair of batteries swapped back and forth in the charger. Cordless saws still aren’t quite as gutsy as corded models, but manufacturers tell me that their largest cordless saws are designed to provide 80 per cent of the output of corded models. And that’s enough to handle the full range of cutting jobs without excuses. Even 45° bevels are possible with the large-blade models. The question isn’t whether these saws are able to cut serious lumber, but whether cordless suits your style of work. Is cord-free cutting worth a higher purchase price, plus the occasional and not-so-insignificant expense of replacing batteries?
Many of these saws are available as kits with other cordless tools, often drills. If you need the extras, these kits can be a better buy than the saw alone.
Before running a range of cordless saws through their paces on construction lumber (with about 20 per cent moisture content), I took a close look at each model in my workshop. After operating guards and triggers, installing blades and charging batteries, each saw was used to rip and crosscut 2 x 8 stock to assess their stamina, ease of use, control layout and general field performance. The results boosted my confidence in this tool category more than I thought possible.
Big on Blades
One reason early cordless saws couldn’t handle all cutting tasks was because of their small-diameter blades-some only 4 3/8″ across. But as power increased, larger blades became possible. You’ll now find 6 1/2″ blades on most 18-volt cordless saws, and 7 1/4″ blades on some 24-volt machines. To maximize cutting power, cordless saws use thin-kerf blades with low-friction coatings. These work just as well as full-thickness blades in my experience.
When choosing a cordless saw, consider depth of cut and how it relates to blade size. The smallest machines currently spin 5 1/2″ blades, which is just barely enough to square-cut standard 2-by framing lumber. Consider models with a 6 1/2″ or 7 1/4″ blade if you’re planning to cut thicker rough lumber, or regular framing stock at bevelled angles.