The Skilsaw Cordless Worm Drive is the first Cordless Worm Drive circular saw to hit the market
While there are several "worm drive" cordless circular saws on the market, the Skilsaw Cordless Worm Drive Circular Saw is the first to actually use a worm drive. It's also Skilsaw's first cordless product, as the Pro brand is very different from Skil in terms of DIY.
advantage
- Best-in-class cutting power and performance
- excellent tracking
- Perfect notch accuracy at 45º and 90º
- perfect guard action
- very low shoe friction
- Excellent dust and swarf removal (no vacuum required)
- Includes a vacuum adapter
shortcoming
- Heaviest Rear Handle Set
- Compatible tools are currently limited
Skilsaw Cordless Worm Drive 48V TrueHVL Power Supply
Let's start with the power supply. The Skilsaw has a 48V battery and the kit comes with a 5.0Ah battery pack for a total of 240 watt hours. They refer to the battery system as "TrueHVL," for true high-voltage lithium batteries.
It's undeniably a big battery. 48 volts requires a 12 cell system with 24 cells in the battery pack. The backpack itself weighs 4.25 lbs.

That's probably not a big deal, though. When you look at the Skilsaw lineup, it's all about saws. Sidewinders are pretty much the smallest tools they make, followed by worm drives, chop saws, miter saws, and table saws (plus a few specialty saws).
Hopefully we'll see cordless versions of each of these tools. Weight is far less important than strength to get the job done in these classes. As long as the Skilsaw Cordless Worm Drive can glide efficiently through the material it's cutting, we can use a larger battery.
The Skilsaw's brushless motor spins its 7-1/4" blade at 5800 RPM. That's plenty of revs, and we have no doubt the 48V motor will confidently drive anything you send a wired worm drive to handle.
At 90º, you're looking at a depth of cut of 2-3/8", moving to 1-15/16" at 45º, and 1-11/16" at its full 53º bevel.
As a bare tool, it weighs just 11.09 lbs, while the batteries bring it to a full 15.34 lbs. Skilsaw's current corded 7-1/4" worm drive weighs 11.5-14.2 lbs, so the weight is a bit more, but not obnoxious. To save weight, the design team used magnesium for the guards, chassis and shell.

Their 16-5/16″ Super Sawsquatch weighs 27.3 lbs, just in case you were wondering.
price
There's no bare-bones option right now, but you can buy the Skilsaw cordless worm drive with battery and charger for $399. If you want to double the battery life, a dual-battery kit costs $599.
That's definitely at the high end of the market, but considering the company has been in the elite upper echelon of cordless circular saws, that's not surprising.
The result is out!

We tested the Skilsaw cordless worm drive in our best cordless rear handle circular saws article. It competes with other rear handlebars and Sidewinder styles, and it's clearly part of an elite group of cordless tools.
Performance
It can cut through two 3/4-inch layers of subfloor and has the top cutting power of any cordless chainsaw we tested.
Where it goes a step further is in removing dust and debris. After the vacuum was connected to its dust port, there was hardly anything left. Even when you're not using it, it removes debris better than other rear handle saws we've tested. Letting debris pass through the handle to the other side of the blade has proven to be very helpful in keeping the cutting line clean.
accuracy
If you like to keep your eyes on the blade while cutting, the Skilsaw is a good sight. It's not as wide open as we saw on Milwaukee's M18 Fuel rear grip, though. If you prefer to focus on shoe notches, you're in luck. With the Spyder frame blades installed, they lined up perfectly at 0º and 45º.
Skilsaw's tracking is also very accurate. Some saws we tested on the side tended to move 1/8" side to side, but the TrueHVL worm drive was also very accurate in our manual cuts.
move
We tested various crosscuts in 3/4" and 2x material as well as miter, miter and compound cuts. There are some models that have trouble with certain cuts. But in all of them, the Skilsaw cordless worm drive guard slides smoothly up and over the material.
The shoe also has very low friction compared to other cordless saws. The coating allows it to glide easily over the wood and helps you keep moving forward.
ergonomics
Being bare metal and with a 5.0Ah battery, Skilsaw's worm drive is heavier than similar products. This is not a big deal when cutting most materials due to the low friction of the sole and the excellent cutting ability. You'll notice it most when you're walking around a site with a saw, or if you have to make vertical or overhead cuts in installed material.
We really like the ergonomics of the handle, though. The angles are just right, and for those of us with sizable hands, there's some thickness to the side grip, which we appreciate.
the bottom line
Without a doubt, if you are looking for a high performance cordless circular saw, the Skilsaw cordless worm drive should be on your radar. It pinpoints the most important characteristics we look for in terms of performance, accuracy and movement. If you don't mind adding a little weight, the SPTH77M has everything you need to permanently replace your corded worm drive.
Skilsaw Cordless Worm Drive Circular Saw Specifications
- Model: Hacksaw SPTH 77 M-22
- Power: Skilsaw TrueHVT 48V battery
- Blade: 7-1/4″ (24T Diablo blade included)
- No-load speed: 5800 RPM
- Maximum cutting depth: 2-3/8″
- Weight: 11.09 lbs bare, 15.34 lbs with battery
- Warranty: 1 year
- Price: $399 (single battery kit), $599 (dual battery kit)