DeWALT DCS391N Review: The Best Entry-Level 18V Cordless Circular Saw?
DeWALT DCS391N Review. If you’ve been relying on a corded circular saw for years, the freedom of switching to a cordless system is a game-changer. I recently treated myself to the DeWALT DCS391N 18V XR Li-Ion Circular Saw after my old corded unit finally gave up the ghost.
In this guide, I’m unboxing the DCS391N, looking at the build quality, and showing you exactly how to set it up for your next DIY project.
Watch the Unboxing & Setup
Why the DeWALT DCS391N?
I’m a big fan of the DeWALT eco-system because you can buy these units as “Bare Bones” (the tool only). If you already have DeWALT batteries from other tools, like a drill or impact driver, they are completely interchangeable.
Key Specs at a Glance:
- Voltage: 18V XR Li-Ion.
- Blade Diameter: 165mm (20mm bore—very common and cheap to replace).
- Max Cutting Depth: 55mm at 90° (perfect for 2-inch timber).
- Bevel Capacity: Up to 50°.
- Price Point: I paid roughly £114 (inc. VAT), making it a fantastic entry-level pro saw.
Build Quality & First Impressions
Straight out of the box, the DCS391N feels like a “Built By Pete” tool—sturdy and reliable.
- Base Plate: It features a forged aluminium base which is far superior to the stamped steel bases found on cheaper DIY brands.
- Grip: The rubberized twin grip feels secure in the hand, which is vital for safety when making long cuts .
- Safety Features: It includes an electronic brake that stops the blade almost instantly the moment you release the trigger .
How to Install the Blade (Step-by-Step)
Changing a blade on a circular saw can be fiddly, but DeWALT has made this fairly straightforward. Remember: Remove the battery before doing this!
- Lock the Blade: Push the blade lock button located behind the handle to stop the spindle from spinning.
- Unscrew the Bolt: Use the provided Allen key (stored on the back of the tool) to turn the bolt anticlockwise to unlock it.
- Check the Direction: Slide the 165mm blade into the guard. Ensure the directional arrow on the blade matches the arrow on the saw.
- Tighten (Opposite Thread): Replace the collar and nut. Note that this is an opposite threaded screw, so you turn it anticlockwise to tighten. It doesn’t need to be super tight as it self-tightens during use.
Adjusting Depth and Angle
For precise DIY work, you need to be able to adjust on the fly:
- Depth Adjustment: A simple tab on the back allows you to slide the base up and down. At a 50° angle, your max depth is around 42mm.
- Bevel Cuts: The front knob allows you to tilt the saw up to 50°. There is a clear scale to help you set the exact angle for rafters or decorative cuts.
Pros and Cons: The DeWALT DCS391N at a Glance
Before you buy, here is the breakdown of why this saw is a staple in my workshop—and where it falls slightly short.
| Pros | Cons |
| Value for Money: At around £114, it’s a high-quality entry point into professional tools. | Bare Unit Only: Does not include a battery or charger (you’ll need existing DeWALT 18V XR kit). |
| Safety First: The electronic brake stops the blade instantly, reducing the risk of accidents. | No Carry Case: Ships in a cardboard box, so you’ll need to buy a T-STAK case separately if you want to protect it. |
| Forged Aluminium Base: Much more durable and accurate than the thin stamped steel bases on cheap DIY saws. | Brushed Motor: While powerful, it’s not as efficient as the more expensive “Brushless” versions. |
| Easy Maintenance: Uses standard 165mm blades with a 20mm bore, available almost everywhere. | Dust Extraction: Requires an additional adapter if you want to hook it up to a vacuum. |
165mm Blade Buyer’s Guide: Choosing the Right Teeth
The DCS391N uses a 165mm diameter blade with a 20mm bore. While the 24T blade that comes in the box is great for framing, it’s not the right choice for every task. Use this table to find the best blade for your specific project:
| Task | Tooth Count (T) | Finish Quality | Best For… | Recommended Blade |
| Ripping | 12T – 16T | Coarse | Fast, long cuts along the wood grain. | Trend Craft Pro Ripping |
| General Purpose | 24T | Medium | Framing, structural timber, and 2x4s. | DeWALT Elite Framing |
| Fine Finish | 40T – 42T | Clean | Skirting, architrave, and furniture. | DeWALT Extreme 2nd Fix |
| Extra Fine | 48T – 60T | Smooth | MDF, plywood, and laminate sheet. | Trend Craft Fine Trim |
| Ultra Fine | 80T+ | Perfect | Plastics, thin veneers, and paneling. | Saxton Ultra Fine |
Pro-Tip: Go “Thin Kerf” for Cordless
When buying spare blades for the DCS391N, always look for “Thin Kerf” options (usually around 1.5mm to 1.7mm wide). Because the blade is thinner, it removes less wood and creates less friction. This means:
- Longer Battery Life: Your 18V battery will last up to 30% longer per charge.
- Less Motor Strain: The saw doesn’t have to work as hard, which extends the life of the tool.
DeWALT DCS391N Review – The Final Verdict
If you are already invested in the DeWALT 18V battery system, this saw is an absolute “no-brainer” for general DIY and construction tasks like the Smart Shed build. It’s rugged, simple to adjust, and provides that cordless freedom that makes a weekend project much more enjoyable.
Is it Worth It?
If you are already in the DeWALT 18V system, the DCS391N is a no-brainer. It’s well-constructed with a tough plastic motor cover and a forged aluminium base that can take a beating on a job site or in a workshop. While the newer DCS565 is brushless, the DCS391N remains a favorite for DIYers because it’s often significantly cheaper while still delivering plenty of power for 2-inch timber.
While it doesn’t come with a box or battery at this price point, its reliability and ease of use make it a staple tool for any serious DIYer.
DeWalt DCS391N Circular Saw FAQ
What is the maximum cutting depth of the DeWalt DCS391N?
The saw offers a maximum depth of cut of 55mm when set at a 90° angle. When adjusted for a 45° bevel cut, the maximum depth is 42mm.
Is the DeWalt DCS391N a brushless model?
No, the DCS391N features a powerful PM58 fan-cooled motor with replaceable brushes. While it isn’t brushless, it is highly regarded for its reliability and ease of maintenance.
What size blade does the DCS391N use?
It uses a 165mm (6.5 inch) blade with a 20mm bore. It typically comes with an ultra-thin kerf, 24-tooth carbide-tipped blade designed for efficient run time and smooth finishes.
Does this saw include a battery and charger?
The “N” in DCS391N stands for “Naked,” meaning it is sold as a bare unit. You will need to provide your own DeWalt 18V XR Li-Ion batteries and a compatible charger.
What are the key safety features of this saw?
The DCS391N is equipped with an electronic motor brake that stops the blade quickly once the trigger is released, an intelligent variable speed trigger, and a lock-off switch to prevent accidental starts.
Can I adjust the bevel angle on the DCS391N?
Yes, the saw features a keyless bevel angle adjustment. It allows for bevel cuts up to 50°, with an easy-to-read scale for precision.
Is the baseplate durable?
The saw features a cast magnesium baseplate. Magnesium is chosen because it is significantly lighter than steel but more durable and rigid than aluminum, ensuring the tool stays accurate over time.
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