Intro
For the home improver cutting metal fence posts to length, trimming a rusted bolt during a car repair, or slicing paving slabs for a garden path, a cordless angle grinder offers a compelling proposition: grab it from the shelf, fit a disc, and start cutting — no extension lead, no hunting for a socket, no cord tangling around the workpiece. Ryobi's ONE+ 18-volt system brings this convenience to their extensive range of over 200 compatible tools, meaning the same battery that powers your drill and circular saw also spins this grinder. For the DIYer who already owns Ryobi batteries, adding this bare-tool grinder and the included six-disc kit represents an accessible entry point into angle grinder work without the cost of a separate battery platform.
Generalities
The Ryobi R18AG-0 is an 18-volt cordless angle grinder taking 115 mm discs, operating at 7,500 RPM under no load. It is part of the Ryobi ONE+ system, sharing batteries with over 200 other Ryobi tools. This package bundles the bare-tool grinder with the RAK6AGD115 disc kit — one diamond disc for masonry and tile, and five metal cutting discs. The grinder weighs 2.5 kg without battery, and includes a three-position auxiliary handle, protective guard, spanner, and safety case.
This review examines the grinder's cutting performance, the convenience of the ONE+ battery system, the value of the bundled disc kit, and the home and garden applications where a cordless grinder makes the most sense.
Description
The grinder drives 115 mm discs at 7,500 RPM — lower than the 11,000 RPM typical of corded grinders, but adequate for the material thicknesses and cutting durations that a cordless DIY tool is designed for. The lower RPM also extends battery runtime, allowing more cuts per charge. The 115 mm disc size provides approximately 30 mm of cutting depth per pass. The spindle thread is M14, the standard for 115 mm discs, so replacements are widely available.
The bundled RAK6AGD115 disc kit is a practical inclusion. The single diamond disc handles masonry, tile, and stone — cutting paving slabs, bricks, and ceramic tiles for garden and bathroom projects. The five metal cutting discs cover the most common DIY metal cutting needs: trimming bolts, cutting metal brackets, shortening fence posts, and sectioning pipe. Having the discs included means you can start cutting immediately without a separate trip to buy consumables.
The grinder features a three-position auxiliary handle — left, right, and top — for comfortable control in different cutting and grinding orientations. The protective guard is adjustable and deflects sparks away from the operator. The spindle lock enables tool-free disc changes with the included spanner. At 2.5 kg without battery (approximately 3.0 kg with a standard 2.0 Ah battery), the grinder is manageable for two-handed cutting and one-handed light grinding.
As a bare tool, the grinder does not include a battery or charger — it is designed for users who already own Ryobi 18V ONE+ batteries. Runtime will vary with battery capacity: a 2.0 Ah battery provides enough power for dozens of quick cuts in thin metal, while a 5.0 Ah battery extends runtime for longer sessions. The tool is backed by Ryobi's 2-year warranty, extendable to 3 years with product registration within 30 days of purchase.
At time of writing there is only one customer review (rated 5.0 stars), providing very limited real-world feedback. The grinder is positioned in Ryobi's home-and-garden range — it is designed for intermittent DIY use rather than daily professional work. For the homeowner who already owns Ryobi ONE+ batteries and needs a grinder for occasional cutting and grinding tasks, this package offers a complete start-up solution with discs included.
Pros and cons
Pros
- Part of the Ryobi ONE+ ecosystem — shares batteries with over 200 tools, making this an affordable addition for anyone already invested in the Ryobi 18V platform
- Bundled disc kit with one diamond masonry disc and five metal cutting discs means you can start cutting immediately — no separate disc purchase required
- Cordless freedom with no extension leads — ideal for garden projects, remote outdoor work, and quick cuts anywhere around the property
- Three-position auxiliary handle and adjustable guard provide comfortable, safe operation in different cutting and grinding orientations
- Standard 115 mm M14 disc fitting — replacement discs in every type and material are widely available and affordable
- Includes safety case for protected storage and transport — keeps the grinder, discs, and spanner organised and protected between uses
Cons
- Only one customer review available — extremely limited real-world feedback on performance, battery runtime, and long-term durability
- 7,500 RPM is slower than corded grinders (typically 11,000 RPM) — cutting speed is reduced in exchange for extended battery runtime
- Bare tool — battery and charger not included, adding significant cost if you are not already invested in the Ryobi ONE+ battery platform
- Battery runtime limits continuous use — this is a DIY tool for intermittent cutting and grinding, not sustained professional operation
- At 2.5 kg without battery (approximately 3.0 kg ready to use), the grinder is heavier than some competing cordless grinders in the 115 mm class
Use cases
This cordless angle grinder with disc kit is designed for home improvers and DIY enthusiasts already using the Ryobi ONE+ battery system who need a convenient, grab-and-go tool for occasional metal cutting, masonry cutting, and light grinding around the home and garden.
Home Metal Cutting and DIY
Cutting metal fence posts, trimming bolts and threaded rod, sectioning metal pipe, modifying brackets, and general light metalwork around the home. The included five metal cutting discs handle these common DIY tasks, and the cordless freedom means you can work in the garden, the garage, or anywhere without power access.
Masonry and Garden Projects
Cutting paving slabs, bricks, and concrete blocks for garden paths, patios, retaining walls, and boundary walls using the included diamond disc. The cordless operation is particularly useful for outdoor projects where running extension leads across a garden is inconvenient or unsafe.
Automotive DIY and Repairs
Cutting off rusted exhaust clamps, trimming bolts, freeing seized fasteners, and light bodywork metal cutting during car maintenance and repairs. The cordless design reaches into engine bays and under vehicles without managing power leads in cramped, dirty spaces.
Ryobi ONE+ System Expansion
For homeowners who already own Ryobi ONE+ batteries from a drill, impact driver, or garden tool set, this bare-tool grinder adds cutting and grinding capability at minimum cost. The same batteries power the grinder with no new charger or battery platform to buy.
Occasional Grinding and Deburring
Light grinding of rough edges after cutting, removing rust spots from garden tools and metal furniture, and deburring cut ends of pipe and rod. The grinder handles these short-duration tasks adequately — it is not designed for sustained heavy grinding of welds or large surface areas.