RYOBI R18AG-0 Cordless Angle Grinder, ONE+ 18V, 115 mm, 7500 rpm, Bare Tool - 5133001903

RYOBI R18AG-0 Cordless Angle Grinder, ONE+ 18V, Ø115 mm, 7,500 rpm, Bare Tool

The RYOBI R18AG-0 (article 5133001903) is a cordless angle grinder on the ONE+ 18 V platform, with a Ø115 mm disc and an M14 spindle. The "-0" suffix and the word SOLO mean the same thing: the tool ships without a battery and without a charger. The manufacturer's data for this article states "number of batteries included: 0" and "charger included: no". This version is for people who already own ONE+ 18 V batteries and do not want to pay for them twice.

What it is for

A 115 mm angle grinder is the most versatile machine in a workshop after the drill. It cuts rebar, profiles, sheet metal and bolts; it removes weld beads and rust; with a diamond disc it cuts tiles, porcelain stoneware and brick; with a wire cup it strips old paint. The cordless version has no cable to dangle into the cut, get severed by accident, or tie you to a socket - on a roof, up a ladder or on a site with no power, that is decisive.

115 mm and 7,500 rpm - what it means in practice

The manufacturer rates the no-load speed at 7,500 min^-1. On a Ø115 mm disc that works out to a rim speed of roughly 45 m/s - fast enough for the disc to cut the material rather than maul it. The safety consequence: every disc you fit must be marked for a speed no lower than 7,500 rpm. As a rule for the class, 115 mm discs on the market are marked for substantially higher speeds and meet the requirement, but that does not remove the check: read the marking on every disc, and especially on an old or non-standard one.

One caveat about the figure itself: the manufacturer states a fixed 7,500 min^-1 and the machine has no speed control. Some distributor listings nevertheless print the field as "0-7500" - that is how it appears in the its.co.uk table, while ahlsell.se gives 7500 in its technical data and "0-7500" in its article text. The discrepancy is on the distributors' side: the manufacturer's data wins, and you should not expect a speed dial.

The disc bore is 22 mm and the spindle thread is M14 - both standard for the class. That means the discs you already use on your corded 115 mm grinder will fit here too.

How much work you get per charge

RYOBI publishes a measured number of cuts in Ø13 mm steel on a single charge: 17 cuts with a 2.0 Ah battery, 21 with 2.5 Ah, 46 with 4.0 Ah and 57 with 5.0 Ah. The manufacturer itself describes the test in two different ways - uk.ryobitools.eu writes "57 cuts of 13mm threaded bar", while the specification label reads "Number of 13 mm steel pipes cut" and carries no value; that is why the material is given here neutrally as steel. Going from 2.0 Ah to 4.0 Ah does not double the work done, it nearly triples it. For more than the occasional cut, a 4.0 or 5.0 Ah battery is the sensible choice.

Three-position handle and tool-free guard

The side handle screws into three different positions - left, right and top. This is not a minor detail: cutting downwards and sanding a horizontal surface call for different grips, and left-handed users need the mirrored position. The three sockets let you set the machine up for the job instead of working in an awkward posture.

The wheel guard rotates and locks without tools. The same goes for the disc nut - for this model RYOBI specifies a "tool-less wheel guard and nut", which means changing a disc needs no spanner.

Two-stage switch and restart protection

The switch is two-stage and non-lockable: to start the machine, the slider is first released and only then pressed. Non-lockable means that the moment you let go, the machine stops - it cannot stay running if it gets away from you. The manufacturer describes the switch as one that prevents accidental start-up. Protection against unintended restart is also declared.

The ONE+ 18 V platform

RYOBI ONE+ is an 18 V platform on which one and the same battery powers the entire range - from drill drivers and grinders to garden machinery and lighting. Any ONE+ 18 V lithium-ion battery fits this grinder, including older packs from the platform.

The motor is not brushless

We say so explicitly, because it is a common misconception: the R18AG-0 has a brushed motor. its.co.uk explicitly lists "Brushless Motor: No", and RYOBI nowhere designates the model as Brushless. That is not a defect but positioning - the machine sits in the affordable class of the ONE+ platform and its price reflects that. There are two consequences: the brushes are a consumable, and battery consumption is somewhat higher than on a brushless grinder.

Technical specifications

What is in the box

• Cordless angle grinder RYOBI R18AG-0 - 1 pc.
• Wheel guard - 1 pc., adjusted without tools
• Side handle with three positions - 1 pc.
• NO battery - a ONE+ 18 V battery is purchased separately
• NO charger - a ONE+ charger is purchased separately
• NO carry case - the article is supplied in a cardboard box

A note on the disc and the spanner: some distributor data sheets (klium.nl and ahlsell.se) list both a grinding disc and a spanner among the contents, but RYOBI publishes no official contents list for 5133001903. Treat both as an illustration rather than a guaranteed part of the delivery - if you need a disc from day one, add one to your order. A spanner is not needed to change a disc on this model: the guard and the nut are operated without tools.

Working tips

• Check the marking on every disc: the permissible speed must be at least 7,500 rpm, and the size 115 mm with a 22 mm bore.
• Never remove the wheel guard. When cutting, turn it so that it sits between the disc and you - that is where the sparks go, and where the disc flies if it shatters.
• Let the disc reach full speed before it touches the material, and do not lean on it - pushing overheats the disc and drains the battery.
• Use the right disc: a thin cutting disc to cut, a thick grinding disc to remove material. Grinding with the side of a cutting disc is the most common cause of breakage.
• Goggles or a face shield are mandatory, gloves and ear defenders strongly recommended: 92 dB(A) sound power is above the threshold at which prolonged exposure damages hearing.

Questions and answers