Hangzhou Xinabo Intelligent Electromechanical Technology Co., Ltd manufactures intelligent pipe threading equipment and the cordless power tools that keep pipeline, fire-protection and construction crews working where a mains lead cannot reach. The XJ.908 21V Lithium-Ion High-Magnetic Brushless Angle Grinder — 100mm Disc, Cutting/Grinding/Polishing manufacturer is the 100mm model in our XJ.9 high-magnetic brushless platform, built for cutting, grinding and polishing metal, stone and welded joints on site.
The tool runs on a 21V DC lithium-ion pack with stepless speed control across the full no-load range, a 25mm maximum cutting depth and an anti-lock device that reduces speed when the disc meets resistance. It is the grinder we supply into renovation, auto body repair and light metal fabrication work, and into pipeline crews dressing welds and trimming profiles before threading and assembly.
- Rated voltage: 21V DC lithium-ion
- Motor: high-magnetic brushless, no carbon brush replacement
- Disc diameter: 100mm | Max cutting depth: 25mm
- No-load speed: 0–12,000 rpm, steplessly adjustable
- Functions: cutting, grinding, polishing | Safety: anti-lock, safety guard switch
The 100mm Brushless Grinder in Our Cordless Range
We build the XJ.9 grinder family in two disc sizes so a crew can match the tool to the cut rather than the other way round. The XJ.908 carries a 100mm disc and a 25mm cutting depth, which suits one-handed work in risers, plant rooms, ceiling voids and vehicle bodies where a 125mm body will not sit flat. Where the job needs deeper cuts and heavier stock removal, the XJ.918 21V high-magnetic brushless angle grinder takes a 125mm disc and reaches a 30mm cutting depth.
| Model |
Disc |
Max cutting depth |
Position in the range |
| XJ.908 |
100mm |
25mm |
Compact all-round cutting, grinding and polishing |
| XJ.918 |
125mm |
30mm |
Heavy-duty stock removal and deeper profile cuts |
XJ.908 Specifications and What Each Value Means on Site
The datasheet values below are the ones we quote and inspect against. They define the working envelope of the tool, not a best-case demonstration figure.
| Parameter |
XJ.908 value |
Practical meaning |
| Rated voltage |
21V DC |
Cordless operation on the 21V lithium-ion platform |
| Motor type |
High-magnetic brushless |
No brush wear items; sustained output under load |
| Disc diameter |
100mm |
Standard 4-inch consumables, low tool weight, tight access |
| No-load speed |
0–12,000 rpm, stepless |
Trigger-modulated speed for stainless, stone and polishing |
| Cutting depth |
25mm |
Covers threaded rod, angle, channel, tube and sheet up to that wall |
| Functions |
Cutting / grinding / polishing |
One body serves three operations with the right disc |
| Safety features |
Anti-lock, safety guard switch |
Speed drops on resistance to limit kickback; guard interlock on the switch |
| Standard accessories |
Side handle, guard, battery, charger, carry bag |
Tool is usable on delivery without separate accessory orders |
Application Fit: Metal, Stone and Auto Body Work
A 100mm disc turning at 12,000 rpm runs at roughly 63 m/s at the rim, comfortably inside the 80 m/s limit of standard bonded abrasives — but the disc itself must still carry a rating of at least 12,000 rpm. That single check governs which consumables we recommend for each task.
Renovation and strip-out
- Metal cutting: rebar, threaded rod, angle, conduit, sheet
- Stone and masonry grinding with the correct disc
- Weld polishing and seam dressing before inspection
Auto repair
- Body panel cutting and sectioning
- Paint and filler removal, metal polishing
- Low-speed starts for controlled contact on thin gauge
Metal fabrication
- Profile and section cutting to length
- Workpiece grinding and edge preparation
- Mould and die touch-up, surface blending
For stainless steel and other work-hardening alloys, we advise a dedicated stainless disc and a slower trigger setting to keep heat in the cut rather than in the parent metal. For aluminium and copper, a coarse-tooth disc or flap disc avoids loading. Thickness above 25mm falls outside the tool's cutting depth and belongs with the XJ.918 or a cold saw.
Speed Control, Anti-Kickback and Operator Safety
The anti-lock device monitors resistance at the disc and reduces speed when the tool binds, which limits the kickback that follows a pinched cut. The safety guard switch prevents the grinder from running with the guard removed, and the stepless trigger lets the operator bring the disc up to speed after contact rather than before it.
- Fit the side handle in the position that keeps the wrist neutral for the cut being made.
- Set the guard so the open sector faces away from the operator and the spark stream.
- Match disc type to material — cutting, grinding and flap discs are not interchangeable.
- Eye, hearing and respiratory protection apply to every operation; stone and coating removal generates fine dust.
Battery, Charger and the 21V Platform
The XJ.908 ships with a 21V lithium-ion battery and charger, so a crew can put it to work on delivery. The same 21V pack family runs across our cordless range, which means a site can standardise on one battery type across grinders, rotary hammers, impact wrenches and hammer drills.
Where a shift involves continuous cutting or weld dressing, the 20Ah/30Ah backpack lithium battery pack extends runtime and can power more than one 21V–60V tool. We size the battery count against the duty cycle you describe, not against a nominal figure.
Configuration and Accessory Scope
Disc set
Cutting, grinding and flap discs selected for the materials on the project, all rated for 12,000 rpm and above.
Power set
Battery and charger as standard; additional packs or the backpack pack quoted alongside for high-duty cycles.
Carry and storage
Portable carry bag included, with the guard and side handle stowed so the tool arrives complete.
Charger input configuration, battery quantity and the accessory set are fixed at order confirmation so the shipment matches the destination and the crew's working pattern. Related cordless tools such as the XJ.853 21V brushless circular saw can be consolidated onto the same battery platform in a single order.
Inspection, Acceptance and Documentation
Xinabo has operated from Hangzhou since 2010 and holds National High-Tech Enterprise status, with more than 30 patents across our machinery and tool development. Production runs through a 10,000 m² factory with dedicated assembly and inspection stages before packing.
- Function check on the safety guard switch and anti-lock response.
- No-load speed verification across the stepless trigger range.
- Battery and charger function test, with the pack checked for fit and release.
- Guard, side handle and disc mounting checked for correct seating.
- Visual and packaging inspection against the confirmed accessory list before dispatch.
Installation, Disc Changes and Maintenance
The grinder arrives assembled apart from the side handle and guard, which the operator fits before the first cut. Disc changes are made with the battery removed and the guard in place; the locknut is checked for tightness before every start-up. Because the motor is brushless, there are no carbon brushes to inspect or replace through the service life of the tool.
Routine care is limited to clearing dust from the ventilation path, checking the guard clamp and lead for damage, and storing the battery at a moderate state of charge away from direct heat. Consumable and wear parts — guard, side handle, charger, battery and carry bag — are supplied as spares so a tool does not leave service over a single item.
Information We Use to Configure Your Solution
Our proposal is built from the working point rather than a catalogue line. These are the details that let us confirm the model, accessory set and quantity in one pass:
- Material and section being cut, ground or polished, with maximum wall or thickness.
- Duty cycle per shift and the number of operators sharing the tool.
- Access conditions — riser, ceiling void, vehicle body or open fabrication bench.
- Disc types required and whether consumables should ship with the order.
- Battery quantity, charger input voltage and plug type for the destination.
- Order quantity, packing preference and delivery schedule.
- Any documentation or labelling required for site acceptance.
Frequently Asked Questions
What can the XJ.908 cut and grind?
With a 100mm disc and a 25mm maximum cutting depth, the XJ.908 handles threaded rod, rebar, angle, channel, conduit, tube and sheet steel, plus stone grinding and weld polishing with the appropriate disc. It also covers auto body panel cutting and paint or filler removal. Material thicker than 25mm needs the 125mm XJ.918 or a cold saw.
Is the speed adjustable, or is it single-speed?
Speed is steplessly adjustable from 0 to 12,000 rpm through the trigger. Operators can start slowly on thin gauge or stainless, then open to full no-load speed for cutting. The anti-lock device overrides the setting and reduces speed when the disc meets resistance.
What is included in the standard shipment?
Each XJ.908 ships with a side handle, guard, 21V lithium-ion battery, charger and portable carry bag. Discs are quoted separately according to the materials on the project, and additional batteries or the backpack pack can be added to the same order.
Does the 21V battery work with other Xinabo tools?
Yes. The 21V pack family is shared across our cordless range, including rotary hammers, impact wrenches, hammer drills and the circular saw, so a site can standardise on one battery type. The backpack pack extends that further and can power multiple 21V–60V tools during a shift.
How do you handle maintenance and spare parts?
The brushless motor removes the brush replacement interval entirely. Service attention is limited to dust clearance, guard and lead inspection, and battery care. Guards, side handles, chargers, batteries and carry bags are supplied as spares, and our technical team supports installers with training and product demonstrations on request.
English
Español
عربى
