Buehler AutoMet 250 Semi‑Automatic Grinder‑Polisher
The AutoMet 250 semi‑automatic grinder‑polisher combines a robust 1 hp (750 W) platen drive, programmable platen speeds from 10–500 rpm, and a semi‑automatic power head to deliver consistent grinding and polishing for routine metallography and quality‑control labs. Its membrane control panel with digital readouts makes it easy to set and repeat key parameters, while the D‑style bowl, retractable water hose, 360° bowl rinse and disposable liners simplify daily cleaning and changeover between abrasives or cloths.
Supporting both single‑force and central‑force modes, AutoMet 250 handles standard 1 in, 1.25 in, 1.5 in, 25 mm, 30 mm and 40 mm specimens, making it suitable for a wide range of steels, super‑alloys, coatings and electronics. When combined with CarbiMet grinding paper, MetaDi diamond suspension and Buehler polishing cloths, plus optional Burst automatic dispensing modules, the system delivers repeatable surface finishes and reduced operator variability in medium‑to‑high‑volume sample preparation environments
Technical Specification of Buehler AutoMet 250
AutoMet 250 Base
| Machine Power | 100–240 VAC, 50/60 Hz, 1 phase. |
| Motor Power | 1 hp [750 W] base motor. |
| Platen Diameter | 8 in [203 mm], 10 in [254 mm]. |
| Platen Speed | 10–500 rpm in 10 rpm increments. |
| Wheel Direction | Clockwise or counter‑clockwise. |
| Water Supply Hose | 0.25 in [6 mm] OD tube. |
| Water Supply Pressure | 40–100 psi [2.7–6.9 bar]. |
| Base Power Usage | 1.1 kW, 9.6 / 4.8 A @ 115 / 230 VAC. |
| Base & Head Power Usage | 1.73 kW, 15 / 7.5 A @ 115 / 230 VAC. |
| Control Panel | Membrane keypad with three 3‑digit LED displays and 14 status LEDs; metric or imperial units. |
| Base Sound Rating | 59.5 dB @ 100 rpm (no load, 0.5 m distance). |
| Base & Head Sound Rating | 61.5 dB @ 100 / 30 rpm. |
| Weight | 170 lb [77 kg]. |
| Compliance | CE; EC applicable directives. |
AutoMet 250 Power Head
| Head Motor Power | 0.156 hp [116 W] power head. |
| Head Speed | 30–60 rpm in 10 rpm increments. |
| Central Specimen Force | 5–60 lb [20–260 N]. |
| Single Specimen Force | 1–10 lb [5–45 N]. |
| Central Force Capacity | 1 in, 1.25 in, 1.5 in, 25 mm, 30 mm, 40 mm and large or irregular specimens. |
| Single Force Capacity | 1 in, 1.25 in, 1.5 in, 25 mm, 30 mm, 40 mm specimens. |
| Air Supply Hose | 0.25 in [6 mm] OD tube. |
| Air Supply Pressure | 35 psi [2.4 bar]. |
| Head Power Usage | 630 W, 5.5 / 2.7 A @ 115 / 230 VAC. |
| Head Weight | 70 lb [32 kg]. |
| Compliance | CE; EC applicable directives. |
Key Features & Benefits of Buehler AutoMet 250
Key Features
- Semi-Automatic Operation: Power head with single-force and central-force modes for flexible grinding and polishing cycles.
- Membrane Control Panel: Simple push‑button controls with digital displays for platen speed, time and head parameters.
- High-Performance Drive: 1 hp base motor supporting 10–500 rpm platen speeds on 8 or 10 in platens for medium to high volume work.
- Quick Clean Design: D‑style bowl, retractable water hose, 360° bowl rinse and disposable liners for fast clean‑up.
- Burst Compatibility: Supports up to 5 Burst units to automatically dispense diamond suspension and lubricant during polishing.
- Versatile Specimen Handling: Accepts 1–1.5 in and 25–40 mm specimens in both single and central-force holders, including irregular samples.
User Benefits
- Higher Throughput: Semi‑automatic cycles and Burst dispensing reduce operator involvement and increase sample volume per shift.
- Consistent Results: Digital control of speed, time and force delivers repeatable surface quality across operators and days.
- Reduced Consumable Use: Controlled diamond and lubricant dosing helps minimize waste and improves cost efficiency.
- Lower Maintenance Time: Integrated rinse and disposable liners make it quick to change abrasives or cloths between steps.
- Ready for Many Materials: Suitable for steels, superalloys, coatings, ceramics and electronics when used with appropriate Buehler consumables.
Ordering Information
| AutoMet® 250 Semi-Automatic Grinder-Polisher | |
|---|---|
| Part Number | Voltage |
| 49-72xx* | 100–240 VAC, 50/60 Hz, 1 phase |
Consumables and Accessories
Frequently Asked Questions
AutoMet 250 is intended for routine metallographic grinding and polishing of mounted specimens in medium to high volume labs, especially where 8 or 10 in platens and semi‑automatic control are sufficient. [web:185][web:190]
The power head supports both central and single‑force holders for 1 in, 1.25 in, 1.5 in, 25 mm, 30 mm and 40 mm mounts, as well as larger or irregular specimens in central‑force mode, up to about 40 mm diameter. [web:185][web:193]
AutoMet 250 requires 100–240 VAC, 50/60 Hz single‑phase power, a water supply at 40–100 psi via 0.25 in OD tubing, and compressed air at about 35 psi for the power head. A drain connection for the bowl rinse is also needed. [web:185][web:193]
The grinder‑polisher includes a D‑style bowl, integrated 360° bowl rinse, retractable water hose and disposable bowl liner so abrasive residue can be flushed and liners replaced quickly between steps. [web:185][web:188][web:190]
Recommended consumables include CarbiMet™ silicon carbide paper for grinding, MetaDi™ diamond suspension and lubricant for polishing, Buehler polishing cloths, and optional Burst automatic dispensing units for controlled slurry delivery. [web:185][web:188][web:181]
AutoMet 250 Pro adds a touchscreen, multi‑step method storage and Z‑axis depth grinding, while AutoMet 300 Pro increases platen size to 12 in for larger samples and higher throughput, making them better choices for fully programmable workflows or larger parts. [web:186][web:190][web:193]
