SJG-900 / 900A Patternless lens edger that edges glass lenses, plus a PC version
A patternless edging system in two units for shops that still fit mineral glass: an optical scanner that captures the frame shape and centers the lens in one step, and an automatic edger that shapes and polishes. No pattern is needed. The SJG-900 edges glass as well as resin and polycarbonate; the SJG-900A is for resin, high-index and PC only, with two selectable bevel positions and an electronic level. On both, you enter PD and fitting height directly on the scanner.
Delivery, packing and documents
What the SJG-900 and 900A do
Glass version or PC version
The SJG-900 shapes glass, resin and polycarbonate lenses to the traced outline; the SJG-900A covers resin, high-index and PC.
Scan and center in one step
Optical scanning and center positioning are built into one unit, and the frame shape is captured in 0.5 seconds.
PD and fitting height entry
Enter pupillary distance and fitting height directly on the scanner, and the lens is aligned to its axis line automatically.
Corrected centering image
Live imaging on the 7-inch 800 × 600 touch screen, with the lens’s power, prism and parallax removed from the view.
Polished bevel and flat edges
Polishes both bevelled and flat edges, with several grinding pressures to choose from for different lenses.
Auto calibration and data link
Calibrates itself and links to the scanner for data, with an 8-inch capacitive touch screen on the edger.
SJG-900 or SJG-900A
Same machine body, scanner and specifications. The difference is the lens materials and how the bevel is set.
| SJG-900 | SJG-900A | |
|---|---|---|
| Lens materials | Glass, resin, polycarbonate | Resin, high-index, polycarbonate (no glass) |
| Bevel | One fixed bevel position; polished bevel and flat | Two selectable bevel positions, fixed for thin and thick lenses; polished bevel and flat |
| Electronic level | — | Yes |
| Edging | 2D, scanner-guided, no probe | 2D, scanner-guided, no probe |
| Choose it if | You edge glass lenses, even occasionally | You edge only resin, high-index and PC |
Need a custom bevel position, a probe that measures the lens in 3D, or a mini bevel for thin metal rims? See the SJG-910A.
A closer look at the SJG-900
Grinding chamber
The lens clamp shaft sits under a hinged clear splash guard, with water nozzles on each side to cool the lens while it is edged.
Wheel stack
The Ø90 mm wheels run behind the lens shaft. The wheel configuration for your mix of glass, resin and PC is confirmed on the quotation.
Scanner screen
The 7-inch screen shows the traced shape with its width and height, a keypad for PD and fitting height, and right/left lens switching.
SJG-900 / 900A in figures
Published specifications. Anything not listed here is confirmed in writing on your quotation, never estimated.
The scanner and the edger are connected for data. One scanner connects to one edger as standard. Both versions share these figures except lens materials and bevel settings.
Edger
- Lens materials
- SJG-900: glass, resin, polycarbonate · SJG-900A: resin, high-index, polycarbonate (no glass)
- Lens size range
- 25–80 mm
- Grinding wheel
- Ø90 mm
- Clamping pressure
- 3 levels
- Edge profiles
- Bevel, polished bevel, polished flat
- Screen
- 8" capacitive touch screen
- Voltage
- AC 220 V / 110 V, 50/60 Hz
- Power
- 550 W
- Dimensions
- 650 × 540 × 450 mm
- Weight
- 65 kg
Scanner
- Shape capture
- 0.5 s
- Functions
- Optical scanning and centering; PD and fitting height entry
- Screen
- 7" capacitive touch screen, 800 × 600
- Screen tilt
- 20°–100°
- Connectable edgers
- 1
- Voltage
- AC 220 V / 110 V, 50/60 Hz
- Power
- 60 W
- Dimensions
- 230 × 370 × 200 mm
- Weight
- 5 kg
Edging glass lenses without patterns
Why glass still matters
Mineral glass is still ordered in many markets: it resists scratches, stays optically stable and costs little in common powers. It also behaves differently at the wheel. Glass is harder and more brittle than plastic, so it needs a wheel made for it and steady water cooling, or the edge chips.
Many patternless edgers are now built around polycarbonate and high-index lenses and leave glass out. The SJG-900 keeps glass in the list next to resin and PC, so a shop with a mixed lens stock can trace once and edge every job on the same system, instead of keeping a template machine just for glass.
How it works
The scanner captures the frame shape optically in about half a second and centers the lens at the same time, with a live image on its touch screen. You can enter PD and fitting height on the scanner, and it aligns the lens to its axis line. Because it removes the lens’s own power and prism from the image, the optical center lands where the prescription needs it: an error of 3 mm on a 2 D lens already gives 0.6 prism diopters.
The edger then grinds the lens to shape and polishes a bevelled or flat edge. It does not groove or drill, so shops fitting semi-rimless or drill-mount frames add a groover such as the CP-3-800 or a drill such as the CP-24A.
Check before you order
- Lens mix: glass, resin and polycarbonate are listed. Tell us your share of glass, and ask before planning high-index.
- Frame types: bevel covers full-rim frames; add the CP-3-800 for semi-rimless grooves or the CP-24A for drill mounts.
- Lens sizes: 25–80 mm. For very small blanks, check the size against your frames.
- Bench space for two units: 650 × 540 mm for the 65 kg edger and 230 × 370 mm for the scanner, with room for water supply and drainage.
- Power: 550 W for the edger and 60 W for the scanner, ideally on a dedicated circuit with no extension cords.
- Consumables to order with it: blocking pads and suction cups that fit the chuck, plus spare wheels for glass.
Good practice with glass
- Scan the frame and check the traced shape on the scanner screen.
- Enter PD and fitting height, center the lens with the live image and block it.
- Select glass as the lens material, so the edger uses the right wheel and pressure.
- Edge, check the size against the frame before removing the block, and polish if the edge will show.
- Give glass edges a light safety bevel on a hand edger such as the CP-7A-35WV.
- Mount and do a final check against your tolerance standard (ANSI Z80.1 in the US).
Care and maintenance
- Glass swarf is abrasive: change the water more often on days with many glass jobs.
- Rinse the grinding chamber daily and follow the machine manual for service intervals.
- Keep the scanner’s lens table and optics clean; dust shows up in the image.
- Replace dull wheels before they start to chip edges.
Background sources: Edger basics (20/20 Magazine) · Getting an edge-ucation (20/20 Magazine)
Often ordered with the SJG-900
SJG-900 / 900A questions
Can the SJG-900 edge glass lenses?
The SJG-900 does: glass, resin and polycarbonate are listed. The SJG-900A does not edge glass; it is for resin, high-index and PC. Tell us your lens mix and we confirm the wheel configuration on the quotation.
SJG-900 or SJG-900A?
If you edge glass, even occasionally, choose the SJG-900. The SJG-900A does not edge glass; it is for resin, high-index and PC, and adds a second bevel position (two selectable, fixed for thin and thick lenses) and an electronic level.
Can I enter PD and fitting height?
Yes. Both are entered directly on the scanner’s touch screen, and the lens is aligned to its axis line automatically.
Does it groove semi-rimless lenses?
No. It bevels and polishes. For nylon-cord frames add the CP-3-800 groover, or choose the SJG-1000AK, which grooves on the edger.
SJG-900 or SJG-1000AK?
Both are patternless systems with a separate scanner. Choose the SJG-900 if you edge glass; choose the SJG-1000AK if you fit semi-rimless frames often and want grooving on the edger.
SJG-900 or AE-688?
Both edge glass. The AE-688 edges to a template held in a clamp; the SJG-900 traces the frame optically, centers the lens on a live image and needs no pattern.