Buying guide · Glass Double-Edging Machines · Updated August 2026
Glass Double-Edging Machines: The Buying Guide
A double-edging machine, also called a bilateral edger, grinds two opposite edges of a flat pane at the same time. The glass runs between two chain conveyors. Each conveyor carries a row of grinding wheels. One pass finishes two edges. Turn the pane 90 degrees, run it again, and all four edges are done. That is why the double edger is the throughput machine in an edging department, and the single edger is the flexible one.
This guide covers the configurations you will be offered and the figures that decide the purchase. It uses only the machines listed in this category on GlassMachines.net, from Hiseng and Schiatti Angelo S.r.l. Prices are not published here. Request pricing from the manufacturer.
What a double-edging machine does and where it sits on the line
Cut glass has a raw edge. It is sharp, it holds micro cracks, and it will fail in tempering or in service. The double edger removes it. It grinds a controlled amount off both long sides, arrises or polishes the result, and holds the pane to a set width.
The machine sits after cutting and breakout, with the scored edges already snapped off. Most plants put the washer after the edger, because grinding leaves powder and coolant on the sheet.
After the edger the pane goes to drilling, then washing, then tempering, an insulating glass line or a laminating line. A pane that leaves the edger out of square shows that fault at every station after it. Treat the edger as a size-holding machine, not only a finishing machine.
Most plants run two passes. The first takes the long edges, the pane is turned, and the second takes the short edges. The Hiseng SYM Straight Line Double Round Edging Machine builds that into one line: a first round edger, a transfer table and a second round edger under one control system.
Types and configurations
The category looks like one machine, but buyers face four real splits.
The first is flat edge against round edge. A flat-edge bilateral grinds a straight ground or polished edge with a small arris on each face, the standard architectural and furniture finish. A double round edger grinds a rounded profile, which is what appliance, solar and automotive parts usually need.
The second is rough grinding against grind and polish. A rough grinding line takes the sharp edge off fast and leaves a matt finish, which is all an insulating glass unit needs. A polishing line adds fine grinding and polishing wheels, runs slower, and leaves a clear edge for exposed glass.
The third is size class: small parts, large panes and jumbo sheets need different frames. The fourth is wheel count. More spindles per side means more stock removed per pass, but also a longer machine, more power and more wheels to buy.
- Flat edge and arris: the Schiatti Angelo S.r.l. BFP Series grinds polished flat-edge and arris profiles on both sides.
- Round edge: the Hiseng SYM Straight Line Double Round Edging Machine rounds four edges and cuts safety bevels, with a dubbing width of 0 to 4 mm.
- Rough grinding for volume: the Hiseng SZM Automatic Super Speed Double Edger Line grinds up to 25 metres per minute.
- General purpose: the Hiseng HSDN Straight Line Double Edging Machine covers 3 to 25 mm glass in eight size classes.
- Small parts: the Hiseng HSDN Small Glass Double Edging Line takes glass to 130 x 130 mm and combines round grinding, fine grinding and polishing.
- Jumbo: the Hiseng HSDT Jumbo Glass Bilateral Edger Line carries 5, 9, 12 or 15 spindles on each side.
- Low-E film removal: the SZM-10-CM and SZM-18 arrangements add a film removal station.
How it works, step by step
Step one is width setting. The operator enters the finished width and a servo drive moves one side of the machine to it. The other side is fixed. That move matters on short runs, because the machine grinds nothing while it happens. The Hiseng HSDN Straight Line Double Edging Machine changes size at 1 to 12 metres per minute.
Step two is clamping. The pane enters between an upper and a lower belt that hold it flat and drive it forward. Pressure must be firm enough to stop slip and soft enough to leave no marks.
Step three is rough grinding. The first diamond wheels on each side take most of the stock off. Heat and coolant demand are highest here.
Step four is fine grinding. Finer wheels clean up the face and set the final width. The Hiseng HSDN Straight Line Double Edging Machine holds a parallel tolerance of 0.2 mm per metre or better, with grinding motors running under inverter control to 4,200 rpm.
Step five is the arris or chamfer. Small angled wheels break the sharp corners. On the Hiseng SYM Straight Line Double Round Edging Machine the chamfering mechanism is dual servo driven and runs 0 to 20 metres per minute.
Step six is polishing, on machines that have it. Resin wheels bring the ground face up to a clear finish. Polishing is the slowest station, so a polishing line is always slower than a rough grinding line of the same length.
Coolant runs through all of it. Water carries heat and powder away, drains to a tank, settles and is pumped back. Guideways are the weak point, because powder in a guide destroys straightness. Hiseng uses a half dovetail guide for the timing belt, a T shape belt that keeps powder out, and a unity sliding board structure on linear guides to reduce accumulated error.
The figures that decide the purchase
Eight numbers settle most double-edger decisions. Take them from your own order book: largest pane, smallest pane, thickest glass, busiest hour. The table shows the ranges stated in this category. Anything outside them is a special build and must be confirmed in writing.
| Figure | Range stated in this category | Why it decides the purchase |
|---|---|---|
| Maximum glass length | 1,200 to 1,600 mm on BFP mini; up to 4,500 mm on BFP 12, BFP 20 and BFP 35; processing size to 6,000 mm on the HSDN series | Sets the largest pane you can edge in house. |
| Minimum glass size | 100 mm on BFP mini; 160 mm on the larger BFP models; 130 x 130 mm on the HSDN small line; 250 x 250 mm on SYM | Small parts lose grip between the belts. This number kills more orders than the maximum. |
| Thickness range | 2 to 8 mm on BFP mini; 3 to 20 mm on BFP 12 and BFP 20; 3 to 35 mm on BFP 35; 3 to 25 mm on HSDN and SYM | Thick glass needs spindle power and frame mass. |
| Feed speed | 1 to 6 m/min on BFP mini; 0.9 to 4.5 m/min on the larger BFP models; 1 to 10, 1 to 20 or 1 to 30 m/min on HSDN; to 25 m/min on SZM | Feed rate times pane length is your real hourly capacity. |
| Size change speed | 1 to 12 m/min on HSDN; 1 to 10 m/min on SYM | Mixed-size work spends more time changing width than grinding. |
| Accuracy | Parallel tolerance 0.2 mm per metre or better on HSDN; parallel 0.2 mm and diagonal 0.5 mm on SYM | Out of square panes fail later, at the insulating glass line. |
| Spindle or wheel count | 5, 9, 12 or 15 spindles per side on HSDT; 10, 12 or 18 wheel arrangements on SZM; dual grinding heads on BFP 20 | Sets stock removed per pass and the wheel budget. |
| Installed power | 16.7 kW on BFP mini, 26.3 kW on BFP 12, 36 kW on BFP 20, 40 kW on BFP 35; 12 kW, 23 kW or 32 kW across SYM sizes | Sizes the incoming supply and most of the running cost. |
Choosing by what you produce
The product decides the configuration. Start from the finished part and work back.
Insulating glass units. The edge is hidden in the frame, so it needs to be safe and square, not clear. A rough grinding line is the answer. The Hiseng SZM Automatic Super Speed Double Edger Line is built for construction, door and window insulating glass, clear glass and Low-E glass. If you run Low-E, specify the film removal station on the SZM-10-CM or SZM-18.
Tempered glass and shower doors. Every edge is exposed and every edge is a stress raiser, so you need a polished flat edge with a clean arris. The Schiatti Angelo S.r.l. BFP Series covers this, and BFP 35 takes glass to 35 mm. The Hiseng HSDN Straight Line Double Edging Machine covers 3 to 25 mm.
Mirrors, furniture shelves, tables and stairs. Schiatti Angelo S.r.l. names this work for the BFP Series, and BFP 20 uses dual grinding heads for better edge quality at a higher rate.
Appliance glass and small parts. The Hiseng HSDN Small Glass Double Edging Line handles glass to 130 x 130 mm and can be paired with a loading robot and inline corner grinding and drilling.
Solar, furniture, home appliance and automotive glass with rounded edges. The Hiseng SYM Straight Line Double Round Edging Machine finishes four rounded edges and safety bevels in one operation, on glass from 250 x 250 mm up to 2,000 x 1,500 mm.
Jumbo architectural glass. The Hiseng HSDT Jumbo Glass Bilateral Edger Line is an end-edging line for super jumbo work, and its table can be extended later as production grows.
What a quote should include
A double edger is not a boxed product. Two quotes for the same model can differ widely because of what is left out. Ask for a line-item quotation.
Ask the manufacturer these questions. Which wheel set is fitted, and what does a replacement set cost? What parallel and diagonal tolerance is guaranteed, and how is it proven at handover? What is the size change time between two sizes you actually run? Which brand are the servo drives and electrical components? The Hiseng SYM Straight Line Double Round Edging Machine states Siemens servo drives and Schneider Electric components, which makes local spares easier to source.
- Factory-direct machine price, with the exact model and size class named.
- Wheel set fitted at the factory, plus the price of a full replacement set.
- Export crating, fumigated and sea worthy.
- Freight with the Incoterm stated, plus insurance and port charges.
- Installation: how many engineers, how many days, and who pays travel.
- Commissioning: the acceptance test and the tolerance to be proven.
- Training: how many operators, in what language, and whether maintenance is included.
- Spare parts: a priced one-year and two-year recommended list.
- Warranty: length, cover, exclusions and the fault response process.
- Documentation: electrical and pneumatic drawings, and a parts book with part numbers.
- Options priced separately: film removal station, transfer table, loading robot, inline corner grinding and drilling, and the ERP matching system Hiseng offers to link buffer, cutting, loading, unloading and washer into an unmanned line.
Lead times, installation and running costs
Lead time is driven by size class and options. A standard size ships sooner than a jumbo frame or a machine with a film removal station. Sea freight adds weeks. Ask for the ex-works date and the arrival date separately, and put both in the contract.
Prepare the site before the machine leaves the factory. The BFP range runs from 2,650 kg on BFP mini to 5,150 kg on BFP 35. You need a level floor that takes the load, a drain, water, compressed air and a supply sized for the installed load, which reaches 40 kW on BFP 35. Match the conveyor height to the machines on either side, because the BFP range works at 900 mm or 950 mm.
Installation is normally a few days of levelling and alignment, then electrical connection, then commissioning on your own glass.
Running cost has four parts. Power is the largest. Coolant treatment is second, because the tank has to be settled, filtered and topped up and the sludge disposed of. Wheels are third, so ask other users about wheel life. Labour is fourth and falls as automation rises. A pneumatic quick wheel change, as fitted to the Hiseng SYM Straight Line Double Round Edging Machine, cuts downtime.
Mistakes buyers make
All five are avoidable at the quotation stage.
- Buying on maximum size and ignoring minimum size. A machine that takes a 4,500 mm pane may refuse a small part.
- Comparing feed speed instead of finish. A rough grinding line at 25 metres per minute and a polishing line at 4.5 metres per minute are not competing products. Decide the finish first, then compare speed.
- Forgetting size change time. A plant running many sizes a day can lose more time changing width than grinding.
- Undersizing the services. Installed loads here run from 16.7 kW to 40 kW and coolant tanks reach 990 litres. A machine that arrives before the supply is ready sits in its crate.
- Skipping the acceptance test on real glass. Sign off on your own sizes, with the tolerance measured in front of you.
Machines on GlassMachines.net
Six machines are listed here, from two manufacturers, in four groups: general purpose bilaterals, high speed rough grinding, special profiles and jumbo work.
- Hiseng HSDN Straight Line Double Edging Machine: the general purpose bilateral, in eight size classes from a 300 to 1,500 mm processing size up to 550 to 6,000 mm, with double servo transmission.
- Hiseng HSDN Small Glass Double Edging Line: the same family scaled down for home appliance glass and stair glass, taking parts to 130 x 130 mm.
- Hiseng SZM Automatic Super Speed Double Edger Line: the volume machine for insulating glass work, with 10, 12 or 18 wheel arrangements and a lifting transfer table that shortens the gap between panes.
- Hiseng SYM Straight Line Double Round Edging Machine: a three machine line under one PLC, finishing four rounded edges and safety bevels in one operation on glass up to 2,000 x 1,500 mm.
- Hiseng HSDT Jumbo Glass Bilateral Edger Line: an end-edging line for super jumbo glass with 5, 9, 12 or 15 spindles per side and cup wheels with automatic thickness adjustment.
- Schiatti Angelo S.r.l. BFP Series: the Italian flat-edge and arris range, from BFP mini at 2 to 8 mm through BFP 12 and BFP 20 to BFP 35 at 3 to 35 mm.
Specs to compare, in one list
- Maximum glass length
- It fixes the largest pane you can finish in house.
- Minimum glass size
- Small parts lose grip between the belts, so the minimum decides whether a product family can run at all.
- Glass thickness range
- A machine bought one step too light will never make the removal rate on thick glass.
- Feed or grinding speed
- Feed rate times pane length is your real hourly capacity.
- Size change speed
- In a mixed-size plant the width changes eat more of the shift than the grinding does.
- Parallel and diagonal tolerance
- Out of square panes are rejected downstream, long after the edger is paid for.
- Spindles or wheels per side
- It sets stock removed per pass, installed power and the wheel budget.
- Installed power
- It sizes the incoming supply and is the biggest single line in the running cost.
- Services and footprint
- Coolant tank, air demand, weight and work height decide whether the machine fits the line and the floor you have.
Questions buyers ask
What is the difference between a double edger and a single edger?
A single edger grinds one edge at a time and can follow a shape. A double edger grinds two parallel edges at once and holds the pane to a set width. It is much faster on rectangles, which is most architectural work. Many plants run both and send shaped work to the single edger.
How thick a glass can a double edger handle?
It depends on the model. The Schiatti Angelo S.r.l. BFP Series runs from 2 to 8 mm on BFP mini up to 3 to 35 mm on BFP 35. The Hiseng HSDN and SYM ranges are stated at 3 to 25 mm.
Do I need a polishing line or is rough grinding enough?
It depends on whether the edge is seen. An insulating glass unit hides its edge in the frame, so a rough ground edge is enough and a fast line like the Hiseng SZM Automatic Super Speed Double Edger Line fits. Shower doors, shelves, tables and mirrors show the edge, so they need fine grinding and polishing.
What is the smallest pane a double edger can take?
Smaller than most buyers expect, but only on the right machine. The Hiseng HSDN Small Glass Double Edging Line takes glass to 130 x 130 mm. The BFP Series states 100 mm on BFP mini and 160 mm on the larger models. The Hiseng SYM Straight Line Double Round Edging Machine works from 250 x 250 mm, or 100 x 100 mm on special order.
How much power and water does a double edger need?
Installed power runs from 16.7 kW on BFP mini to 40 kW on BFP 35, with 12 kW, 23 kW or 32 kW across the SYM sizes. Coolant tanks run from 320 litres to 990 litres. Air is stated at 60 to 75 Nl/min on BFP and 0.6 to 0.8 MPa on Hiseng.
Can a double edger remove Low-E coating for insulating glass units?
Yes, if you specify it. Coating has to come off the sealing band before the unit is sealed. The SZM-10-CM and SZM-18 arrangements of the Hiseng SZM Automatic Super Speed Double Edger Line include a film removal station. Ask for it at the quotation stage.
