An introduction to the cutting of glass and its edges

Practice is necessary for scoring and breaking out the cut glass during the glass-cutting process. To score and break out a cut piece with precise cut edges and a smooth surface devoid of nicks, bites, or chips, glass cutting is required.

Glass is not cut by a glass-cutting tool the same way as it is by scissors, a saw, or a router. Glass is cut using a force-generated cutting technique that involves moving a cutting wheel across a sheet of glass. The wheel produces tiny fractures that are the right breadth and size to achieve a flawless breakout.

1. The Glass Cutting Process

1.1 Fissure

The surface of the glass is broken as the cutting wheel passes over it, causing a fissure. The almost invisible fracture could not even be apparent after rolling the wheel over the glass. The continuous ring of reflected light can be observed by gazing into the glass.

The power and speed with which the fissure is sliced are important variables. The necessary amount of force to form the fissure without breaking the glass surface is considered the amount of force. The force has been used up if the score turns into a white rough line. Glass that has developed lateral cracks may result in a poor break or one that differs from the score. To make the proper fissure and prevent crushing the glass, the application of force must be consistent along the whole length of the score. Different fissure depths are caused by variations in force, which will hinder the breakout.

1.2 Cutting Area

The sort of work surface used in cutting glass is important and must be chosen with care. In cutting performed by professionals, ideal surfaces will have previously been created and tailored for cutting. The best cutting surfaces are flat, hard, and devoid of any kind of dirt, chips, or other blemishes. It must be pliable, strong, long-lasting, and able to sustain the cutting force required. The thickness of the cover material applied to the cutting surface should not exceed 0.0625 inches or 0.16 centimeters. The cutting process will be hampered by a thicker surface. It is advised to use a grid-cutting surface, as shown below. Slivers and pieces of the glass that are sliced fall into the grid cells.

1.3 Cutting

The glass surface needs to be cleared and cleaned along the cut line before cutting. To create a suitable fissure, the glass cutting tool's wheel needs to be able to roll freely, uniformly, and smoothly as it comes into contact with the glass. The fissure becomes weaker if there are any obstructions or pieces in the wheel's path.

Glass is frequently protected during shipping by a powder coating. This needs to be taken out before you start cutting. The protective powder can be removed by using any kind of cleanser to clean along the cut's edge. Only one score should be made in the fissure. The glass may break and crack if it is scored repeatedly. It must be kept in mind that cutting glass is a delicate process that requires the utmost caution.

1.4 Wheel Cutter Angle

It is impossible to pinpoint the precise cutter wheel angle for a cutting job due to the infinite variety of cutter wheel angles. Most cutters have an angle between 120° and 124°; this is suitable for glass with thicknesses of 0.16 cm to 0.236 cm and ranges from 0.063 to 0.093 in. Friction between the cutter and the glass, which develops as the glass relaxes after the cutter passes, is what causes flaking. Using a cutter with an oil reservoir or lubricating the score line will help you prevent this problem, which is typical with any angled cutter. Flaking should be avoided because it alters the fissure's properties and can result in chips during escape.

1.5 Breakout

It's crucial to use a roundhead copper or polyurethane tapper to carry the score through the crack before starting the breakout. If the score is very clean, this technique will occasionally result in a breakout. Blows should be tapped directly beneath the score.

Where the score stopped should be where the breakout begins. An anvil and cut running pliers can be utilized for greater breakout control. To prevent excessive bending, which can lead to chipping, the breakout needs to be done slowly and cautiously. Regardless of the technique employed, keeping the shortest angle is the most crucial aspect of the breakout. To separate the sheet's edge into small strips, use nipping pliers. Cut running pliers have jaws that are specifically made to start the breakout at a sheet's edge. With grozing pliers, corners, and edges are nibbled and shaped.

2. Glass Cutting Edges

Different edge treatments are used when cutting glass, which has an impact on how well the end product works. Edging has several benefits, including increased functionality, safety, aesthetic appeal, dimensional tolerance, and resistance to chipping and cracking. Some examples of edges include:

2.1 Seamed

Safety seams and swiped edges are other names for seams that are sewn. To make the finished piece safe for handling, the jagged edges of the glass are lightly sanded off with a sanding belt. The method is employed in applications where the edge won't be visible and doesn't result in a decorative or completed edge.

2.2 Beveled

An edge is smoothed during the beveling, chamfering, or grinding processes by being run down a belt to remove any chips and deformities. The procedure produces a straight or curved smooth chamfer top and bottom. Bevels are available in a range of lengths between 0.5 inches (00.127 cm) and 1.5 inches (3.8 cm).

2.3 Crayon Grind

For a frosty, satin, or matte glass surface, a pencil grind edge is slightly rounded. The term "pencil" refers to the radius of the edge, which resembles the C-shape of a pencil.

2.4 Smooth Polish

The edges are flat polished after being cut, giving them a sleek appearance and shining finish. The technique includes chamfering at a 45° angle on the top and bottom to reduce sharpness. The edges mentioned above are just a few examples of the various edges that can be used on a piece of glass that has been finished being cut. A selection of some of the additional combinations is shown in the diagram below.

2.5 Machines for cutting glass

The parts of a commercial glass-cutting machine are quite similar to those used in hand glass-cutting equipment and techniques. These include a smooth surface and the workpiece's precise placement. Although automation makes cutting glass simpler and faster, cutting still involves a fragile and sensitive material that is susceptible to fracture or cracking at any point in the process. Laser cutting, a more recent addition to glass-cutting equipment, can both cut and etch shapes into glass. A stronger laser than those used to etch glass is required if the laser is intended to cut through a piece of glass.

2.6 Machines for cutting glass

CNC control systems, servo motors, and drivers are all features of glass-cutting equipment. They have a variety of cutter wheels that can make a variety of cuts. Increased stability, high precision, and a variety of cutting tools are provided by the use of glass cutting machines, which may create cuts that are straight, angled, irregular, and circular.

2.7 Laser Cutting Machine

Flat and curved glass can be cut using laser cutting equipment, which can be programmed using CNC G codes. The incredibly smooth cutting surface of a laser glass-cutting device is a significant advantage. Given that lasers are made to pass through glass, it is unusual for them to be used to cut glass. It is conceivable to configure a laser that can cut through glass using an ultra-short, pulsed laser in the picosecond or femtosecond range. A laser may cut through the glass because of the large spatial and temporal density of the photons in the pulse, which changes the mechanism's rate of absorption for transparent substances.

2.8 Glass Cutting Table

For cutting that is both straight and shaped, a glass cutting table is appropriate. Although it has a compact footprint, this kind of glass-cutting machine can deliver exceptionally accurate and exact cuts. With tolerances of 0.15 mm, a glass cutting table can cut materials with thicknesses ranging from 0.3 cm to 1.9 cm (1/8 in. to 3/4 in.) at a speed of 200 m/min (218 yd/min).

2.9 Cutting Glass with a Water Jet

Typically, water jet glass cutting is used to produce artistic pieces and beautiful motifs. The varieties of glass that can be cut using the water jet technique are restricted because it cannot be used on thin or poor-quality glass but is perfect for thick glass of great quality. The item that needs to be cut must be securely supported, just like with all the other glass-cutting techniques. The object needs to be securely held in place and rest on something soft enough to stop the water jet from bouncing back. Plywood and Styrofoam are two materials that are frequently used.

During the water jet process, an abrasive substance is suspended in pressured water. The success of water jet glass cutting depends on the timing between the water and abrasive material. They must both simultaneously impact the glass's surface. The cutting of glass can be severely impacted by insufficient support, temperature swings, and timing of the abrasive material, which can result in cracking or breaking of the glass.

2.10 Glass Saws

Glass saws are a quick and practical way to cut thick, heavy textured, or fused glass. Hand cutting of heavy, thick glass is practically impossible. Glass-cutting saws with rings, bands, and wires perform the task effectively, rapidly, and precisely. Glass-cutting saws' blades have coated or diamond-tipped tips that enable them to make delicate cuts. Target lights and recirculating water pumps are features of glass cutting saws that indicate the cut's course. Click here for Saw Blade.

2.11 Glass Edging Equipment

The edge of the glass is prepared with a glass edging machine, which grinds and chamfers the edge into various forms so that it can be installed for use as a mirror, window, and other purposes. Glass edging machines can create many edge designs, including curves, angles, bevels, and others. The glass fragment is kept in place as it moves through the machine by a sucker plate.