by Bob Beranek

A few months ago at Auto Glass University in Michigan I had a conversation with one of my students regarding cutting auto glass versus buying it pre-cut. I think it’s becoming a lost art. Cutting laminated glass is a challenge not many professionals pursue since most parts can be purchased pre-cut. However, cutting your own laminated parts can put a few more dollars in your pocket if you have the equipment and time.

In the past I’ve written about some of the techniques used to cut laminated glass and I urge you to look back for more information if you’re interested. Nevertheless, I have not examined the most important tool in glass fabrication, the glass cutter itself. There is more to a glass cutter than you might think.

There is an assortment of glass cutters that each have characteristics that appeal to the glass fabricator. You can choose between:

  • The type of handle;
  • The type of head;
  • The cutting wheel composition;
  • The wheel hone angle; and
  • Self-oiling.

Type of Handle

Pencil Grip – Photo Courtesy Home Depot

Pistol Grip – Photo Courtesy Delphi Glass

There are two types of handles: pencil grip and pistol grip. The pencil grip requires about 2-5 lbs. of finger pressure, while the pistol grip requires the same amount of pressure but requires more hand pressure versus finger pressure. The type of grip depends on the cutter’s preference.

Type of Head

Pattern Cutting – Photo Courtesy

Straight Cutting – Photo Courtesy Equalizer

There are two types of cutting heads: straight cutting and pattern cutting. The pattern cutting head is narrower and swivels 360 degrees. Meanwhile, the straight cutting head is wider and does not pivot. Though auto glass technicians cut from patterns, most cuts are straight, making the straight cut head preferred.

Cutting Wheel Composition

Most glass cutting wheels are made of steel because it’s the most economical, but they dull faster. The tungsten carbide wheel is another option. If you plan on cutting a large amount, the tungsten carbide wheel is the head of choice.

Wheel Hone Angle

The hone angle for most cutters ranges between 120 degrees – 154 degrees, the higher the number the sharper the wheel. A cutter with a 154 degree hone angle is recommended for glass over ½-inch thick. Auto glass cutters never cut glass this thick, so the lower hone angles are recommended.

Self-oiling Cutters

Oil’s purpose in glass cutting is to lubricate the cutting wheel for smooth scores. Some cutters have a reservoir built into the handle for oil to be dispensed. These are exceptional cutters, but if dry cutters are stored in oil, a less expensive cutter can be used with excellent results.

Photo Courtesy

Photo Courtesy Equalizer

Glass cutters are rarely sharpened, using it hones it and keeps it in “round.” The end of a glass cutter is when the wheel goes out of its “round” shape. If a glass cutter is dropped on the floor it, or at least the head must be replaced. A burr in the wheel will cause the cutter to skip and cause the glass to erratically break.

Consider adding glass fabrication to your area of expertise. With a little practice, it can bring big dividends.

Comments (5)

  1. […] BLOG: Choosing a Glass Cutter […]

  2. Jeff Cothery said on 06-09-2018

    The oil is actually there to soak into the scored cut and prevents it from self healing. If a score is made dry and not broken or snapped quickly it will actually become harder to break. Good idea teaching auto glass guys to cut lami!

  3. frisco slim said on 17-05-2020

    The text says that the higher the number of the hone angle, the sharper the wheel will be. But the diagram shows the opposite, that the larger value “V” is, the blunter the edge of the wheel will be. Could you clarify?

    • James said on 12-01-2021

      The angle measured is that between the two facets of the wheel edge. A 120 to 140 degree angle is (relatively) sharp as glass cutters go, and is suited to light pressure (as little as 5 or 6 pounds) to score thin glass, making a score line (“fissure”) 0.002 inches wide (2/1000). A 154 or 160 degree angle is (relatively) more blunt, used with greater pressure (25 pounds +/-) to score thicker glass, producing a score line (“fissure”) 0.006 (6/1000) inch wide. 25 pounds of pressure would possibly break thin glass; light pressure on a (relatively) narrow cutter wheel (120 to 140 degrees) may not produce a wide enough fissure to successfully break thicker glass.
      Wheel angle and pressure must be matched, appropriate to glass thickness. The larger “footprint” of a more blunt (broad) wheel works with greater pressure (on thick glass); the smaller “footprint” of a more narrow wheel works with lighter pressure on thin glass.

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