Notching glass and mirror
September 8, 2008
Cutting notches in glass involves drilling and cutting, and is used frequently in mirror work on corners, steps or existing wall fixtures.
Cutouts made by notching include the corner cutout, outlet cutout, peninsula notch, and the island or center cutout. Procedures for the peninsula notch and island or center cutout follow.
When notching, make sure there are always two sides of the notch that are separated from the glass. This will allow the notch cutout to be released without binding the glass and damaging the edges.
A peninsula notch is a U-shaped notch cut from the edge of glass or mirror used to accommodate fixtures in walls or for pass-throughs. The following procedure uses a glass notching saw to make the cuts. This fabrication is more difficult than cutting wall outlets and requires careful attention to detail and workmanship. The depth and width of the notch determines the procedure to be used.
The procedure for cutting a 2-inch-by-4-inch peninsula notch follows:
1. Carefully lay out the notch on the glass or mirror.
2. Put on your eye protection.
3. Drill two holes at the intersections.
4. Using a glass notching saw, saw from the edges into each hole.
5. Score a line from hole to hole across the 4-inch dimension.
6. Break out the rectangular cutout piece.
7. Seam the edges with a narrow belt sander or drum sander, or by hand
8. Seal the edges if fabricating mirror.
An island cutout is an inside cutout not located at the edges of the glass or mirror surface and used to accommodate a heat register, light fixture or thermostat. It is difficult to fabricate and requires skill and close attention to detail.
The size of the cutout determines how it should be made. One approach uses the glass notching saw and offset running pliers. Be sure to mark the cut line with masking tape before using the glass notching saw.
The procedure for island cutout follows:
1. Carefully lay out the pattern.
2. Put on your eye protection.
3. With a glass drilling machine, drill holes within the intersecting lines of the pattern.
4. Score lines from the center of each hole to the centers of the others.
5. Run these cuts with the offset running pliers.
6. Mark a diagonal line with masking tape from one hole to the opposite hole. Cut along this line with a glass notching saw.
7. Remove the two triangular segments by reversing the thrust of the offset pliers so that the breaking pressure is upward.
8. Score lines along the edges of each hole along the outside of the cutout.
9. Break out the strips with the offset pliers.
10. Seam the edges.
11. Seal the edges, if fabricating mirror.
When notching glass and mirror, make sure you have the following tools and supplies on hand: a glass notching saw; a glass drilling machine; offset running pliers; cut running pliers; a narrow belt sander or drum sander; a hand glass cutter; and coolant, water, grit or turpentine.
Remember to always wear safety glasses when using power tools on glass. Let the tool do the work. With a glass notching saw, let the blade cut the glass. Do not try to force the cut or it will bind the blade, causing glass damage. Never cut dry with glass saws; always use water and grit, coolant, or turpentine.
Following are some examples of tools available from industry suppliers.
Bohle cordless wet drilling machine
Bohle America, the Charlotte, N.C., subsidiary of Germany's Bohle AG, offers a high-performance cordless wet drilling machine for hole diameters of 5 millimeters to 70 mm, about 0.2 inch to 2.75 inches. The machine operates on 18-volt rechargeable batteries; no safety switch or insulating transformer is required. It also features integrated water cooling, resulting in shorter drilling times and a longer service life for drill bits, according to a company release. Bohle offers a comprehensive range of accessories for the cordless wet drilling machine, which can operate at speeds of 450 rpm, 1,450 rpm or 2,000 rpm. The Profi model with vacuum suction holder is equipped to drain off the drilling dust and coolant, keeping the entire drilling area clean.
For the supply of the coolant circulation, Bohle offers a 3-gallon pressurized water tank.
704/887-3457 | www.bohleamerica.com
Starlite diamond core drills
The Starlite metal-bond diamond core drill has diamonds that are held in a metal matrix bond for core drilling glass. It has a high concentration of diamond per cubic inch of drill, making it a long-lasting fast tool, according to representatives from Starlite Industries, Rosemont, Pa. In addition, the core drill requires minimal pressure, resulting in less entrance-hole chipping.
800/727-1022 | www.starliteindustries.com
Diamond Tech glass saws
The DL5000 saw provides precision cutting with a 61.5-inch diamond-coated steel blade. It features a 15-inch-by-13-inch work surface and a block-and-bearing guide system that adjusts to the thickness of the material being cut, according to representatives from Diamond Tech International, Tampa, Fla. The portable saw weighs 55 pounds and has its own carrying handle, in addition to a variable-speed motor that enables users to cut through glass, granite and anything in between. The saw is available with an instructional manual, toll-free tech support line and a 1-year warranty.
800/937-9593 | www.diamondsaws.com
Glass Supplies cutting fluids
Glass Supplies Inc., a Charlotte, N.C.-based import distributor, offers a range of fully evaporating glass cutting fluids specifically formulated for cutting all types of soft-coated glass. The fluids evaporate specifically with regards to the type of glass processed and can be customized for unique applications, according to company press material. Other available products include synthetic grinding coolants, polishing compounds, glass cleaners and glass markers.
704/588-7524 | www.glasssupplies.com