VOLUME 33, NO. 6, JUNE, 1956
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A CONVENIENT GLASS CUTTER FOR TUBING RAY WOODRIFF Montana State College, Bozeman, Montana
GLASS blowing in the chemistry laboratory requires cutting considerable amounts of glass tubing. A file is ordinarily used to make the scratch. The results are often poor; many pieces splinter to leave jagged edges. Most three-cornered files are actually six sided so that a broad scratch is made. A convenient device t o overcome these difficulties can be made from an ordinary pair of long-nosed pliers. To convert them into a glass cutter, the tips are heated and cooled slowly t o remove the temper. One tip is cut off 14 mm. from the end, and split a distance of from 5 to 6 mm. parallel t o the direction the pinchers operate. A hole is drilled perpendicular t o the cut through the tip t o hold the pin for a cutting wheel. The wheel from a regular glass cutter or a, wheel obtained from a chemical supply house is inserted into the hack-saw cut and secured in place by a, pin driven through the hole. A round notch, one mm. deep, is filed a t a, distance of about 6 mm. from the wheel. This is useful for holding
pieces of short tubing. A corresponding notch is filed in the other jaw. I n the jaw opposite the wheel a longitudinal groove is ground out so that the wheel and jaw do not come in contact when the pliers are closed. The tip of this jaw is bent inward to form a shallow V groove opposite the wheel. This hook prevents glass tubing from slipping out of the pliers while in use.
